Pilot study of a decision aid on BRCA1/2 genetic testing among Orthodox Jewish women

INTRODUCTION

Orthodox Jewish women face unique social, cultural, and religious factors that may influence uptake of BRCA1/2 genetic testing. We examined the impact of a web-based decision aid (DA) on BRCA1/2 genetic testing intention/completion among Orthodox Jewish women. We conducted a single-arm pilot study among 50 Orthodox Jewish women who were given access to a web-based DA entitled RealRisks and administered serial surveys at baseline and 1 and 6 months after exposure to the DA. Descriptive statistics were conducted for baseline characteristics and study measures. Comparisons were made to assess changes in study measures over time. Fifty Orthodox Jewish women enrolled in the study with a mean age of 43.9 years (standard deviation [SD] 14.6), 70% Modern Orthodox, 2% with personal history of breast cancer, and 68% and 16% with a family history of breast or ovarian cancer, respectively. At baseline, 27 (54%) participants intended to complete genetic testing. Forty-three participants (86%) completed RealRisks and the 1-month survey and 38 (76%) completed the 6-month survey. There was a significant improvement in BRCA1/2 genetic testing knowledge and decrease in decisional conflict after exposure to the DA. At 1 month, only 20 (46.5%) completed or intended to complete genetic testing (p = 0.473 compared to baseline). While the DA improved genetic testing knowledge and reduced decisional conflict, genetic testing intention/completion did not increase over time. Future interventions should directly address barriers to BRCA1/2 genetic testing uptake and include input from leaders in the Orthodox Jewish community.

CLINICALTRIALS

GOV ID

NCT03624088 (8/7/18).

Understanding Social, Cultural, and Religious Factors Influencing Medical Decision-Making on BRCA1/2 Genetic Testing in the Orthodox Jewish Community

INTRODUCTION

Although the prevalence of a pathogenic variant in the BRCA1 and BRCA2 genes is about 1:400 (0.25%) in the general population, the prevalence is as high as 1:40 (2.5%) among the Ashkenazi Jewish population. Despite cost-effective preventive measures for mutation carriers, Orthodox Jews constitute a cultural and religious group that requires different approaches to BRCA1 and BRCA2 genetic testing relative to other groups. This study analyzed a dialog of key stakeholders and community members to explore factors that influence decision-making about BRCA1 and BRCA2 genetic testing in the New York Orthodox Jewish community.

METHODS

Qualitative research methods, based on Grounded Theory and Narrative Research, were utilized to analyze the narrative data collected from 49 key stakeholders and community members. A content analysis was conducted to identify themes; inter-rater reliability was 71%.

RESULTS

Facilitators of genetic testing were a desire for preventive interventions and education, while barriers to genetic testing included negative emotions, feared impact on family/romantic relationships, cost, and stigma. Views differed on the role of religious leaders and healthcare professionals in medical decision-making. Education, health, and community were discussed as influential factors, and concerns were expressed about disclosure, implementation, and information needs.

CONCLUSION

This study elicited the opinions of Orthodox Jewish women (decision-makers) and key stakeholders (influencers) who play critical roles in the medical decision-making process. The findings have broad implications for engaging community stakeholders within faith-based or culturally distinct groups to ensure better utilization of healthcare services for cancer screening and prevention designed to improve population health.

Randomized adaptive selection trial of cryotherapy, compression therapy, and placebo to prevent taxane-induced peripheral neuropathy in patients with breast cancer

BACKGROUND

Chemotherapy-induced peripheral neuropathy (CIPN) is a common and debilitating adverse effect of taxane therapy. Small non-randomized studies in patients with early-stage breast cancer (ESBC) suggest both cryotherapy and compression therapy may prevent CIPN. It is unknown which is more effective.

METHODS

We conducted a randomized phase IIB adaptive sequential selection trial of cryotherapy vs. compression therapy vs. placebo ("loose" gloves/socks) during taxane chemotherapy. Participants were randomized in triplets. Garments were worn for 90-120 min, beginning 15 min prior and continuing for 15 min following the infusion. The primary goal was to select the best intervention based on a Levin-Robbins-Leu sequential selection procedure. The primary endpoint was a < 5-point decrease in the Functional Assessment of Cancer Therapy Neurotoxicity (FACT-NTX) at 12 weeks. An arm was eliminated if it had four or more fewer successes than the currently leading arm. Secondary endpoints included intervention adherence and patient-reported comfort/satisfaction.

RESULTS

Between April 2019 and April 2021, 63 patients were randomized (cryotherapy (20); compression (22); placebo (21)). Most patients (60.3%) were treated with docetaxel. The stopping criterion was met after the 17th triplet (n = 51) was evaluated; success at 12 weeks occurred in 11 (64.7%) on compression therapy, 7 (41.1%) on cryotherapy, and 7 (41.1%) on placebo. Adherence to the intervention was lowest with cryotherapy (35.0%) compared to compression (72.7%) and placebo (76.2%).

CONCLUSION

Compression therapy was the most effective intervention in this phase IIB selection trial to prevent CIPN and was well tolerated. Compression therapy for the prevention of CIPN should be evaluated in a phase III study.

CLINICAL TRIAL REGISTRATION

ClinicaTrials.gov Identifier: NCT03873272.

Randomized Phase II Trial of Endocrine Therapy With or Without Ribociclib After Progression on Cyclin-Dependent Kinase 4/6 Inhibition in Hormone Receptor-Positive, Human Epidermal Growth Factor Receptor 2-Negative Metastatic Breast Cancer: MAINTAIN Trial

PURPOSE

Cyclin-dependent kinase 4/6 inhibitor (CDK4/6i) with endocrine therapy (ET) improves progression-free survival (PFS) and overall survival (OS) in hormone receptor-positive (HR+), human epidermal growth factor receptor 2-negative (HER2-) metastatic breast cancer (MBC). Although preclinical and clinical data demonstrate a benefit in changing ET and continuing a CDK4/6i at progression, no randomized prospective trials have evaluated this approach.

METHODS

In this investigator-initiated, phase II, double-blind placebo-controlled trial in patients with HR+/HER2- MBC whose cancer progressed during ET and CDK4/6i, participants switched ET (fulvestrant or exemestane) from ET used pre-random assignment and randomly assigned 1:1 to the CDK4/6i ribociclib versus placebo. PFS was the primary end point, defined as time from random assignment to disease progression or death. Assuming a median PFS of 3.8 months with placebo, we had 80% power to detect a hazard ratio (HR) of 0.58 (corresponding to a median PFS of at least 6.5 months with ribociclib) with 120 patients randomly assigned using a one-sided log-rank test and significance level set at 2.5%.

RESULTS

Of the 119 randomly assigned participants, 103 (86.5%) previously received palbociclib and 14 participants received ribociclib (11.7%). There was a statistically significant PFS improvement for patients randomly assigned to switched ET plus ribociclib (median, 5.29 months; 95% CI, 3.02 to 8.12 months) versus switched ET plus placebo (median, 2.76 months; 95% CI, 2.66 to 3.25 months) HR, 0.57 (95% CI, 0.39 to 0.85); P = .006. At 6 and 12 months, the PFS rate was 41.2% and 24.6% with ribociclib, respectively, compared with 23.9% and 7.4% with placebo.

CONCLUSION

In this randomized trial, there was a significant PFS benefit for patients with HR+/HER2- MBC who switched ET and received ribociclib compared with placebo after previous CDK4/6i and different ET.

Abstract PD11-01: PD11-01 Evaluation of the PD-1 Inhibitor Cemiplimab in early-stage, high-risk HER2-negative breast cancer: Results from the neoadjuvant I-SPY 2 TRIAL

Background: I-SPY2 is a multicenter, phase 2 trial using response-adaptive randomization within biomarker subtypes defined by hormone-receptor (HR), HER2, and MammaPrint (MP) status to evaluate novel agents as neoadjuvant therapy for high-risk breast cancer. The primary endpoint is pathologic complete response (pCR). Cemiplimab (Cemi) is a PD-1 inhibitor approved for the treatment of NSCLC, cutaneous basal, and squamous cell cancer. Here, we report current efficacy rates of Cemi in combination with paclitaxel followed by AC.

Methods: Women with tumors ≥ 2.5cm were eligible for screening. Only HER2 negative (HER2-) patients were eligible for this treatment; HR positive (HR+) patients had to be MP high risk. Treatment included paclitaxel 80 mg/m2 IV weekly x 12 and Cemi 350 mg IV given q3weeks x 4, followed by doxorubicin/cyclophosphamide (AC) every 2 weeks x 4. The control arm was weekly paclitaxel x 12 followed by AC every 2-3 weeks x 4. All patients undergo serial MRI imaging; and imaging response (at 3 weeks, 12 weeks and prior to surgery) were used along with accumulating pCR data to continuously update and estimate pCR rates for trial arms. Analysis was modified intent to treat. Patients who switched to non-protocol therapy count as non-pCR. The goal is to identify (graduate) regimens with ≥85% Bayesian predictive probability of success (i.e. demonstrating superiority to control) in a future 300-patient phase 3 neoadjuvant trial with a pCR endpoint within responsive signatures. Cemi was eligible to graduate in 3 pre-defined signatures: HER2-, HR-HER2-, and HR+HER2-. To adapt to changing standard of care, we constructed “dynamic controls” comprising ‘best’ alternative therapies using I-SPY 2 and external data and estimated the probability of Cemi being superior to the dynamic control.

Results: 60 HER2- patients (28 HR+ and 32 HR-) received Cemi arm treatment. The control group included 357 patients with HER2- tumors (201 HR+ and 156 HR-) enrolled since March 2010. Cemi graduated in HR-/HER2- signature. Estimated pCR rates (as of June 2022) are summarized in the table.

Immune-related endocrine disorders include: hypothyroid (14.5%), adrenal insufficiency (10%), hyperthyroid (4.8%),) and thyroiditis (3.2%). Only one grade 3 adrenal insufficiency was observed. All immune related AE’s were manageable. Additional biomarker analyses are ongoing and will be presented at the meeting. Response predictive subtypes (Immune+ vs Immune-) and additional predictive biomarkers were assessed. Associations with pCR will be presented at SABCS.

Conclusion: The I-SPY 2 study aims to assess the probability that investigational regimens will be successful in a phase 3 neoadjuvant trial. Anti-PD-1 therapy with Cemi resulted in a higher predicted pCR rate in HR-/HER2- 55 rate% disease compared to control at 29%. Immune-mediated AE’s were observed. This data is consistent with previously published data using check point inhibitors in early-stage HR-/HER2- breast cancer.

Estimated pCR rates

Citation Format: Erica Stringer-Reasor, Rebecca A. Shatsky, Jo Chien, Anne Wallace, Judy C. Boughey, Kathy S. Albain, Hyo S. Han, Rita Nanda, Claudine Isaacs, Kevin Kalinsky, Zahi Mitri, Amy S. Clark, Christos Vaklavas, Alexandra Thomas, Meghna S. Trivedi, Janice Lu, Smita Asare, Ruixiao Lu, Maria Pitsouni, Amy Wilson, Jane Perlmutter, Hope Rugo, Richard Schwab, W. Fraser Symmans, Nola M. Hylton, Laura Van ’t Veer, Douglas Yee, Angela DeMichele, Donald Berry, Laura J. Esserman, I-SPY Investigators. PD11-01 Evaluation of the PD-1 Inhibitor Cemiplimab in early-stage, high-risk HER2-negative breast cancer: Results from the neoadjuvant I-SPY 2 TRIAL [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr PD11-01.

Abstract P3-07-22: Presurgical Trial of Metformin plus Atorvastatin in Women with Operable Breast Cancer

Introduction:

Metformin is an oral anti-diabetic agent that exhibits direct anti-proliferative effects on pre-clinical models through activation of the AMPK pathway. However, pre-surgical studies of metformin alone among women with operable breast cancer have not consistently shown reductions in tumor proliferation, and adjuvant metformin in women with high-risk operable breast cancer did not improve invasive disease-free survival compared with placebo. Dysregulation of the mevalonate pathway of cholesterol synthesis can also lead to cell proliferation, and inhibition of HMG-CoA reductase by statins can decrease tumor proliferation. There is close interaction between the AMPK and mevalonate pathways, and dual therapy with a statin and metformin might be synergistic to decrease cell proliferation. We evaluated the effect of combination therapy with metformin plus atorvastatin on markers of proliferation (i.e. Ki67 proliferation index) in women with operable breast cancer.

Methods:

We conducted an open-label, single-arm presurgical “window of opportunity” study of metformin plus atorvastatin in non-diabetic women age 21+ years with newly-diagnosed stage 0-III operable breast cancer at Columbia University Irving Medical Center (CUIMC). Enrolled patients received metformin 1500mg oral [p.o.] daily (500mg in the morning/1000mg in the afternoon) and atorvastatin 80mg p.o. nightly for up to 4 weeks before breast surgery. The primary endpoint was change in Ki67 proliferation index from baseline (diagnostic biopsy) to post-treatment (surgical specimen). Secondary endpoints included change in body mass index (BMI), waist and hip circumferences, tumor assessment of AMPK/mTOR signaling and apoptosis, and reduction of fasting markers of the insulin growth factor pathway. Paired t-tests were conducted to assess difference in ln(Ki67) pre- and post-therapy, as well as differences in absolute Ki67, BMI, and waist/hip circumferences pre- and post-therapy, at a level of significance of 0.05.

Results:

Between Nov. 2013 and Jan. 2018, 22 women were enrolled, and two withdrew consent prior to study treatment. Among evaluable participants (n=20), 45% were Hispanic with median age 56 years (range, 33-73) and median baseline BMI 28.4 kg/m2 (range, 22.5-45.8). All had hormone receptor-positive (HR+), HER2-negative breast cancer, and 16 (80%) had invasive cancer. Median time on study treatment was 11 days (range, 5-29). Changes in Ki67 and anthropomorphic measures are shown in Table 1. There was no significant change in BMI, waist or hip circumference with study treatment. Among women with available Ki67 measurements (n=11), there was no significant difference in pre- and post-treatment ln(Ki67) (p=0.25). There was a numeric decrease in absolute Ki67, though statistical significance was not reached (p=0.09).

Discussion:

There was a numeric reduction in absolute Ki-67 with presurgical metformin plus atorvastatin in patients with newly diagnosed HR+/HER2- breast cancer, although our analysis was limited by small sample size and statistical significance was not achieved. There was no difference in ln(Ki67) or anthropometric measurements. Analyses of additional tissue and serum biomarkers, including markers of insulin resistance, are ongoing to identify associations with absolute Ki67

Table 1

Citation Format: Julia E. McGuinness, Katherine D. Crew, Meghna S. Trivedi, Melissa K. Accordino, Shing M. Lee, Hua Guo, Hanina Hibshoosh, Dawn Hershman, Kevin Kalinsky. Presurgical Trial of Metformin plus Atorvastatin in Women with Operable Breast Cancer [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr P3-07-22.

Abstract P4-01-16: High levels of RSK2 in breast cancer patients is associated with longer PFS in patients treated with PMD-026, a first in class RSK inhibitor

Background: Breast cancer (BC) is the most common malignancy in women and metastatic triple negative breast cancer (mTNBC) remains one of the most difficult to treat cancers with few targeted treatment options. RSK is recognized as a critical signaling component in the MAPK/PDK-1 pathways, is an important driver for BC and a signature of poor prognosis. PMD-026 is the first RSK inhibitor to enter clinical trials and is being developed alongside an immunohistochemistry (IHC) companion diagnostic to select patients with increased activated RSK2 in tumor tissue. A Phase 1/1b trial of PMD-026 in patients with metastatic breast cancer (mBC) or metastatic triple negative breast cancer (mTNBC) established safety at a dose of 200 mg Q12h. Efficacy signals in patients with heavily pretreated mBC/mTNBC are explored in this analysis along with evaluation of the effect of food (FE) on systemic exposure to treatment. Methods: PMD-026 was administered to 41 patients as a single agent in this phase 1/1b open-label study, with 30 patients evaluable for efficacy. Exploratory objectives were to identify subgroups of patients who may optimally benefit from PMD-026. Subgroup analysis of patients included 1) comparing BC patients who received ≤5 vs &gt;5 prior therapies; 2) comparing TNBC patients (de novo vs secondary subtypes)1, and 3) comparing patients with low RSK2 H-scores (&lt; 180) vs high (≥180). In addition, PMD 026 PK was evaluated at the 200 mg Q12h dose and a FE sub-study enrolled 12 patients administered a single 200 mg dose. Results: PMD-026 monotherapy was generally well-tolerated in the 41 mBC patients who were enrolled and treated. Kaplan-Meier PFS analysis of 30 evaluable BC patients who were dosed with PMD-026 showed that patients with less prior therapy (≤5) did significantly better (HR, 0.19; 95% CI [0.06–0.52], p=0.0014) than those with &gt; 5 prior therapies. Subgroup analysis of PFS in those with TNBC demonstrated that de novo TNBC (n=17) had longer time on treatment with PMD-026 compared with secondary TNBC (n=9) (HR, 0.31; 95% CI [0.10-0.99], p=0.0476). In those with de novo TNBC with ≤5 prior therapies, a high RSK2 H-score was associated with significantly longer PFS at the RP2D (4.2 vs 1.3 months, HR, 0.17; 95% CI [0.03-0.80], p=0.0254) than patients with a low RSK2 H-score. In patients with CDK4/6 resistant HR+ BC (n=3), PFS was 5.2 (RSK2 high) vs 1.3 months (RSK2 low). Stable disease was observed in 53% (9/17) of patients with de novo TNBC and in 67% (6/9) of de novo TNBC patients with high RSK2. Tumor necrosis or target lesion reduction (&lt; 30%) was observed in 17% of patients (5/30), all of whom had high RSK2 expression. In the FE sub-study, increased interpatient variability in PMD-026 Cmax and Tmax but not AUC, was observed when administered with food, favored dosing in a fasted state, which is consistent with the pH dependent solubility of PMD-026. Notably, all FE patients (12/12) achieved the target concentration of 1µM (IC90 in preclinical studies) within 4 hours when PMD-026 was taken without food. At the RP2D, PMD-026 taken without food showed relatively consistent exposure among patients over 24 hr timeframe. Conclusions: These findings demonstrate that in patients treated with PMD-026 who had received &lt; 5 prior treatment regimens, had de novo TNBC or CDK4/6 refractory HR+ disease and had high RSK2 scores had longer PFS. Overall, PMD-026 is a well-tolerated, orally available RSK2 inhibitor that will be evaluated further for efficacy in TNBC and CDK4/6i refractory HR+ mBC, in a trial that will prospectively enroll patients based on RSK2 activation as defined by the RSK2 IHC H-scores. Clinical trial information: NCT04115306. 1 Patients diagnosed and treated for TNBC from their initial diagnosis (de novo TNBC) vs patients previously treated for hormone receptor positive (HR+) or human epidermal growth factor 2 receptor positive (HER2+) BC, but became HR or HER2 negative (secondary TNBC)

Citation Format: Judy S. Wang, Muralidhar Beeram, Pavani Chalasani, Lida Mina, Rebecca A. Shatsky, Sara Hurvitz, Meghna S. Trivedi, Robert Wesolowski, Hyo S. Han, Amita Patnaik, Shakeela Bahadur, My-my Huynh, Aarthi Jayanthan, Gerrit Los, Sandra E. Dunn, Andrew Dorr. High levels of RSK2 in breast cancer patients is associated with longer PFS in patients treated with PMD-026, a first in class RSK inhibitor [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr P4-01-16.

Abstract GS5-03: Evaluation of anti-PD-1 Cemiplimab plus anti-LAG-3 REGN3767 in early-stage, high-risk HER2-negative breast cancer: Results from the neoadjuvant I-SPY 2 TRIAL

Background: I-SPY2 is a multicenter, phase 2 trial using response-adaptive randomization within biomarker subtypes defined by hormone-receptor (HR), HER2, and MammaPrint (MP) status to evaluate novel agents as neoadjuvant therapy for high-risk breast cancer. The primary endpoint is pathologic complete response (pCR). Cemiplimab is an anti-PD-1 inhibitor approved for the treatment of NSCLC and cutaneous basal and squamous cell CA. Lymphocyte activation gene 3 (LAG-3) binds MHC class II leading to inhibition of T-cell proliferation and activation and is often co-expressed with PD-1. REGN3767 is a fully humanized mAb that binds to LAG-3 and blocks inhibitory T-cell signaling. Concurrent blockade of LAG-3 with an anti-PD-1 may enhance efficacy of an anti-PD-1.

Methods: Women with tumors ≥ 2.5cm were eligible for screening. Only HER2 negative (HER2-) patients were eligible for this treatment; HR positive (HR+) patients had to be MP high risk. Treatment included Paclitaxel 80 mg/m2 IV weekly x 12 and Cemiplimab 350 mg and REGN3767 1600 mg both given q3weeks x 4, followed by doxorubicin/cyclophosphamide (AC) every 2 weeks x 4. The control arm was weekly paclitaxel x 12 followed by AC every 2-3 weeks x 4. Cemiplimab/REGN3767 was eligible to graduate in 3 of 10 pre-defined signatures: HER2-, HR-HER2-, and HR+HER2-. The statistical methods for evaluating I-SPY 2 agents has been previously described. To adapt to changing standard of care, we constructed “dynamic controls” comprising ‘best’ alternative therapies using I-SPY 2 and external data and estimated the probability of Cemiplimab/REGN3767 being superior to the dynamic control. Response predictive subtypes (Immune+ vs Immune-) were assessed using pre-treatment gene expression data and the ImPrint signature.

Results: 73 HER2- patients (40 HR+ and 33 HR-) received Cemiplimab/REGN3767 treatment. The control group included [357 patients with HER2- tumors (201 HR+ and 156 HR-) enrolled since March 2010. Cemiplimab/REGN3767 graduated in both HR-/HER2- and HR+/HER2- groups; estimated pCR rates (as of June 2022) are summarized in the table. Safety events of note for Cemiplimab/REGN3767 include hypothyroidism 30.8%, adrenal insufficiency (AI) 19.2%, hyperthyroidism 14.1%, pneumonitis 1.3%, and hepatitis 3.8%. All were G1/2 except for 6 (7.7%) G3 AI and 3 (3.8%) G3 colitis. Rash occurred in 62.8%, 9% G3 and 2 pts (2.6%) had pulmonary embolism. X% of adrenal insufficiency cases required replacement therapy. 40 patients (11 HR+ and 29 HR-) in Cemiplimab/REGN3767 were predicted Immune+; 32 (29 HR+ and 3 HR-) were predicted Immune-. In the HR+ group pCR was achieved in 10/11 (91%) patients with Immune+ subtype compared with 8/29 (28%) with Immune- subtype. Additional biomarker analyses are ongoing and will be presented at the meeting.

Conclusion: The I-SPY 2 study aims to assess the probability that investigational regimens will be successful in a phase 3 neoadjuvant trial. Dual immune blockade with a LAG-3 inhibitor and anti-PD1 therapy resulted in a high predicted pCR rate both in HR-/HER2- (60%) and HR+/HER2- (37%) disease. The novel Imprint signature identified a group of HR+ patients most likely to benefit from this active regimen.

Table 1: Estimated pCR rates

Citation Format: Claudine Isaacs, Rita Nanda, Jo Chien, Meghna S. Trivedi, Erica Stringer-Reasor, Christos Vaklavas, Judy C. Boughey, Amy Sanford, Anne Wallace, Amy S. Clark, Alexandra Thomas, Kathy S. Albain, Laura C. Kennedy, Tara B. Sanft, Kevin Kalinsky, Hyo S. Han, Nicole Williams, Mili Arora, Anthony Elias, Carla Falkson, Smita Asare, Ruixiao Lu, Maria Pitsouni, Amy Wilson, Jane Perlmutter, Hope Rugo, Richard Schwab, W. Fraser Symmans, Nola M. Hylton, Laura Van’t Veer, Douglas Yee, Angela DeMichele, Donald Berry, Laura J. Esserman, I-SPY Investigators. Evaluation of anti-PD-1 Cemiplimab plus anti-LAG-3 REGN3767 in early-stage, high-risk HER2-negative breast cancer: Results from the neoadjuvant I-SPY 2 TRIAL [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr GS5-03.

Abstract PD8-06: Incidence of Acute and Persistent Clinically Meaningful Chemotherapy Induced Peripheral Neuropathy in Patients with Early-Stage Breast Cancer Receiving Taxane Therapy: SWOG S1714 (NCT# 03939481)

Background: Taxanes play an important role in the treatment of early-stage breast cancer. Chemotherapy induced peripheral neuropathy (CIPN) is a complication of taxane therapy and can lead to treatment dose reduction or discontinuation, which may ultimately affect overall survival, and can substantially impact quality of life and functional status in survivors. The trajectory of CIPN symptoms is not well described. Methods: SWOG S1714 enrolled participants 18 years or older with Stage I-III primary non-small cell lung, primary breast, or primary ovarian/fallopian tube/peritoneal cancer starting treatment with a taxane-based regimen. Participants with baseline neuropathy were eligible to enroll. Neuropathy was assessed with the patient-reported European Organization for Research and Treatment of Cancer QLQ-CIPN20 (CIPN-20). The occurrence of clinically meaningful sensory neuropathy was defined as an increase of 8 or more points (on a 0-100 scale, with a higher score indicating more severe symptoms) between baseline and follow-up in the sensory neuropathy subscale of the CIPN-20. Assessments occurred at baseline and at 4, 8, and 12 weeks +/- 14 days and 24, 52, 104, and 156 weeks +/- 28 days after registration. Results: Among N=1336 enrolled participants, 1321 were eligible (99%). Of the eligible participants, we will report on the 1198 (90.7%) with breast cancer. The median age was 55 years (range 23-84) and 99.3% were female. The breast cancer cohort included 72.2% White, 11.7% Black, 4.9% Asian, and 11.0% Hispanic/Latino participants. Paclitaxel (every week for 12 weeks or every 2 weeks for 8 weeks) was administered to 56.2% and docetaxel (every 3 weeks for 12-18 weeks) to 43.8%. The mean baseline patient-reported CIPN-20 sensory neuropathy subscale score was 6.2 (standard deviation 12.0). Through one full year of follow up, 1084 participants (90.5%) were evaluable for sensory neuropathy at any time point. At individual assessment times, clinically meaningful sensory neuropathy was reported by 18.7% of participants at week 4, 33.0% at week 8, 46.3% at week 12, 44.8% at week 24, and 47.4% at week 52. Clinically meaningful sensory neuropathy at one or more assessments was reported by 67.8% of participants. Conclusions: In this large prospective cohort of racially/ethnically diverse participants with breast cancer receiving taxane-based therapy, 2 out of every 3 experienced clinically meaningful sensory neuropathy symptoms during the first year of treatment and nearly 50% continue to experience clinically meaningful sensory neuropathy symptoms at the end of the first year. Given the high incidence of symptoms during taxane treatment and persistence of symptoms after treatment completion, it is critical to develop effective methods to predict, prevent, and treat this toxicity. Follow up of data at 104 and 156 weeks will further characterize the trajectory of long term CIPN symptoms. Funding: NIH/NCI/NCORP grant UG1CA189974

Citation Format: Meghna S. Trivedi, Joseph M. Unger, Dawn Hershman, Amy K. Darke, Daniel L. Hertz, Thomas H. Brannagan, Stephanie J. Smith, Bryan P. Schneider, William J. Irvin Jr, Amanda R. Hathaway, Amy C. Vander Woude, Vinay K. Gudena, N. Lynn Henry, Michael J. Fisch. Incidence of Acute and Persistent Clinically Meaningful Chemotherapy Induced Peripheral Neuropathy in Patients with Early-Stage Breast Cancer Receiving Taxane Therapy: SWOG S1714 (NCT# 03939481) [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr PD8-06.

Network-based assessment of HDAC6 activity predicts preclinical and clinical responses to the HDAC6 inhibitor ricolinostat in breast cancer

Inhibiting individual histone deacetylase (HDAC) is emerging as well-tolerated anticancer strategy compared with pan-HDAC inhibitors. Through preclinical studies, we demonstrated that the sensitivity to the leading HDAC6 inhibitor (HDAC6i) ricolinstat can be predicted by a computational network-based algorithm (HDAC6 score). Analysis of ~3,000 human breast cancers (BCs) showed that ~30% of them could benefice from HDAC6i therapy. Thus, we designed a phase 1b dose-escalation clinical trial to evaluate the activity of ricolinostat plus nab-paclitaxel in patients with metastatic BC (MBC) (NCT02632071). Study results showed that the two agents can be safely combined, that clinical activity is identified in patients with HR⁺/HER2^- disease and that the HDAC6 score has potential as predictive biomarker. Analysis of other tumor types also identified multiple cohorts with predicted sensitivity to HDAC6i's. Mechanistically, we have linked the anticancer activity of HDAC6i's to their ability to induce c-Myc hyperacetylation (ac-K148) promoting its proteasome-mediated degradation in sensitive cancer cells.

Lessons from the Failure to Complete a Trial of Denosumab in Women With a Pathogenic BRCA1/2 Variant Scheduling Risk-Reducing Salpingo-Oophorectomy

Female carriers of pathogenic/likely pathogenic (P/LP) BRCA1/2 variants are at increased risk of developing breast and ovarian cancer. Currently, the only effective strategy for ovarian cancer risk reduction is risk-reducing bilateral salpingo-oophorectomy (RR-BSO), which carries adverse effects related to early menopause. There is ongoing investigation of inhibition of the RANK ligand (RANKL) with denosumab as a means of chemoprevention for breast cancer in carriers of BRCA1 P/LP variants. Through the NCI Division of Cancer Prevention (DCP) Early Phase Clinical Trials Prevention Consortia, a presurgical pilot study of denosumab was developed in premenopausal carriers of P/LP BRCA1/2 variants scheduled for RR-BSO with the goal of collecting valuable data on the biologic effects of denosumab on gynecologic tissue. The study was terminated early due to the inability to accrue participants. Challenges which impacted the conduct of this study included a study design with highly selective eligibility criteria and requirements and the COVID-19 pandemic. It is critical to reflect on these issues to enhance the successful completion of future prevention studies in individuals with hereditary cancer syndromes.

Patient and Clinician Decision Support to Increase Genetic Counseling for Hereditary Breast and Ovarian Cancer Syndrome in Primary Care: A Cluster Randomized Clinical Trial

IMPORTANCE

To promote the identification of women carrying BRCA1/2 variants, the US Preventive Services Task Force recommends that primary care clinicians screen asymptomatic women for an increased risk of carrying a BRCA1/2 variant risk.

OBJECTIVE

To examine the effects of patient and clinician decision support about BRCA1/2 genetic testing compared with standard education alone.

DESIGN, SETTING, AND PARTICIPANTS

This clustered randomized clinical trial was conducted at an academic medical center including 67 clinicians (unit of randomization) and 187 patients. Patient eligibility criteria included women aged 21 to 75 years with no history of breast or ovarian cancer, no prior genetic counseling or testing for hereditary breast and ovarian cancer syndrome (HBOC), and meeting family history criteria for BRCA1/2 genetic testing.

INTERVENTIONS

RealRisks decision aid for patients and the Breast Cancer Risk Navigation Tool decision support for clinicians. Patients scheduled a visit with their clinician within 6 months of enrollment.

MAIN OUTCOMES AND MEASURES

The primary end point was genetic counseling uptake at 6 months. Secondary outcomes were genetic testing uptake at 6 and 24 months, decision-making measures (perceived breast cancer risk, breast cancer worry, genetic testing knowledge, decision conflict) based upon patient surveys administered at baseline, 1 month, postclinic visit, and 6 months.

RESULTS

From December 2018 to February 2020, 187 evaluable patients (101 in the intervention group, 86 in the control group) were enrolled (mean [SD] age: 40.7 [13.2] years; 88 Hispanic patients [46.6%]; 15 non-Hispanic Black patients [8.1%]; 72 non-Hispanic White patients [38.9%]; 35 patients [18.9%] with high school education or less) and 164 (87.8%) completed the trial. There was no significant difference in genetic counseling uptake at 6 months between the intervention group (20 patients [19.8%]) and control group (10 patients [11.6%]; difference, 8.2 percentage points; OR, 1.88 [95% CI, 0.82-4.30]; P = .14). Genetic testing uptake within 6 months was also statistically nonsignificant (13 patients [12.9%] in the intervention group vs 7 patients [8.1%] in the control group; P = .31). At 24 months, genetic testing uptake was 31 patients (30.7%) in intervention vs 18 patients (20.9%) in control (P = .14). Comparing decision-making measures between groups at baseline to 6 months, there were significant decreases in perceived breast cancer risk and in breast cancer worry (standard mean differences = -0.48 and -0.40, respectively).

CONCLUSIONS AND RELEVANCE

This randomized clinical trial did not find a significant increase in genetic counseling uptake among patients who received patient and clinician decision support vs those who received standard education, although more than one-third of the ethnically diverse women enrolled in the intervention underwent genetic counseling. These findings suggest that the main advantage for these high-risk women is the ability to opt for screening and preventive services to decrease their cancer risk.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT03470402.

A randomized, phase II trial of fulvestrant or exemestane with or without ribociclib after progression on anti-estrogen therapy plus cyclin-dependent kinase 4/6 inhibition (CDK 4/6i) in patients (pts) with unresectable or hormone receptor–positive (HR+), HER2-negative metastatic breast cancer (MBC): MAINTAIN trial

LBA1004

Background: CDK 4/6i has demonstrated benefit in progression free survival (PFS) and overall survival (OS) in pts with HR+, HER2- MBC when combined with endocrine therapy (ET). While observational data demonstrate a potential benefit of continuing CDK 4/6i and switching ET at progression, no prospective trials have evaluated this approach. We conducted a phase II, multi-center, randomized, trial to evaluate the efficacy of fulvestrant or exemestane +/- ribociclib in pts with HR+HER2- MBC whose cancer previously progressed on any CDK 4/6i + any ET. Methods: In this investigator-initiated, phase II, double-blind, placebo-controlled trial, men or women with measurable or non-measurable HR+/HER2- MBC whose cancer progressed during CDK 4/6i and ET were randomized 1:1 to fulvestrant or exemestane +/- ribociclib. Pts treated with prior fulvestrant received exemestane as ET in the randomization; if prior exemestane fulvestrant was the ET; if neither, fulvestrant or exemestane was per investigator discretion, though fulvestrant was encouraged. PFS was the primary endpoint, defined as time from randomization to progression of disease or death. A one-sided log-rank test with a sample size of 120 randomized and evaluable pts with a significance level alpha of 2.5%, achieves 80% power to detect an effect size (difference in PFS) of 3 months. Results: Of the 120 randomized evaluable pts, 1 pt was removed due to not taking ET along with ribociclib/placebo. All but 1 pt was female, the median age was 57.0 years, 88 pts (74%) were white, and 21 (17.6%) were Hispanic. For ET, 99 pts received fulvestrant (83%) and 20 pts exemestane (17%). In terms of prior CDK 4/6i, 100 pts previously received palbociclib (84%), 13 pribociclib (11%), 2 abemaciclib (2%), and 4 palbociclib and another CDK 4/6i (3%). There was a statistically significant PFS improvement for pts randomized to fulvestrant or exemestane + ribociclib [median: 5.33 months, 95% CI (Confidence Interval): 3.25–8.12 months] vs. placebo (median: 2.76 months, 95% CI: 2.66–3.25 months): Hazard Ratio (HR) = 0.56 (95% CI: 0.37-0.83), p = 0.004. Similar results were seen in the subset of pts treated with fulvestrant, with a median PFS for those randomized to ribociclib (5.29 months) vs. placebo (2.76 months), HR = 0.59 (95% CI: 0.38-0.91), p = 0.02. At 6 months, 42% were progression-free on the ribociclib arm vs. 24% on placebo. At 12 months, 25% were progression-free on the ribociclib arm vs. 7% on placebo. Additional endpoints will be reported, including overall response rate and safety. Conclusions: In this randomized, placebo-controlled trial, there was a significant PFS benefit for pts with HR+/HER2- MBC to switch ET and receive ribociclib after progression on CDK 4/6i. Clinical trial information: NCT02632045.

Evaluation of a pharmacist-led video consultation to identify drug interactions among patients initiating oral anticancer drugs

1592

Background: The past decade has seen a dramatic increase in the number of oral anti-cancer drug (OACD) approvals in the United States. Though polypharmacy and drug-drug interactions (DDIs) likely contribute to OACD toxicity, the prevalence of these features in patients on OACDs remains largely unknown. We aimed to evaluate a one-time 30-minute pharmacist-led video consultation among metastatic cancer patients initiating OACDs to identify medication list inaccuracies as well as the prevalence, characteristics, and severity of OACD-related potential DDIs. Methods: We conducted a single-arm, prospective telehealth intervention study among 29 patients initiating OACDs to evaluate a one-time 30-minute pharmacist-led video consultation. The video visits focused on identifying and discussing polypharmacy and potential DDIs, and pharmacists then communicated recommendations to each patient's oncologist. We estimated the prevalence, characteristics (QTc prolongation, absorption interactions, etc.), and severity of OACD-related potential DDIs. Lexicomp and Micromedex were used to assess potential DDIs and measure severity on a standardized scale (A – D, X). In addition, we assessed the prevalence of medication list inaccuracies, polypharmacy, and patient satisfaction. Results: Twenty-five patients completed the intervention (86% completion rate) of whom 40% were 75 years of age or older and 60% were men. The majority were white (68%) and non-Hispanic (76%). Sixteen patients (68%) had a solid tumor diagnosis. Nearly half (48%) were insured by Medicare. The median number of medications per patient was 9 with a range of 4 – 21, and 96% of patients had at least 5 prescriptions listed. The median number of medication list errors was 2 with a range of 0 – 16, with at least 1 error for 76% and more than 1 error for 52% of patients. Pharmacists identified potential OACD-related interactions in 9 cases (40%). These included change in drug absorption or metabolism (7), QTc prolongation (1), hypotension (1), and bleeding (1). Interactions were classified as either category C (8) or D (2), requiring close monitoring or a change in treatment, respectively. All patients expressed a high level of satisfaction with the video visit. Conclusions: Polypharmacy, medication list errors, and potential DDIs are prevalent among patients initiating OACDs despite use of an electronic medical record requiring medication reconciliation. Our study suggests that a one-time remote 30-minute pharmacist-led video consultation can effectively identify and address OACD-related potential DDIs, which may decrease medication complexity and improve adherence in this population.

A phase I/II trial evaluating the safety and efficacy of eribulin in combination with copanlisib in patients with metastatic triple-negative breast cancer (TNBC)

TPS1128

Background: Metastatic (met) TNBC remains a clinical challenge with limited treatment options and inevitable chemoresistance. Aberrant PI3K pathway signaling is frequently observed in TNBC. Increasing evidence shows PI3K pathway activation maintains the stemness and chemoresistance of BC stem cells (CSCs), and PI3K inhibition sensitizes CSCs to chemotherapy (chemo). Eribulin (E), a non-taxane microtubule dynamics inhibitor, showed survival benefit in met HER2 negative BC. Preclinically, E impacts tumor vascular remodeling, inhibits epithelial-to-mesenchymal transition and metastasis – key mechanisms implicated in PI3K inhibition resistance. Copanlisib (C), a potent pan-class I PI3K inhibitor ( i), improved anti-tumor effect in E-sensitive and resistant TNBC patient-derived xenograft models, irrespective of PIK3CA/PTEN mutation (mut) status, when combined with E. This phase I/II study is aimed to determine the safety and efficacy of E+C in pts with met TNBC. Methods: This trial includes a phase I portion with the primary objective to determine the dose limiting toxicity (DLT) and recommended phase 2 dose (RP2D) of E+C, followed by a phase II randomized portion of E+C (at RP2D) versus ( vs) E with the primary objective of progression-free survival (PFS). Key secondary objectives include objective response rate (ORR) and clinical benefit rate (CBR) [phase I]; and ORR and CBR, by arm and by PIK3CA/PTEN mut status and assessment of treatment induced target engagement [phase II]. Key exploratory objectives include analysis of genomic, proteomic and metabolomic changes as potential response biomarkers in tumor tissue and blood. Key eligibility criteria include pts with: met TNBC who progressed on ≤5 chemo lines, including anthracycline/taxane (unless contraindicated), ECOG 0-1, adequate organ function and known archival tumor PIK3CA/PTEN mut status. Key exclusions: prior E or PI3K/mTOR/AKT i, grade ≥2 neuropathy, tumor AKT mut, congenital QT prolongation, and uncontrolled diabetes or hypertension. Phase I portion will follow a 3+3 design for E+C dose escalation to enroll 18 max pts, starting at E 1.1 mg/m2 IV and C 45 mg IV on days (D) 1/8 of 21-D cycle (C) (to E 1.4 mg/m2 and C 60 mg max). RP2D will be defined as the highest dose level at which at most 1 of 6 pts experience DLT during C1. 88 pts will be randomized (1:1) in the phase II portion to E+C vs E (1.4 mg/m2 D 1/8), stratified by PTEN/PIK3CA mut status. Response assessment by Response Evaluation Criteria in solid tumors (RECIST) v1.1 will occur every 9 weeks (+/-7 D). Tumor biopsy is required at baseline and C2D1-2, and optional at progression. A sample size of 88 achieves 80% power to detect PFS difference of median PFS 6.95 vs 4 months (corresponding to a hazard ratio of 0.5755) between the 2 arms, based on 1-sided two-sample log rank test at 0.1 α level. The phase I study is actively enrolling pts. Clinical trial information: NCT04345913.

Differences in clinician and patient assessment of baseline neuropathy in patients receiving taxane-based chemotherapy enrolled to SWOG S1714 (NCT# 03939481)

12024

Background: Chemotherapy induced peripheral neuropathy (CIPN) can lead to treatment dose reduction or discontinuation and significantly impact quality of life and functional status. Clinical trials have historically excluded patients with pre-existing neuropathy. Thus, it is unknown how many patients start treatment with baseline neuropathy as well as the impact on the trajectory of neuropathy symptoms. There are several patient- and clinician-based methods to assess CIPN; however, there is no consensus on the best method to evaluate CIPN or whether clinician versus patient assessment differs at baseline. Methods: In SWOG 1714, we enrolled patients ≥ 18 years of age with Stage I-III non-small cell lung, breast, or ovarian/fallopian tube/peritoneal cancer starting treatment with a taxane. Patients with baseline neuropathy were eligible. Neuropathy was assessed with patient-reported outcomes (PROs), including the European Organization for Research and Treatment of Cancer QLQ-CIPN20 (CIPN-20) and the PRO version of the Common Terminology criteria for Adverse Events (PRO-CTCAE) for severity of and interference caused by numbness and tingling, and the clinician-assessed National Cancer Institute (NCI)-CTCAE Grading Scale Version 5.0 for nervous system disorders. Results: Of 1336 patients enrolled on S1714, 1322 (99.0%) were eligible. The median age was 55.7 years (range 23.9-85.5) and 98.9% were female. The cohort was racially/ethnically diverse with 73.6% White, 11.3% Black, 4.6% Asian, and 10.5% Other and 10.5% Hispanic/Latino. Most of the patients enrolled had breast cancer (91%) and 67 patients (5.1%) reported having a neurological condition. Paclitaxel was administered to 60.2% and docetaxel to 39.8% and 98.5% planned to start treatment with full dose of taxane. Based on clinician assessment with NCI-CTCAE, 87.6% of patients at baseline had Grade 0 peripheral sensory neuropathy, 10.2% Grade 1, 2.0% Grade 2, and 0.2% Grade 3. The mean baseline CIPN-20 sensory subscore (range 0-100, higher number indicating greater severity) was 5.68 (standard deviation 10.41). Using the PRO-CTCAE for severity of numbness and tingling, 75.4% reported no baseline symptoms, 18.2% "mild", 4.8% "moderate", 1.1% "severe", and 0.5% "very severe" symptoms. With respect to interference of numbness and tingling with daily activities, 88.5% reported “not at all”, 8.3% “a little bit”, 2.0% “somewhat”, 0.9% “quite a bit”, and 0.3% “very much”. Conclusions: In this diverse cohort of predominantly breast cancer patients, there was limited evidence of significant pre-existing neuropathy. Clinician assessments of neuropathy may underestimate the symptoms of patients, emphasizing the importance of PROs in evaluating symptoms, particularly when baseline symptom is an exclusion criterion for clinical trials. Funding: NIH/NCI/NCORP grant UG1CA189974

Association Between Genetic Testing for Hereditary Breast Cancer and Contralateral Prophylactic Mastectomy Among Multiethnic Women Diagnosed With Early-Stage Breast Cancer

PURPOSE

Increasing usage of multigene panel testing has identified more patients with pathogenic or likely pathogenic (P or LP) variants in low-moderate penetrance genes or variants of uncertain significance (VUS). Our study evaluates the association between genetic test results and contralateral prophylactic mastectomy (CPM) among patients with breast cancer.

METHODS

We conducted a retrospective cohort study among women diagnosed with unilateral stage 0-III breast cancer between 2013 and 2020 who underwent genetic testing. We examined whether genetic test results were associated with CPM using multivariable logistic regression models.

RESULTS

Among 707 racially or ethnically diverse women, most had benign or likely benign (B or LB) variants, whereas 12.5% had P or LP and 17.9% had VUS. Racial or ethnic minorities were twice as likely to receive VUS. Patients with P or LP variants had higher CPM rates than VUS or B or LB (64.8% v 25.8% v 25.9%), and highest among women with P or LP variants in high-penetrance genes (74.6%). On multivariable analysis, P or LP compared with B or LB variants were significantly associated with CPM (odds ratio = 4.24; 95% CI, 2.48 to 7.26).

CONCLUSION

Women with P or LP variants on genetic testing were over four times more likely to undergo CPM than B or LB. Those with VUS had similar CPM rates as B or LB. Our findings suggest appropriate genetic counseling and communication of cancer risk to multiethnic breast cancer survivors.

Abstract P4-11-16: Feasibility and patient satisfaction with a smartphone application to improve medication adherence among patients with breast cancer

Introduction: Low medication adherence is associated with worse outcomes among patients with breast cancer (BC). Retrospective studies have shown decreased survival in patients with BC who are non-adherent to endocrine therapy, but less is known about newer oral cancer therapies and the impact on adherence to medications for chronic non-cancer conditions. New strategies to improve global medication adherence are needed. We assessed the feasibility and patient satisfaction of the Medisafe smartphone application in the initial phase of a trial to increase global medication adherence. Methods: Patients treated with oral anti-neoplastic therapy for treatment of BC were eligible. Enrolled patients received individualized instruction on Medisafe app installation and use. The Medisafe app sends patients push notification reminders at the times specified for each of their standing oral medications. Patients self-report whether each medication dose was taken or missed directly in the app. Patients were followed for 12 weeks. The primary endpoint was feasibility, defined as completion of the 12-week study intervention. uMARS (end-user Mobile Application Rating Scale) questionnaires were used to assess patient satisfaction with the Medisafe app at week 12. The objective feedback component of the uMARS contains 16 questions and includes 4 objective quality subscales: engagement, functionality, aesthetics, and information quality. Each question is answered on a 1-5 scale (5 indicates highest satisfaction), and mean responses were used to calculate an overall satisfaction score and a satisfaction score for each subsection. Results: Between July 2020 and July 2021, 58 patients were enrolled. The mean participant age was 58 years (range 31 - 87). As of June 30,2020 20 patients reached the 12-week endpoint. Of these patients, 18 (90%) completed the 12-week intervention. Of the 17 patients who completed the uMARS questionnaire, the mean overall uMARS score of the Medisafe app was 3.8 (SD 0.6). Table 1 displays the results for the uMARS subscales, which include a mean functionality score of 4.0 (SD 0.7) and mean information quality score of 4.1 (SD 0.7). Notably, 70.6% of participants reported that the app was easy to use and clearly designed, and 76.5% reported that the app’s content was appropriately designed for its specific target audience. Of the 13 patients who reported viewing educational information within the app, 84.6% reported that the information seemed credible. Almost half of patients (43.8%) reported that the app increased their awareness of the importance of addressing health behavior. Conclusions: Our early findings suggest that the use of a smartphone application to improve medication adherence among patients with cancer is feasible, with a high rate of participant completion. Furthermore, high patient-reported satisfaction with the Medisafe app suggests acceptability to promote long-term behavior change. Table 1: Patient Reported Satisfaction with the Medisafe App Evaluated Assessed by the Objective Feedback Component of the uMARS (end-user Mobile Application Rating Scale) Questionnaire at Week 12 (n=17)

uMARS Objective ScoreMean± SDOverall3.8± 0.6  Engagement3.2± 0.8  Functionality4.0± 0.7  Performance4.2± 0.8  Ease of use4.1± 1.0  Aesthetics4.0± 0.6  Information Quality4.1± 0.7  Quality of info3.8± 0.8  Visual info4.3± 0.9  Credibility4.5± 0.8

Citation Format: Melissa K Accordino, Sophie Ulene, Erin Honan, Meghna S Trivedi, Katherine D Crew, Erik Harden, Cynthia Law, Dawn L Hershman. Feasibility and patient satisfaction with a smartphone application to improve medication adherence among patients with breast cancer [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr P4-11-16.

Abstract P3-02-04: Prediction of breast cancer response to neoadjuvant chemotherapy in different biological breast cancer subtypes using diffuse optical tomography

Background: Optical-based imaging modalities play an important role in assessing breast tissue composition by measuring optical property contrast from endogenous chromophores. The advantages of optical techniques are the use of non-ionizing radiation, ease of use, and relatively low cost. The primary objective of this study is to examine changes in optically derived parameters (i.e., deoxy-hemoglobin concentration, ctHHb) from different breast cancer subtypes under neoadjuvant chemotherapy (NAC), and correlate with tumor pathologic complete response (pCR). Methods: This retrospective study evaluated 89 tumors in total divided into three distinct subtypes: HR+/HER2- (n=34), HER2+ (n=27), and TNBC (n=28). All patients were imaged at baseline, before starting NAC (TP0), and two weeks after receiving one cycle of taxane-based chemotherapy (TP1). HER2+ breast cancer patients also received HER2-target therapy. pCR was defined as complete absence of invasive carcinoma in the breast and lymph node(s) (ypT0/is ypN0 Mx) at the time of surgery. Whole breast volume was imaged by a diffuse optical tomography breast imaging system (DOTBIS) using low-intensity near-infrared light. ctHHb tumor volume concentration was normalized by the non-affected health tissue ctHHb mean value (ctHHbN). For each molecular subgroup, we conducted an independent-samples t-test to determine if there was a difference in ctHHbN levels at TP1 compared to TP0 between patients with a pCR and non-pCR. Significance was assumed at a confidence interval of 95% (α = 0.05). Results: In total, 69 patients were imaged with DOTIBS at both time points, TP0 and TP1. HR+/HER2-, TNBC and HER2+ accounted for 32% (n=23), 37% (n=22) and 30% (n=22), respectively. The ratio between ctHHbN levels measured at TP1 and TP0 was statistically significantly lower in the pCR group than non-pCR for the HER2+ and HR+/HER2- molecular subgroups, Table 1.

Conclusion: Aligned to the current practices in breast cancer management based on the characterization of breast cancer subtypes, our work evaluated changes in DOTBIS optically derived features and pCR status for different subtypes. We observed that ctHHbN levels change after two weeks of NAC and these changes are modifiable according to pCR status and are dependent on immunophenotype.

Table 1.Ratio between ctHHbN levels measured at TP1 and TP0 between pCR and non-pCR according to different molecular subtypes.Molecular SubtypepCR (mean ± SD )non-pCR (mean ± SD )p-valueHR+/HER2- (n=23)0.77 ± 0.22 (n=6)1.14 ± 0.24 (n=17).01HER2+ (n=24)0.74 ± 0.30 (n=15)1.54 ± 0.98 (n=9).04TNBC (n=22)0.96 ± 0.38 (n=4)1.29 ± 0.37 (n=18).18Bold values indicate statistical significance at p&lt;.05 level.

Citation Format: Mirella L Altoe, Kevin M Kalinsky, Hua Guo, Hanina Hibshoosh, Mariella Tejada, Katherine D Crew, Melissa K Accordino, Meghna S Trivedi, Alessandro Marone, Hyun K Kim, Andreas H Hielscher, Dawn L Hershman. Prediction of breast cancer response to neoadjuvant chemotherapy in different biological breast cancer subtypes using diffuse optical tomography [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr P3-02-04.

Abstract P5-17-12: First-in-human expansion study of oral PMD-026 in metastatic triple negative breast cancer patients

Background: Durably effective therapeutic options remain elusive for metastatic triple negative breast cancer (mTNBC) patients. RSK is a novel target kinase for mTNBC, given its integral role in the MAPK/PDK-1 pathways. PMD-026, uniquely developed for TNBC, is a first-in-class, potent, oral RSK inhibitor that constitutes a promising avenue of treatment for mTNBC. PMD-026 demonstrated a favorable safety profile and initial signs of clinical benefit in metastatic breast cancer patients in Phase I. The current expansion is investigating PMD-026 in mTNBC patients whose disease has progressed on standard therapy. Methods: This open-label study evaluates the safety and efficacy of single agent PMD-026 in mTNBC patients. Target accrual for this study is a minimum of 20 mTNBC patients dosed at 200 mg q 12 hours who have measurable disease. A food effect (FE) sub-study is enrolling a total of 12 patients with a two-arm crossover design. Exploratory biomarker analysis of tumor tissue is being assessed for activated RSK2 levels. Exploratory objectives are to understand TNBC heterogeneity, with a view to identify patients who may benefit from PMD-026 optimally. Results: Based on the trial results thus far from 25 patients, PMD-026 continues to be well-tolerated with no G4 treatment-related adverse events. The noted toxicities include low incidence of elevated ALT/AST, rash, colitis or low-grade nausea. There has been no hair loss, myelosuppression or peripheral neuropathy. Given that TNBC is such a heterogeneous disease, we sought to identify subsets of patients with extensive prior therapy (≥ 5 lines) who may benefit from PMD-026 as a monotherapy. Based on ongoing analyses in the Phase I and Ib, patients diagnosed with TNBC at their initial diagnosis (de novo TNBC) stayed on study 3-4 times longer than patients who were initially treated for HR+ or HER2+ breast cancer but lost HR or HER2 expression to become TNBC (secondary TNBC). In addition, de novo TNBC patients treated at the recommended phase II dose (RP2D) of 200 mg BID with an H score for RSK2 ≥ 180 had a median progression free survival (PFS) of 3.3 months (n=3). In contrast, patients with an H score &lt; 180 had a median PFS of 0 months (n=3). Furthermore, the PFS of 3.3 months on PMD-026 is longer than the PFS of 1.7 months in a similar population of TNBC patients on chemotherapy, where the average number of prior treatments was 3a. . Conclusions: Updated safety, clinical activity, PK, and biomarker analyses will be presented. Clinical trial information: NCT04115306.aBardia et al, N Engl J Med 2021; 384:1529-154

Citation Format: Muralidhar Beeram, Judy S. Wang, Lida A. Mina, Pavani Chalasani, Rebecca A. Shatsky, Robert Wesolowski, Sara A. Hurvitz, Meghna S. Trivedi, Hyo S. Han, Amita Patnaik, My-my Huynh, Aarthi Jayanthan, Mary Rose Pambid, Lambert Yue, Gerrit Los, Sandra E. Dunn, Andrew Dorr. First-in-human expansion study of oral PMD-026 in metastatic triple negative breast cancer patients [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr P5-17-12.

Abstract P4-11-33: Continuous glucose monitoring and hyperglycemia during chemotherapy for early-stage breast cancer

Background: There are a growing number of breast cancer (BC) survivors who are at risk for short and long-term treatment-related toxicities. BC survivors may be at higher risk of developing diabetes mellitus (DM), and chemotherapy may potentiate this risk due to concurrent corticosteroid use. DM is associated with both short and long-term treatment toxicities and worse BC outcomes. The prevalence of hyperglycemia (HG) during chemotherapy for early-stage BC (ESBC), and the association between HG during chemotherapy and treatment-related toxicities is unknown. Methods: We are conducting a single-arm pilot study to evaluate the prevalence of hyperglycemia among patients with ESBC during chemotherapy (NCT04473378). Patients are eligible if ≥18 years old, initiating chemotherapy with corticosteroid use, not receiving systemic steroids except as supportive care for chemotherapy, and known DM is allowed if patients are not treated with insulin. Within 7 days of chemotherapy initiation, the Freestyle Libre Pro (Abbott Diabetes Care) continuous glucose monitoring system is applied to the posterior arm of each participant. Patches are reapplied every 2-3 weeks and worn continuously until chemotherapy completion (duration per regimen). The Freestyle Libre Pro monitors interstitial glucose every 15 minutes via subcutaneous sensor filaments adhered to the skin without a finger prick. Data is downloaded using a wireless scan of the sensor by a reader. The primary endpoints are: 1) the prevalence of HG, defined as the number of participants who have ≥1 glucose value (fasting or non-fasting) of ≥140 mg/dL at any point from chemotherapy initiation to completion; 2) Among participants who develop HG, the proportion of time in which they have HG, measured as the number of hyperglycemic values (glucose value of ≥140 mg/dL) divided by the total number of glucose values recorded in an individual for the duration of chemotherapy. Secondary endpoints include the prevalence of impaired glucose tolerance (hemoglobin A1c [HgbA1c] ≥5.7%) prior to chemotherapy initiation in patients without a history of DM, and changes in glucose biomarkers (HgbA1c, fructosamine, and serum creatinine) during treatment. Results: Between December 2020 and April 2021, 7 patients were enrolled, with evaluable data for 5 patients. At baseline median age was 60 (range, 37-74) and median BMI was 33.0 (range, 24.6-41.6). Chemotherapy regimens were: docetaxel/cyclophosphamide (40%); docetaxel/cyclophosphamide/trastuzumab/pertuzumab (20%); weekly paclitaxel (20%); and paclitaxel followed by doxorubicin/cyclophosphamide (20%). All patients (100%) developed hyperglycemia. Of 18,768 sensor readings (281,265 minutes) the proportion of time participants were hyperglycemic (≥140 mg/dL) during the period of adjuvant/neoadjuvant chemotherapy was 22.1%, and the mean time from first corticosteroid administration to first hyperglycemic episode was 7.6 hours. Of three patients with no history of DM (including one patient with glucose intolerance), the proportion of time spent hyperglycemic (≥140 mg/dL) was 9.9% (range, 1.7-13.8%), and the mean daily glucose was 106.7 mg/dL (SD 10.3). Of the two patients with DM, the proportion of time spent hyperglycemic was 70.2% (range, 67.2-79.5%) and the mean daily glucose was 171.7 mg/dL (SD 3.1). Changes in glucose biomarkers will be presented with the full cohort. Conclusion: Hperglycemia during chemotherapy occurred in 100% of the cohort, including those without a history of DM or glucose intolerance. It is currently unknown if HG during chemotherapy is a modifiable risk factor for short and long-term BC treatment toxicities including neuropathy. Understanding glucose trends in this setting will help determine a successful intervention for HG during chemotherapy which may reduce short and long-term treatment toxicities.

Citation Format: Melissa K Accordino, John H Spivack, Sophie Ulene, Erin Honan, Meghna S Trivedi, Katherine D Crew, Erik Harden, Cynthia Law, Dawn L Hershman. Continuous glucose monitoring and hyperglycemia during chemotherapy for early-stage breast cancer [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr P4-11-33.

Abstract P4-11-04: A randomized adaptive sequential selection trial of cryotherapy, compression therapy, and placebo to prevent taxane inducted peripheral neuropathy in patients with breast cancer

Background: Taxane-induced peripheral neuropathy (TIPN) is one of the most common and debilitating adverse effects of taxane therapy for early-stage breast cancer (ESBC). TIPN is difficult to treat, and there are no known effective prevention strategies. Small non-randomized studies in patients with ESBC, have suggested both cryotherapy and compression therapy to the hands and feet may be effective for TIPN prevention. However, is unknown which therapy, if either, is more effective at prevention of TIPN compared to placebo. Methods: We conducted a randomized phase IIB adaptive sequential selection trial of cryotherapy vs. compression therapy vs. placebo among participants with ESBC during taxane chemotherapy (NCT03873272). Participants were randomized in triplets to either frozen gloves/socks [NatraCure] refrigerated for at least 3 hours to -25 to -30°C prior to use (cryotherapy); compression gloves/socks [Sigvaris] with a pressure of 20-30 mmHg on the upper extremity, 20-30 mmHg on the lower leger, and 15 mmHg on the toes/feet (compression therapy); or “loose” gloves/socks [Sigvaris] with a maximum pressure of 3 mmHg on the upper/lower extremities (placebo arm). All garments were worn for a total of 90-120 minutes, beginning 15 minutes prior to the start of taxane infusion and until 15 minutes after completion of the taxane infusion. The primary goal was to select the best intervention to be carried forward to a larger phase III trial, with a high probability of correct selection if one intervention is truly superior using a novel sequential design based on the Levin-Robbins-Leu family of sequential selection procedures. The primary endpoint was change in Functional Assessment of Cancer Therapy Neurotoxicity (FACT-NTX) at 12-weeks; success was defined as &lt;5-point decrease from baseline (minimal TIPN). The tally of success was compared starting from the 15th triplet. An arm would be eliminated if it had ≥4 successes less than the leading arm. The trial stopped the first time two arms were eliminated. Secondary endpoints included staff assessed adherence (defined as wearing study garments for ≥80% of infusions) and patient reported comfort (4-point Likert scale) to the study intervention. Results: Between 4/2019-4/2021 64 patients were randomized (n=20 cryotherapy; n=22 compression therapy; n=22 placebo). The stopping criterion was met after the 17th triplet (51 patients) had been evaluated for the primary endpoint. For the 51 patients, the median age was 50 years (range, 28-78), and the majority of patients (58.8%) were treated with docetaxel every 3-weeks, whereas 41.2% were treated with weekly paclitaxel. Success (i.e., minimal TIPN) at 12-weeks occurred in 11 (64.7%) patients treated with compression therapy, 7 (41.1%) patients treated with cryotherapy, and 7 (41.1%) patients treated with placebo. Adherence to the study intervention occurred in 82.4% of patients treated with compression therapy, 29.4% of patients treated with cryotherapy, and 76.5% treated with placebo. In regards to comfort, 87.4% of patients treated with compression therapy reported being satisfied/very satisfied with the study garments, compared to 56.3% treated with cryotherapy, and 73.3% treated with placebo. Conclusion: Compression therapy was found to be the most effective and tolerable intervention in this phase IIB selection trial to prevent TIPN, and has the greatest probability of being a successful intervention to prevent TIPN in a future randomized phase III study. Cryotherapy was not successful, which is likely related to poor tolerability due to the cold, which resulted in poor adherence to the study garments. Compression therapy for the prevention of TIPN should be further evaluated in a larger randomized phase III study.

Citation Format: Melissa K Accordino, Shing Lee, Cheng-Shiun Leu, Meghna S Trivedi, Katherine D Crew, Kevin M Kalinsky, Rohit Rajhunathan, Alessandra Taboada, Lauren Franks, Erin Honan, Erik Harden, Cynthia Law, Dawn L Hershman. A randomized adaptive sequential selection trial of cryotherapy, compression therapy, and placebo to prevent taxane inducted peripheral neuropathy in patients with breast cancer [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr P4-11-04.

Diagnosis of Leptomeningeal Metastasis in Women With Breast Cancer Through Identification of Tumor Cells in Cerebrospinal Fluid Using the CNSide™ Assay

INTRODUCTION

Diagnosis of LM is limited by low sensitivity of cerebrospinal fluid (CSF) cytopathology. Detecting tumor cells in CSF (CSF-TCs) might be more sensitive. We evaluated if CNSide (CNSide), a novel assay for tumor cell detection in CSF, can detect CSF-TCs better than conventional CSF cytology.

METHODS

We enrolled adults with metastatic breast cancer and clinical suspicion for LM to undergo lumbar puncture (LP) for CSF cytopathology and CNSide. CNSide captured CSF-TCs using a primary 10-antibody mixture, streptavidin-coated microfluidic channel, and biotinylated secondary antibodies. CSF-TCs were assessed for estrogen receptor (ER) expression by fluorescent antibody and HER2 amplification by fluorescent in situ hybridization (FISH). CSF cell-free DNA (cfDNA) was extracted for next-generation sequencing (NGS). Leptomeningeal disease was defined as positive CSF cytology and/or unequivocal MRI findings. We calculated sensitivity and specificity of CSF cytology and CNSide for the diagnosis of LM.

RESULTS

Ten patients, median age 51 years (range, 37-64), underwent diagnostic LP with CSF evaluation by cytology and CNSide. CNSide had sensitivity of 100% (95% Confidence Interval [CI], 40%-100%) and specificity of 83% (95% CI, 36%-100%) for LM. Among these patients, concordance of ER and HER2 status between CSF-TCs and metastatic biopsy were 60% and 75%, respectively. NGS of CSF cfDNA identified somatic mutations in three patients, including one with PIK3CA p.H1047L in blood and CSF.

CONCLUSIONS

CNSide may be a viable platform to detect CSF-TCs, with potential use as a diagnostic tool for LM in patients with metastatic breast cancer. Additional, larger studies are warranted.

Patient Knowledge and Expectations About Return of Genomic Results in a Biomarker-Driven Master Protocol Trial (SWOG S1400GEN)

PURPOSE

Biomarker-driven master protocols represent a new paradigm in oncology clinical trials, but their complex designs and wide-ranging genomic results returned can be difficult to communicate to participants. The objective of this pilot study was to evaluate patient knowledge and expectations related to return of genomic results in the Lung Cancer Master Protocol (Lung-MAP).

METHODS

Eligible participants with previously treated advanced non-small-cell lung cancer were recruited from patients enrolled in Lung-MAP. Participants completed a 38-item telephone survey ≤ 30 days from Lung-MAP consent. The survey assessed understanding about the benefits and risks of Lung-MAP participation and knowledge of the potential uses of somatic testing results returned. Descriptive statistics and odds ratios for associations between demographic factors and correct responses to survey items were assessed.

RESULTS

From August 1, 2017, to June 30, 2019, we recruited 207 participants with a median age of 67, 57.3% male, and 94.2% White. Most participants "strongly/somewhat agreed" with statements that they "received enough information to understand" Lung-MAP benefits (82.6%) and risks (69.5%). In items asking about potential uses of Lung-MAP genomic results, 87.0% correctly indicated that the results help to select cancer treatment, but < 20% correctly indicated that the results are not used to confirm cancer diagnosis, would not reveal risk of developing diseases besides cancer, and would not indicate if family members had increased cancer risk. There were no associations between sociodemographic factors and proportions providing correct responses.

CONCLUSION

In a large National Clinical Trials Network biomarker-driven master protocol, most participants demonstrated incorrect knowledge and expectations about the uses of genomic results provided in the study despite most indicating that they had enough information to understand benefits and risks.

Integration of germline multigene panel testing into breast and gynecologic oncology clinics

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Background: Germline genetic testing plays an important role in informing cancer screening and risk-reducing strategies, as well as treatment decisions with PARP inhibitors for BRCA-associated malignancies. Referrals to clinical genetics for pre-test counseling and results disclosure can be delayed due to financial and logistical barriers, which may ultimately delay clinical decision-making. Our study objective was to understand patient attitudes, knowledge, and anxiety/distress with point-of-care (POC) genetic testing in breast and gynecologic oncology clinics. Methods: We enrolled patients with early-stage breast cancer undergoing neoadjuvant treatment, metastatic breast cancer, ovarian cancer, or endometrial cancer undergoing POC multigene panel testing with their primary oncologist, rather than a genetic counselor. Pre-test counseling came from discussion with their primary oncologist. Participants completed a survey at time of genetic testing and one after return of genetic test results. Validated measures of genetic testing knowledge, cancer-related distress, and attitudes towards genetic testing were included. Descriptive statistics were generated for all data collected and paired t-tests were conducted for baseline and follow-up comparisons. Results: We enrolled 106 subjects, of which 97 completed the baseline survey. All participants were female with a mean age of 61.5 years (SD 13.5). The cohort consisted of participants with the following tumor types: 80 breast, 2 ovarian, and 16 endometrial. Almost 44% of women identified as Hispanic/Latina, 55% had highest level of education of community/technical college or less, and 51.2% reported annual incomes of less than $50,000. Forty-seven percent of participants had adequate baseline genetic testing knowledge scores (defined as at least 50% correct responses). A majority of participants (86.6%) had positive attitudes toward undergoing genetic testing. Results of genetic testing revealed 11 participants (11.3%) with pathogenic or likely pathogenic variants (of which 36.3% were in BRCA1/2), 25 (25.8%) with variants of unknown significance (VUS), and 61 (62.9%) with benign or likely benign results. The mean cancer-related distress score (scale from 15 to 60, higher score indicates higher levels of distress) was 32.78 (SD 9.74) at baseline and 26.5 (SD 8.9) after receiving genetic testing results (p = 0.002). Genetic test results informed cancer treatment decisions regarding medications and surgery in 15% and 13% of patients, respectively, the majority of which were breast cancer patients. Conclusions: As genetic testing is more frequently used for clinical decision-making it is important to develop ways to efficiently integrate POC testing in the oncology clinics. We demonstrated that POC genetic testing for breast and gynecologic cancers is feasible and can inform clinical decision-making.

Racial and Ethnic Differences in BRCA1/2 and Multigene Panel Testing Among Young Breast Cancer Patients

Genetic testing for hereditary breast and ovarian cancer (HBOC) is recommended for breast cancer patients diagnosed at age ≤ 50 years. Our objective was to examine racial/ethnic differences in genetic testing frequency and results among diverse breast cancer patients. A retrospective cohort study among women diagnosed with breast cancer at age ≤ 50 years from January 2007 to December 2017 at Columbia University in New York, NY. Among 1503 diverse young breast cancer patients, nearly half (46.2%) completed HBOC genetic testing. Genetic testing completion was associated with younger age, family history of breast cancer, and earlier stage, but not race/ethnicity or health insurance status. Blacks had the highest frequency of pathogenic/likely pathogenic (P/LP) variants (18.6%), and Hispanics and Asians had the most variants of uncertain significance (VUS), 19.0% and 21.9%, respectively. The percentage of women undergoing genetic testing increased over time from 15.3% in 2007 to a peak of 72.8% in 2015. Over the same time period, there was a significant increase in P/LP and VUS results. Due to uncertainty about the clinical implications of P/LP variants in moderate penetrance genes and VUSs, our findings underscore the need for targeted genetic counseling education, particularly among young minority breast cancer patients.

First-in-human phase 1/1b expansion of PMD-026, an oral RSK inhibitor, in patients with metastatic triple-negative breast cancer

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Background: P90 ribosomal S6 kinase (RSK) is an actionable molecular target against metastatic triple negative breast cancer (mTNBC). RSK is a major convergence point in the integral TNBC signaling pathways, MAPK and PDK-1. PMD-026 is a first-in-class oral RSK inhibitor with high selectivity. The dose escalation portion of this study established the RP2D of PMD-026 as 200 mg Q12. PMD-026 demonstrated good plasma exposure following oral dosing, with a T1/2 of ̃ 6 h (range 4-8 h), and achieved the targeted preclinical efficacious concentrations using a Q12h dosing schedule. PMD-026 also demonstrated a tolerable safety profile and initial signs of efficacy in patients with metastatic breast cancer. The intensity of RSK2 activation ranged from an H Score of 110-268 based on a CLIA companion immunohistochemistry assay. We present initial data from the expansion cohort. Methods: The primary aim of this single-arm, open-label, first-in-human phase 1/1b study is to evaluate the safety of single agent PMD-026 in patients with mTNBC. Secondary endpoints are clinical activity, pharmacokinetics, and correlative biomarker expression on tumor specimens. Patients are dosed at 200 mg twice daily in 21-day cycles. Eligible patients have measurable disease as per RECIST v1.1 and have had disease progression on or after standard of care treatment. Tumor tissue is assessed to retrospectively correlate RSK2 activity by immunohistochemistry (IHC) with clinical outcomes. Pharmacokinetics are assessed along with a food effect (sub-study with n=12). In addition, a pharmacodynamic marker, YB-1 phosphorylation, is being explored in peripheral blood mononuclear cells before and during treatment. Results: As of February 16, 2021, 7 patients with mTNBC (median age 62 years, range 33-74) have been enrolled in the phase 1b Expansion (median of 7 prior lines of therapy). Notable prior therapies in the phase 1b include sacituzumab govitecan (n=4) and atezolizumab/nab-paclitaxel (n=1). Patients in escalation and expansion treated with the RP2D had median progression free survival of 30 vs 99 days for low vs high RSK2 expression, respectively. This cut-off will be further evaluated in the expansion phase of the study. Conclusions: Updated safety, clinical activity, pharmacokinetic, and biomarker analyses will be presented. Target accrual for phase 1b Expansion is a minimum of 20 patients with mTNBC. Clinical trial information: NCT04115306.

Changes in Diffuse Optical Tomography Images During Early Stages of Neoadjuvant Chemotherapy Correlate with Tumor Response in Different Breast Cancer Subtypes

PURPOSE

This study's primary objective was to evaluate the changes in optically derived parameters acquired with a diffuse optical tomography breast imaging system (DOTBIS) in the tumor volume of patients with breast carcinoma receiving neoadjuvant chemotherapy (NAC).

EXPERIMENTAL DESIGN

In this analysis of 105 patients with stage II-III breast cancer, normalized mean values of total hemoglobin ([Formula: see text]), oxyhemoglobin ([Formula: see text]), deoxy-hemoglobin concentration ([Formula: see text]), water, and oxygen saturation ([Formula: see text]) percentages were collected at different timepoints during NAC and compared with baseline measurements. This report compared changes in these optical biomarkers measured in patients who did not achieve a pathologic complete response (non-pCR) and those with a pCR. Differences regarding molecular subtypes were included for hormone receptor-positive and HER2-negative, HER2-positive, and triple-negative breast cancer.

RESULTS

At baseline, [Formula: see text] was higher for pCR tumors (3.97 ± 2.29) compared with non-pCR tumors (3.00 ± 1.72; P = 0.031). At the earliest imaging point after starting therapy, the mean change of [Formula: see text] compared with baseline ([Formula: see text]) was statistically significantly higher in non-pCR (1.23 ± 0.67) than in those with a pCR (0.87 ± 0.61; P < 0.0005), and significantly correlated to residual cancer burden classification (r = 0.448; P < 0.0005). [Formula: see text] combined with HER2 status was proposed as a two-predictor logistic model, with AUC = 0.891; P < 0.0005; and 95% confidence interval, 0.812-0.969.

CONCLUSIONS

This study demonstrates that DOTBIS measured features change over time according to tumor pCR status and may predict early in the NAC treatment course whether a patient is responding to NAC.

Care Delivery Impact of the COVID-19 Pandemic on Breast Cancer Care

PURPOSE

COVID-19 has altered healthcare delivery. Previous work has focused on patients with cancer and COVID-19, but little has been reported on healthcare system changes among patients without COVID-19.

METHODS

We performed a retrospective study of patients with breast cancer (BC) in New York City between February 1, 2020, and April 30, 2020. New patients were included as were patients scheduled to receive intravenous or injectable therapy. Patients with COVID-19 were excluded. Demographic and treatment information were obtained by chart review. Delays and/or changes in systemic therapy, surgery, radiation, and radiology related to the pandemic were tracked, along with the reasons for delay and/or change. Univariate and multivariable analysis were used to identify factors associated with delay and/or change.

RESULTS

We identified 350 eligible patients, of whom 149 (42.6%) experienced a delay and/or change, and practice reduction (51.0%) was the most common reason. The patients who identified as Black or African American, Asian, or Other races were more likely to experience a delay and/or change compared with White patients (Black, 44.4%; Asian, 47.1%; Other, 55.6%; White, 31.4%; P = .001). In multivariable analysis, Medicaid compared with commercial insurance (odds ratio [OR], 3.04; 95% CI, 1.32 to 7.27) was associated with increased odds of a delay and/or change, whereas stage II or III BC compared with stage I (OR, 0.38; 95% CI, 0.15 to 0.95; and OR, 0.28; 95% CI, 0.08 to 0.092, respectively) was associated with decreased odds of a delay and/or change.

CONCLUSION

Almost half of the patients with BC without COVID-19 had a delay and/or change. We found racial and socioeconomic disparities in the likelihood of a delay and/or change. Further studies are needed to determine the impact these care alterations have on BC outcomes.

Abstract PS8-08: Impact of genetic testing for hereditary breast cancer on screening and risk-reducing surgeries among multi-ethnic breast cancer survivors

Introduction Current guidelines for cancer risk management for hereditary breast cancer focus on individuals with pathogenic/likely pathogenic variants (P/LP) in high penetrance genes. There is little consensus on prophylactic mastectomy for low/moderate penetrance genes or variants of uncertain significance (VUS). Furthermore, many guidelines for enhanced breast cancer screening are targeted to unaffected carriers, but not breast cancer survivors. Given the increasing use of multigene panel testing, more patients are receiving results of P/LP in low/moderate penetrance genes or VUSs. We aimed to investigate how multigene panel results impacted surgical and screening decisions among breast cancer patients. Methods We conducted a retrospective analysis of women diagnosed with stage 0-III breast cancer at Columbia University Irving Medical Center in 2013 or later, who received germline genetic testing. Clinical data were extracted from the electronic health record (EHR), tumor registry, and genetic testing portals. Patients were excluded if they had stage IV disease at diagnosis, had bilateral mastectomy before 2013, or had missing genetic test results or surgical reports. For the screening analysis, patients were excluded if they had bilateral mastectomy or did not have breast imaging in the EHR. Surgery type was defined by the most advanced breast surgery received. Enhanced screening was defined as use of breast ultrasound or MRI in the absence of breast symptoms and in the setting of a normal mammogram. Univariable and multivariable analyses were performed to assess the association between clinical factors and receipt of bilateral mastectomy or enhanced screening. Results Among 715 evaluable women, about two-thirds were 50 years or younger, with 45% white, 12% black, 27% Hispanic, 11% Asian, and 4% other. Most patients (69.5%) had benign/likely benign (B/LB) genetic test results, while 91 (12.7%) had P/LP and 127 (17.8%) had VUS. VUS rates were higher among racial/ethnic minorities (27% Asian, 25% Hispanic, 19% black) compared to white women (10%). About 31% of women underwent bilateral mastectomy, 25% unilateral mastectomy, and 45% lumpectomy. Bilateral mastectomy rates among patients with P/LP variants were higher compared to those with VUS or B/LB results (66% vs. 27% vs. 26%), particularly P/LP in high-penetrance genes (76%) compared to other genes (45%). On multivariable analysis, compared to patients with B/LB genetic results, P/LP was significantly associated with bilateral mastectomy (odds ratio [OR]=5.72, 95% confidence interval [CI]=3.43-9.53). Younger age at diagnosis and family history of breast cancer were also associated with bilateral mastectomy. Among patients with breast cancer screening data, almost half (43%) received enhanced screening (59% ultrasound, 25% MRI, 16% both). On multivariable analysis, patients with P/LP variants and age of diagnosis under 50 were more likely to receive enhanced screening (OR=4.43, 95% CI=1.59-12.33 and OR=1.92, 95% CI=1.09-3.38, respectively). Hispanic women compared to non-Hispanic whites and those with Medicaid rather than private health insurance were less likely to undergo enhanced screening. Conclusions We demonstrated that detection of P/LP variants on multigene panel testing influences surgical and screening decisions among breast cancer patients. Patients with VUS, a group enriched for racial/ethnic minorities, appropriately have similar surgical and screening decisions as those with B/LB results. Our findings suggest adequate genetic counseling and communication of cancer risk to multi-ethnic breast cancer survivors.

Citation Format: Vicky Ro, Tarsha Jones, Meghna S Trivedi, Julia E McGuinness, Thomas Silverman, Wendy K Chung, Rita Kukafka, Katherine D Crew. Impact of genetic testing for hereditary breast cancer on screening and risk-reducing surgeries among multi-ethnic breast cancer survivors [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr PS8-08.

The COVID-19 pandemic impact on breast cancer care delivery at an academic center in New York City

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Background: The coronavirus disease 2019 (COVID-19) pandemic has altered healthcare delivery. To save resources and reduce patient exposure, non-urgent care has been postponed. Previous work has focused on cancer patients with COVID-19, but little has been reported on the impact on patients without COVID-19. We aimed to characterize breast cancer (BC) patients without COVID-19 whose care was impacted by the COVID-19 pandemic at an academic center in New York City. Methods: We performed a retrospective cohort study of BC patients treated at a medical oncology practice between 2/1/2020-4/30/2020. Patients were included if they were scheduled to receive intravenous or injectable therapy or were scheduled as a new patient. Patients were excluded if they tested positive for COVID-19 or transferred care during the study period. Demographic and treatment information were obtained by chart review. Delays/changes in systemic therapy, imaging, interventional radiology procedures, radiation, and surgery were tracked. Delays were defined as postponements of scheduled care. Changes were defined as care alterations without postponements. Care impact was defined as any change/delay in any of the above oncologic care a patient was scheduled for. We conducted a univariate analysis to compare demographics and care impact using χ2 analyses. Results: Of 351 eligible patients, the majority had stage 0-III BC (71.9%) and hormone receptor-positive HER2-negative BC (69.5%). Less than half were Caucasian (43.9%). Care was impacted due to the pandemic in 149 (42.5%) of patients. Surgery changes/delays were most frequent (37 of 84 patients, 44.0%), followed by changes/delays in systemic therapy (90 of 351 patients, 25.6%) and imaging (58 of 282 patients, 20.6%). Patients of Asian, Black, and other non-reported races were more likely to experience a care impact vs. Caucasian patients (47.1% vs. 44.4% vs. 55.6% vs. 31.2%, p = 0.001). Hispanic patients were more frequently impacted vs. non-Hispanic patients (47.6% vs. 35.9%, p = 0.06). Medicaid and Medicare patients were also more frequently impacted vs. commercially insured patients (54.7% vs. 41.4% vs. 36.2%, p = 0.02). BC stage and hormone receptor status were not significantly associated with care impacts. Conclusions: We found that nearly half of our BC patients experienced a change/delay in workup or treatment during the COVID-19 pandemic. We also found significant racial and socioeconomic disparities in the likelihood of care impact. Ongoing studies will determine the impact of alterations in care on cancer outcomes.

Letrozole + ribociclib versus letrozole + placebo as neoadjuvant therapy for ER+ breast cancer (FELINE trial)

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Background: Ribociclib (R) + letrozole (L) is superior to L in metastatic breast cancer (BC). Preoperative endocrine prognostic index (PEPI) score 0 after neoadjuvant endocrine therapy (NET) is associated with low risk of relapse without chemotherapy in ER+ BC. On-therapy change in Ki-67 predicts adjuvant recurrence. FELINE is a biomarker-based multicenter randomized trial comparing changes in Ki-67 and PEPI between L+ Placebo (P) & L+R. Methods: Postmenopausal women with >2 cm or node+ ER+ HER2- BC were randomized 1:1:1 between L+P, L+R 400 mg continuous dose (Rc) and L+R 600 mg, 3 weeks on/1 week off - intermittent dose (Ri). Treatment was continued for six 28-day cycles. Core biopsies, blood samples were obtained at baseline, Day 14 cycle 1 (D14C1), and surgery. Clinical measurement, mammogram and US were obtained at baseline, surgery; MRI at baseline, week 8. Primary endpoint was rate of PEPI score 0 between L+P and L+R (i+c combined). Other endpoints were change in centrally performed Ki-67, complete cell cycle arrest (CCCA): Ki-67 <2.7%, clinical/imaging response, and difference in response & toxicity between the two R (Rc and Ri) arms. Results: From 2/2016 to 8/2018, 120 women were enrolled at 9 US centers. Thirty-eight were randomized to L+P and 82 to L+R groups (41 in Ri and Rc). Treatment groups were balanced at baseline. PEPI score of 0 was equal (25%) in L+P & L+R groups. CCCA at D14C1 was observed in 52% vs. 92% in L+P, L+R respectively (p < 0.0001). CCCA at surgery was observed in 63.3% vs. 71.4% in L+P, L+R respectively (p = NS). A significant increase in Ki-67 was observed between D14C1 and surgery in 66% vs. 33% in L+R, L+P respectively (p = 0.006). There was no difference in clinical, mammographic, US or MRI response between L+P and L+R. CCCA at D14C1 and surgery was similar in Ri & Rc arms. Grade >3 AEs were observed in 4 (10%) patients in L+P, 23 (56%) in L+Ri, 19 (46%) in L+Rc arms. Conclusions: Addition of R to L as NET did not result in more women with a PEPI score of 0. At D14C1 twice as many women on L+R had CCCA compared to L+P (92% vs 52%). However, significantly more women on L+R had increased proliferation between D14C1 and surgery , resulting in similar CCCA at surgery. Correlative studies are being performed to determine mechanisms of on-therapy acquired resistance to ribociclib. Continuous and intermittent doses of R have similar efficacy, toxicity. Clinical trial information: NCT02712723 . [Table: see text]

Diagnosis of leptomeningeal metastasis (LM) through identification of circulating tumor cells (CTCs) in cerebrospinal fluid (CSF)

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Background: Diagnosis of LM from solid tumors can be challenging. The TargetSelector (TS) CTC detection assay has demonstrated highly specific and sensitive CTC capture both for epithelial (CK+) and non-epithelial (CK-) subsets. The assay utilizes a ten-antibody (ab) capture cocktail followed by biotinylated secondary abs that bind to CTCs, enriched in a microfluidic device. TS targeted next-generation sequencing (NGS) assay detects somatic mutations in 12 breast cancer-related genes. The aim was to determine whether TS can improve sensitivity in the diagnosis of LM compared to CSF cytology by lumbar puncture (LP). Methods: CSF was collected prospectively from patients (pts) with a prior solid tumor diagnosis and suspicion of LM. CTCs were isolated from CSF using the TS platform. Cells were stained with cytokeratin (CK), CD45, streptavidin and DAPI. CTCs captured in a microchannel were classified as CK + or -. Peripheral blood samples obtained at time of LP underwent similar CTC analysis. Cell-free total nucleic acids (cfTNA) were extracted from plasma and CSF followed by NGS. Data analysis used the Ion Torrent Suite with annotation and report curation by Ion Reporter and Oncomine Knowledgebase Reporter software respectively. Results: There were 14 pts (13 women and 1 man), median age 56 years (range 32-75) with cancers of the breast (10), lung (1), colon (1), CNS lymphoma (1) or glioma (1). Pts had received a median of 2.5 lines of systemic metastatic therapy (range 0-8). CSF cytology was not sent for 1 pt and TS was not performed for 1 pt. TS and standard cytology had 89% agreement in pts with metastatic breast cancer (MBC, 8/9). Of the 6 pts for whom CTCs were detected in CSF by TS, 3 pts had + cytology (all MBC), 2 pts had - cytology and 1 pt with MBC was not tested by cytology. Of the 3 pts with + CSF by cytology (all MBC), all were detected by TS (Table). Among 5 MBC pts with CTCs present in CSF, ER status was concordant in 2 of 5 (40%). HER2 status was concordant in 3 of 4 (75%) evaluable pts and not determined in 1 pt. Analysis of cfDNA from CSF identified somatic mutations in 3 pts (TP53, PIK3CA, CCND1, respectively). In 1 of 3 pts, the mutation identified in the CSF (PIK3CA) in HR+/HER2- MBC was also identified in the blood. Conclusions: TargetSelector is a viable platform for the detection of breast cancer CTCs in the CSF. NGS performed on CSF samples can identify potentially actionable mutations. [Table: see text]

Abstract P6-08-16: Evaluation of a decision aid on BRCA1/2 genetic testing in Orthodox Jewish women

Background: Ashkenazi Jews have a 1 in 40 chance of carrying a BRCA1 or BRCA2 (BRCA1/2) pathogenic variant. Our prior research has shown that Orthodox Jewish women face unique social, cultural, and religious factors that may influence uptake of BRCA1/2 genetic testing. The aim of our study was to examine the impact of a web-based decision aid (DA) on BRCA1/2 genetic testing intention/uptake in Orthodox Jewish women.

Methods: We conducted a pilot study among 50 Orthodox Jewish women in the New York/New Jersey area who were given access to the RealRisks DA and completed surveys at baseline prior to exposure to RealRisks and at 1 and 6 months after exposure to RealRisks. RealRisks is a patient-centered DA that includes family history intake, calculation of personalized breast cancer risk according to the BRCAPRO model, education about the pros and cons of genetic testing, and preference elicitation. The surveys collected information on participant demographics, health literacy, subjective numeracy, perceived breast cancer risk and BRCA1/2 mutation risk, breast cancer worry, stigma, hereditary breast and ovarian cancer (HBOC) genetic testing knowledge, autonomy, decision self-efficacy, decisional conflict, decision regret, and genetic testing intention/uptake. Descriptive statistics and paired t-tests and Chi-squared tests were conducted to assess changes in the study measures from baseline to follow-up.

Results: Fifty women completed the baseline survey, 43 (86%) the 1-month survey, and 38 (74%) the 6-month survey. Mean age was 43.9 years (standard deviation [SD] 14.6); 94% had adequate health literacy and mean numeracy score was 4.25 (SD 0.83; range, 1-6). At baseline, 74% of women had adequate HBOC genetic testing knowledge and 52% thought it was likely that they carried an altered BRCA1/2 gene. Compared to baseline, there was a significant increase in HBOC genetic testing knowledge and decrease in decisional conflict at 1 month and 6 months. There was no significant change in decision self-efficacy, autonomy, stigma, or breast cancer worry after exposure to RealRisks at 1-month or 6-month follow-up. The percentage of women who intended to complete or already completed BRCA1/2 genetic testing decreased from 54% at baseline to 30% at 1 month. At 6 months, 21% reported they had completed or intended to complete BRCA1/2 genetic testing at that time.

Conclusions: The RealRisks DA was effective at improving HBOC genetic testing knowledge and reducing decisional conflict about HBOC genetic testing; however, genetic testing intention decreased after exposure to the DA. An intervention that directly addresses the religious and cultural issues regarding genetic testing in the Orthodox Jewish community may improve BRCA1/2 genetic testing uptake and adoption of cancer prevention strategies in this population. Such an intervention will likely have to include religious, community, and medical leaders within the Orthodox Jewish community.

Changes in study measures over 3 time pointsOutcome MeasuresBaseline Mean (SD)1 month Mean (SD)p-value compared to baseline6 months Mean (SD)p-value compared to baselineHBOC geneting testing knowledge [range, 0-11]6.60 (2.18)7.74 (1.94)&lt;0.0017.24 (2.07)0.050Decision self-efficacy [range, 0-100]56.26 (15.63)55.39 (16.91)0.869Not Assessed (NA)Decisional conflict [range, 0-100]52.45 (28.43)33.93 (28.74)&lt;0.00128.29 (27.64)&lt;0.001Autonomy [range, 0-7]4.21 (1.43)4.36 (1.38)0.680NAStigma [range, 1-7]3.51 (1.15)3.25 (0.98)0.477NABreast cancer worry [range, 1-7]2.23 (1.03)2.27 (0.98)0.7672.26 (1.00)0.889HBOC genetic testing completion or intention to complete (%)54%30%0.02021%0.002

Citation Format: Meghna S Trivedi, Haley Manley, Haeseung Yi, Thomas Silverman, Wendy K Chung, Paul S Appelbaum, Rebecca Starck, Isaac Schechter, Rita Kukafka, Katherine D Crew. Evaluation of a decision aid on BRCA1/2 genetic testing in Orthodox Jewish women [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P6-08-16.

Abstract P1-19-27: Phase IB trial of ACY-1215 (ricolinostat) combined with nab-paclitaxel in metastatic breast cancer (MBC)

Background:HDAC6, a cytoplasmic histone deacetylase, impacts cell viability by influencing protein metabolism, microtubule dynamics, and chaperone function. ACY-1215 is an orally active, selective HDAC6 inhibitor. Preclinical studies have demonstrated ACY-1215 to have synergistic activity with taxanes. We have developed an algorithm (HDAC6 score) based on mRNA expression profiling to evaluate the HDAC6 activity of individual tumor samples. Methods: In this open-label phase Ib trial, patients (pts) received ACY-1215 PO daily for 21 days of each 28-day cycle with nab-paclitaxel 100 mg/m2 on days 1, 8, and 15 until progression of disease or unacceptable toxicity. Entry criteria included men or women with any MBC subtypes. Measurable diseae was not required. The primary objective was to establish the maximum tolerated dose (MTD) of ACY-1215 with nab-paclitaxel. Dose escalation employed a time-to-event continual reassessment method (TITE-CRM) and the MTD was defined as the dose combination associated with a target probability of dose limiting toxicity (DLT) of 0.25.The TITE-CRM used an empirical dose-toxicity model (n=16 evaluable pts), starting at 120 mg to a maximum dose of 240 mg daily (qd). HDAC score was performed retrospectively on primary and/or metastatic tissue.Results:Seventeen pts were accrued between March 2016-Feb 2018; 16 were evaluable. Of evaluable pts, the median age was 57.5 years (range: 41-78), 14 were female (87.5%), 3 had triple negative MBC, and 13 hormone receptor (HR)+/HER2- MBC. The mean number of prior lines was 4 (range: 0-9). The first pt started at 120 mg qd, the second at 180 mg qd, and the rest at 240 mg qd. No DLTs were seen in the DLT window, and thus the MTD was not reached. Grade III events related to nab-paclitaxel included neutropenia (n=1), peripheral neuropathy (n=1), and 1 grade IV neutropenia. Grade III syncope related to ACY-1215 was observed in 2 pts. In the 16 evaluable pts, the following were best responses: 1 partial response (PR), 11 stable disease (SD), and 4 progressive disease (PD: 2 TNBC, 2 HR+/HER2-). One patient with SD remains on treatment since Feb 2018 (17 months). Median progression free survival (PFS) was 5.3 months [95% confidence interval (CI): 4.45-11.0]. In evaluable pts with accessible tissue (n=9), pts with high HDAC6 score (n=6: cutoff &gt; -0.1) had a significantly improved PFS compared to low HDAC6 score (n=3, HR: 1.2-115, 6.6 months vs. 2.0 months, respectively p=0.01). Conclusions: ACY-1215 240 mg qd is safe and tolerable with weekly nab-paclitaxel. Clinical activity has been observed, with the majority of pts demonstrating SD and 1 with a PR. In this phase 1b trial, high HDAC6 score associates with longer PFS. HDAC6 score should be evaluated in larger trials as a predictor of response to HDAC6 inhibition.

Citation Format: Kevin Kalinsky, Cody Chiuzan, Maika Onishi, Meghna S Trivedi, Melissa Accordino, Tizita Zeleke, Qingfei Pan, Sean Kelly, Erin Honan, Ruby Wu, Kathleen Fenn, Katherin D Crew, Dawn L Hershman, Matthew Maurer, Jiyang Yu, Jose Silva. Phase IB trial of ACY-1215 (ricolinostat) combined with nab-paclitaxel in metastatic breast cancer (MBC) [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P1-19-27.

Abstract P1-01-02: Early changes in diffuse optical tomography predicts pathologic complete response to neoadjuvant chemotherapy in triple-negative breast cancer

Background: Optical based imaging modalities have shown promise for monitoring tumor response to neoadjuvant chemotherapy (NAC) in patients with breast cancer (BC). Patients with triple negative BC (TNBC) who achieve a pathologic complete response (pCR) have improved disease free and overall survival after NAC. In this study, we evaluated whether early changes in diffuse optical tomography breast imaging system (DOTBIS) parameters can predict a pCR. In particular, we studied total hemoglobin concentration (ctHbT) in the tumor region.

Methods: This is a retrospective evaluation of 105 stage II-III BC patients enrolled in a prospective cohort study between 2011 and 2019. All patients received standard taxane-based chemotherapy in the neoadjuvant setting and pCR was defined as no invasive tumor cells from the breast and axillary tissue at surgery (ypT0 ypN0). Residual Cancer Burden (RCB) score was also calculated. By imaging the whole breast volume using low intensity near infrared light, we measured tissue concentration of oxy-hemoglobin (ctO2Hb) and deoxy-hemoglobin (ctHHb). After tumor volume segmentation, the mean ctHbT (ctO2Hb+ ctHHb) extracted from the region of interest was normalized by the non-tumor region ctHbT mean value. We conducted an independent-samples t-test to determine if there was a difference in changes in the normalized ctHbT levels at week 4 (w4) between patients with a pCR and non-pCR. A Pearson's correlation assessed for correlation between RCB score and changes in the normalized ctHbT level at w4 compared to baseline.

Results: In total, 77 patients had complete data for the analysis. Of these, TNBC accounted for 18% (14/77) of BC cases. DOTBIS data was acquired at baseline for all patients. Twelve patients received weekly paclitaxel x 12, followed by dose-dense adriamycin/cyclophosphamide every 2 weeks x 4, and two received docetaxel/cyclophosphamide every 3 weeks x 6. Ten of 14 TNBC patients were imaged after four weeks of taxane-based NAC (w4). Of the 14 TNBC patients, 6 (43%) achieved pCR. Two patients were classified as RCB-I, 5 as RCB-II, and 1 non-pCR patient without an available RCB. After comparing normalized ctHbT levels at w4 to baseline, NAC was associated with an overall decrease of 28% for the pCR group (n=5) as opposed to an increase of 67% for non-pCR (n=5). The normalized ratio between ctHbT levels measured at w4 and baseline was statistically lower in the pCR group (0.72 ± 0.28) than non-pCR (1.67 ± 0.83) (95% CI, 0.17 to 2.09), p = .043. Changes in the normalized ctHbT levels after 4 weeks of NAC were strongly correlated to RCB score (r = .833, p = .005).

Conclusions: This study demonstrates that changes as early as 4 weeks in DOTBIS-measured ctHbT levels in patients with TNBC receiving NAC correlate strongly with pathologic response. If further validated on a larger set, these data could potentially be used to optimize treatment outcomes or improve personalized therapeutic strategies.

Citation Format: Mirella L Altoe, Kevin Kalinsky, Hua Guo, Hanina Hibshoosh, Mariella Tejada, Katherine D Crew, Melissa K Accordino, Meghna S Trivedi, Alessandro Marone, Hyun K Kim, Andreas H Hielscher, Dawn L Hershman. Early changes in diffuse optical tomography predicts pathologic complete response to neoadjuvant chemotherapy in triple-negative breast cancer [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P1-01-02.

Mental Illness and BRCA1/2 Genetic Testing Intention Among Multiethnic Women Undergoing Screening Mammography

OBJECTIVES

To examine associations between patient-reported mental illness diagnosis and symptoms and BRCA1/2 genetic testing intention among women undergoing screening mammography.

SAMPLE & SETTING

100 multiethnic women of lower socioeconomic status who were undergoing mammography screening and met family history criteria for BRCA1/2 genetic testing.

METHODS & VARIABLES

Descriptive and bivariate nonparametric statistics and multivariate logistic regression were used to examine associations between mental illness and genetic testing intention. Variables were anxiety, depression, patient-reported mental illness diagnosis and symptoms, and testing intention.

RESULTS

Prevalence rates of mental illness symptoms were 36% for clinically significant depression and 36% for anxiety. Although 76% of participants intended to undergo genetic testing, only 5% had completed testing. History of mental illness and elevated levels of anxiety and depressive symptoms were positively correlated with testing intention in the bivariate analysis. In multivariate analysis, only younger age and less education were associated with testing intention.

IMPLICATIONS FOR NURSING

Future studies should address psychosocial needs and other competing barriers at the patient, provider, and healthcare system levels to increase access to BRCA1/2 genetic testing among multiethnic women.

Study protocol: Randomized controlled trial of web-based decision support tools for high-risk women and healthcare providers to increase breast cancer chemoprevention

BACKGROUND

Chemoprevention using selective estrogen receptor modulators and aromatase inhibitors has been shown to reduce invasive breast cancer incidence in high-risk women. Despite this evidence, few high-risk women who are eligible for chemoprevention utilize it as a risk-reducing strategy. Reasons for low uptake include inadequate knowledge about chemoprevention among patients and healthcare providers, concerns about side effects, time constraints during the clinical encounter, and competing comorbidities.

METHODS/DESIGN

We describe the study design of a randomized controlled trial examining the effect of two web-based decision support tools on chemoprevention decision antecedents and quality, referral for specialized counseling, and chemoprevention uptake among women at an increased risk for breast cancer. The trial is being conducted at a large, urban medical center. A total of 300 patients and 50 healthcare providers will be recruited and randomized to standard educational materials alone or in combination with the decision support tools. Patient reported outcomes will be assessed at baseline, one and six months after randomization, and after their clinic visit with their healthcare provider.

DISCUSSION

We are conducting this trial to provide evidence on how best to support personalized breast cancer risk assessment and informed and shared decision-making for chemoprevention. We propose to integrate the decision support tools into clinical workflow, which can potentially expand quality decision-making and chemoprevention uptake.

TRIAL REGISTRATION

NCT03069742.

Implementation and uptake of an interactive virtual online tumor board across NCI-Cancer Centers

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Background: Expert knowledge is often shared among academic oncologists at tumor boards (TBs) at National Cancer Institute Designated Cancer Centers (NCI-CCs), but not documented or made accessible to community oncologists. Using an oncologist-only question and answer (Q&A) website, we sought to disseminate expert insights from TBs at NCI-CCs to provide educational benefit to the oncology community. Methods: A process was designed with faculty at 11 NCI-CCs to document and share discussions from TBs focused on areas of clinical complexity and practice variation on theMednet.org, an interactive Q&A website of over 8,700 US oncologists. One faculty member from each TB was selected as a site leader. She or he distilled discussions about patient management from the TB into a question that addressed the clinical situation being discussed. After the question was posted, faculty at the participating NCI-CCs were asked to answer the question on theMednet. Answers were peer reviewed, indexed, stored and disseminated via email newsletters to registered oncologists. Community engagement was measured by Q&A page views, upvotes of Q&A, and poll participation. Results: A total of 15 Breast, Thoracic, and Gastrointestinal programs from 11 NCI-CCs participated. Between 12/2016 and 5/2019, faculty highlighted 146 questions from their TBs. Q&A were viewed 43,291 times by 3,585 oncologists including 2,264 community oncologists. One hundred and eighty-four answers are posted by 56 academic physicians and peer reviewed by 76 academic physicians. One hundred and eighty-five publications were cited. Community oncologists upvoted Q&A 808 times and voted in 45 polls related to the questions 1,667 times. Viewership of NCI-CC Q&A increased by 419% over time. Q&A were repeatedly searched and viewed, with 90% of all TB Q&A viewed every month. Conclusions: Via the online Q&A theMednet platform, NCI-CC providers effectively made expert knowledge easily accessible to community oncologists across the US. Timely access to evidence based recommendations from expert faculty can inform future practice choices in the community.

[Table: see text]

A standardized workflow to improve the consent process among patients initiating an oral anticancer drug

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Background: The American Society of Clinical Oncology and The Oncology Nursing Society’s guidelines recommend that consent be obtained and patient education provided prior to oral anticancer drug (OACD) initiation. The aim of this quality improvement project was to improve documentation rates of consent and education prior to OACD initiation in an outpatient breast oncology clinic. Methods: Plan-Do-Study-Act (PDSA) methodology was used to identify the root causes of inadequate OACD documentation; and to evaluate a standardized OACD workflow that included a multidisciplinary (physician, nurse practitioner [NP], and administrative staff) checklist on the disposition sheet and standardized patient education material, used in the Columbia University Irving Medical Center Breast Oncology Clinic. New OACD prescriptions were identified in the electronic health record (EHR) from 2/1/18-4/1/18 (pre-intervention) and 6/5/18-8/17/18 (post-intervention). Documentation of consent and education were evaluated by EHR review. Consent (yes/no) was determined by physician documentation in either the corresponding clinic note or scanned consent form, and education (yes/no) was determined by NP documentation in the education section of the clinic note. Documentation rates were compared pre- and post-intervention. Results: Pre-intervention, 19 patients received a new OACD, and 0 (0%) had documentation of consent or patient education. Root cause analysis revealed the driver of inadequate documentation was the inability to identify patients with a new OACD prescription at the time of their clinic visit. After implementation of the OACD workflow, 23 patients initiated a new OACD, 15 (65.0%) had documentation of consent and 7 (30.0%) had OACD education documented in the EHR. Conclusions: After the first PDSA cycle, documentation of consent and education improved from baseline. However, improvement in both metrics are still needed. Patient volume, staff changes, and the format of the OACD checklist may have limited the efficacy of this intervention. In the next PDSA cycle, the consent process will be linked to the required OACD pre-approval process to further increase OACD documentation.

Phase 1 Study of Erlotinib and Metformin in Metastatic Triple-Negative Breast Cancer

BACKGROUND

Epidermal growth factor receptor (EGFR) is frequently overexpressed in metastatic triple-negative breast cancer (mTNBC). One strategy for overcoming resistance to EGFR inhibition is concomitant inhibition of downstream signaling. The antidiabetic drug metformin inhibits both MAPK and PI3K/mTOR pathway signaling. We evaluated the combination of erlotinib and metformin in a phase 1 study of patients with mTNBC.

PATIENTS AND METHODS

Patients with mTNBC who had received at least one prior line of therapy for metastatic disease were eligible. Erlotinib dose was fixed at 150 mg daily. Metformin dose escalation was planned according to a 3 + 3 design. Dose-limiting toxicities (DLT) were assessed during the first 5 weeks of therapy. The primary objective was to determine the maximum tolerated dose of metformin with fixed-dose erlotinib. Secondary endpoints were response rate, stable disease rate, and progression-free survival.

RESULTS

Eight patients were enrolled. The median number of prior therapies for metastatic disease was 2.5 (range, 1-6). No DLT events were reported during the DLT assessment period. Most adverse events were grade 1/2. Grade 3 diarrhea despite maximum supportive care required dose reduction of metformin in one patient. Grade 3 rash led to study withdrawal in one patient. No grade 4 adverse events were reported. The best observed response was stable disease in 2 patients (25%). Median progression-free survival was 60 days (range, 36-61 days).

CONCLUSION

Erlotinib and metformin were well tolerated in a population of pretreated mTNBC patients but did not demonstrate efficacy in this population.

Understanding Factors Associated with Uptake of BRCA1/2 Genetic Testing among Orthodox Jewish Women in the USA Using a Mixed-Methods Approach

BACKGROUND/AIMS

Ashkenazi Jews have a 1:40 prevalence of BRCA1/2 mutations. Orthodox Jews are an understudied population with unique cultural and religious factors that may influence BRCA1/2 genetic testing uptake.

METHODS

Using a mixed-methods approach, we conducted a cross-sectional survey and focus groups among Orthodox Jewish women in New York/New Jersey to explore factors affecting decision-making about BRCA1/2 genetic testing.

RESULTS

Among 321 evaluable survey participants, the median age was 47 years (range, 25-82); 56% were Modern Orthodox and 44% Yeshivish/Chassidish/other; 84% were married; 7% had a personal history of breast or ovarian cancer. Nearly 20% of the women had undergone BRCA1/2genetic testing. Predictors of genetic testing uptake included being Modern Orthodox (odds ratio [OR] = 2.31), married (OR = 3.49), and having a personal or family history of breast or ovarian cancer (OR = 9.74). Focus group participants (n = 31) confirmed the importance of rabbinic consultation in medical decision-making and revealed that stigma was a prominent factor in decisions about BRCA1/2 testing due to its potential impact on marriageability.

CONCLUSION

In order to increase the uptake of BRCA1/2 genetic testing among the Orthodox Jewish population, it is crucial to understand religious and cultural factors, such as stigma and effect on marriageability, and engage religious leaders in raising awareness within the community.

Uptake of genetic testing for germline BRCA1/2 pathogenic variants in a predominantly Hispanic population

Genetic counseling is under-utilized in women who meet family history criteria for BRCA1 and BRCA2 (BRCA1/2) testing, particularly among racial/ethnic minorities. We evaluated the uptake of BRCA1/2 genetic testing among women presenting for screening mammography in a predominantly Hispanic, low-income population of Washington Heights in New York City. We administered the Six-Point Scale (SPS) to women presenting for screening mammography at Columbia University Irving Medical Center (CUIMC) in the Washington Heights neighborhood of New York, NY. The SPS is a family history screener to determine eligibility for BRCA1/2 genetic testing based upon U.S. Preventive Services Task Force (USPSTF) guidelines that has been validated in low-income, multiethnic populations. Among women who underwent screening mammography at CUIMC between November 2014 and June 2016, 3,055 completed the SPS family history screener. Participants were predominantly Hispanic (76.7%), and 12% met family history criteria for BRCA1/2 testing, of whom <5% had previously undergone testing. In a multiethnic population, a significant proportion met family history criteria for BRCA1/2 testing, but uptake of genetic testing was low. Such underutilization of BRCA1/2 genetic testing among minorities further underscores the need to develop programs to engage high-risk women from underrepresented populations in genetic testing services.

BRCA1/2 and multigene panel testing among metastatic breast, pancreas, prostate, and ovarian cancer patients

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Background: Given the availability of targeted therapies such as PARP inhibitors, patients with metastatic breast, pancreas, prostate, and ovarian cancer are recommended to have germline genetic testing for hereditary cancer syndromes. Completion of genetic testing among this population is understudied. Methods: We performed a retrospective study of 548 patients with stage 4 breast, pancreas, prostate, and ovarian cancer at diagnosis from January 2013-December 2017 identified in the New York Presbyterian Hospital Tumor Registry at Columbia University Irving Medical Center. Data on socio-demographics, clinical factors, and genetic testing completion and results were collected from the medical record. We conducted descriptive statistics. Results: Our study population had a median age of 66 years (range, 23-97) at diagnosis; 61% female; 50% non-Hispanic white/22% Hispanic/15% non-Hispanic black/5% Asian/7% other; 33% private insurance/16% Medicaid/44% Medicare/7% unknown insurance. Primary cancer was 24% breast, 8% ovary, 61% pancreas, and 7% prostate. Only 38 patients were seen by a genetic counselor (7%) and only 50 (9%) had genetic testing performed. Among those who underwent germline testing, 92% had multigene panel testing (median number of genes tested 13.5, range 2-74). Pathogenic variants were detected in 6 patients (12%), of which 4 had a BRCA1/2 mutation, and 26% had a variant of uncertain significance (VUS). Conclusions: We found that only a small percentage of metastatic breast, pancreas, prostate, and ovarian cancer patients underwent genetic testing. Further research is necessary to identify the barriers to genetic testing uptake in metastatic cancer patients. BRCA1/2 and multigene panel testing has important implications in this patient population not only for treatment decisions, but also to increase cascade testing in unaffected family members who may be at risk for malignancy in the future.

Abstract P5-09-01: Racial/ethnic differences in BRCA1/2 and multigene panel testing among young breast cancer patients

Background: Breast cancer (BC) patients diagnosed at age 50 and under are recommended to have germline genetic testing for hereditary BC due to a high likelihood of carrying a pathogenic mutation in a moderate or high penetrance risk gene. Completion of genetic testing among racial/ethnic minorities, particularly multigene panel testing, is understudied. We examined predictors of completion of BRCA1/2 and multigene panel testing among women with early onset BC and assessed racial/ethnic differences in genetic testing completion and results.

Methods: We performed a retrospective cohort study of 1370 BC patients diagnosed at &lt;50 years of age at Columbia University Medical Center (CUMC) from January 2007-December 2016.Data on socio-demographics, clinical factors, and genetic testing completion and results were collected from the medical record. We conducted descriptive statistics and univariate and multivariable logistic regression models.

Results: Our study population had a median age of 44 years (range, 19-50); 44% non-Hispanic white, 24% Hispanic, 13% non-Hispanic black, 10% Asian, 9% other; 61% private insurance, 22% Medicaid, 17% other. Nearly half of the women (N=607; 44.3%) had genetic testing performed. In the multivariable regression model, genetic testing completion was less likely with increasing age at diagnosis (odds ratio [OR]=0.93; 95% confidence interval [CI]=0.91-0.95) and stage 0 or 4 BC compared to stage 1 (OR=0.67; 95% CI=0.46-0.97 and OR=0.35; 95% CI=0.19-0.64, respectively). Completion of genetic testing was more likely with a family history of BC (OR=5.55; 95% CI=3.92-7.87). Genetic testing completion did not vary by race/ethnicity or insurance coverage. Across all racial/ethnic groups, the frequency of pathogenic/likely pathogenic variants identified was 13.0% and 10.5% had at least 1 variant of uncertain significance (VUS). The highest VUS frequency was among Asians (21.2%). The percentage of women undergoing genetic testing increased over time from 18.5% in 2007 and reached a peak of 69.3% in 2015. From 2007 to 2016, the percentage of pathogenic/likely pathogenic variants detected increased from 3.4% to 9.1% and the VUS frequency rose from 3.4% to 13.3% with increasing use of panel testing.

Frequency of pathogenic variants and VUS among women ≤ 50 years diagnosed with BC at CUMC (2007-2016) Pathogenic variantsVUSTotal81 (5.9%)74 (5.4%)BRCA144 (3.2%)10 (0.7%)BRCA221 (1.5%)10 (0.7%)ATM3 (0.2%)9 (0.6%)CHEK23 (0.2%)8 (0.5%)Other variants detected in: APC, BARD1, BRIP1, CDH1, CDKN2A, MEN1, MLH1, MRE11A, MSH2, MSH6, MUTYH, NBN, NF1, PALB2, PHOX2B, PMS2, POLE, PTEN, RAD50, RAD51C, SDHA, STK11, TP53

Conclusions and Relevance: Nearly half of the women with early onset BC had genetic testing. We did not observe disparities in genetic testing by race/ethnicity or insurance coverage. Genetic testing completion, as well as the frequency of pathogenic/likely pathogenic variants and VUS detection, increased over time as panel testing replaced BRCA1/2 testing. Counseling on the likelihood of obtaining uncertain results should be provided to all patients undergoing hereditary BC genetic testing, particularly to racial/ethnic minorities.

Citation Format: Trivedi MS, Jones T, Jiang X, Underhill ML, Bose S, Silverman T, Chung WK, Kukafka R, Crew KD. Racial/ethnic differences in BRCA1/2 and multigene panel testing among young breast cancer patients [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P5-09-01.

Abstract P1-20-02: Incidence of hyperglycemia in non-diabetic patients with early-stage breast cancer treated with chemotherapy

Background: There are shared risk factors between breast cancer (BC) and diabetes mellitus (DM). BC treatments including chemotherapy given in combination with glucocorticoids can induce hyperglycemia and steroid related DM. Patients with DM are at increased risk of developing chemotherapy related toxicities such as chemotherapy induced peripheral neuropathy (CIPN) compared to those without DM. The incidence of hyperglycemia during chemotherapy in non-diabetic patients with early-stage breast cancer is unknown.

Methods: We performed a retrospective analysis of non-diabetic women with stage I-III breast cancer treated with chemotherapy at Columbia University Medical Center from 9/1/2016-8/31/2017 to evaluate hyperglycemia incidence during chemotherapy and up to six months after chemotherapy completion. Eligible patients were identified in the electronic health record (EHR) by ICD9 and 10 codes (ICD9 174.x and ICD10 C50.x) and a record of chemotherapy administration. Non-diabetic patients were defined by chart review as no recorded history of diabetes and no receipt of a diabetes medication in the EHR. Breast cancer stage was determined by chart review. Glucose values were recorded prior to chemotherapy, during chemotherapy, and for six-months after chemotherapy completion. We defined hyperglycemia as a glucose value of ≥200 mg/dl. Median time to hyperglycemia was also calculated.

Results: We identified 82 eligible patients. The majority of patients received dexamethasone during their chemotherapy course (79 patients, 96.3%). The most frequent chemotherapy regimen was doxorubicin/cyclophosphamide and paclitaxel (32 patients, 39.0%). At baseline, 20 patients (24.4%) had a normal body mass index (BMI), 27 patients (32.9%) were overweight, and 31 patients (37.8%) were obese. Hyperglycemia occurred in 8 patients (9.8%) after initiation of chemotherapy. Among patients with hyperglycemia, the maximum blood glucose was between 200-299 mg/dl in seven patients (87.5%), and between 500-599 in one patient (12.5%). The median time to hyperglycemia was 84 days. Among patients who did not experience hyperglycemia, the maximum blood glucose was between 140-159 mg/dl in six patients (8.1%), between 160-179 mg/dl in eight patients (10.8%), and between 180-199 mg/dl in three patients (4.1%). Three patients were diagnosed with DM following chemotherapy completion.

Conclusion: Hyperglycemia occurred in almost 10% of non-diabetic patients who received chemotherapy for early-stage breast cancer. Additionally, over 30% of patients had a blood glucose of 140 mg/dl or higher after chemotherapy initiation. The impact of hyperglycemia on the development of chemotherapy related toxicities in this group is unknown. Future research is needed to identify effective interventions for glucose control during chemotherapy, and to determine if glucose control during treatment can reduce the risk of chemotherapy related toxicities, specifically CIPN.

Citation Format: Accordino MK, Lin A, Wright JD, Trivedi MS, Kalinsky K, Crew KD, Hershman DL. Incidence of hyperglycemia in non-diabetic patients with early-stage breast cancer treated with chemotherapy [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P1-20-02.

Abstract P6-18-35: A phase 1 study of erlotinib and metformin in advanced triple negative breast cancer

Background: The epidermal growth factor receptor (EGFR) is frequently overexpressed in triple negative breast cancer (TNBC). However, EGFR inhibitors have not shown efficacy as monotherapy in TNBC. One strategy for overcoming resistance to EGFR inhibition is concomitant inhibition of downstream signaling. Metformin is a LKB1-dependent AMPK activator that inhibits both MAPK and AKT signaling. The combination of the EGFR inhibitor erlotinib and metformin synergistically induces apoptosis in TNBC cell lines and decreases tumor burden in PTEN-null EGFR-amplified mouse xenograft models. We evaluated the combination of erlotinib and metformin in a phase 1 study of patients with advanced TNBC.

Methods: Patients with advanced TNBC who had received at least one prior line of therapy for metastatic disease were eligible. Erlotinib dose was fixed at 150mg daily. Metformin dose escalation was planned according to a 3+3 design, beginning at 850mg BID and escalating to 850mg TID. One de-escalation to 500mg BID was allowed. Dose-limiting toxicities (DLT) were assessed during the first five weeks of therapy. The primary objectives were to determine the maximum tolerated dose (MTD) of metformin with fixed dose erlotinib and to determine the potential for clinical benefit. Secondary endpoints were response rate, stable disease rate, and progression free survival. Pre- and on-treatment skin biopsies were collected to determine the effect of the study drugs on their respective cell signaling targets, particularly EGFR, AMPK, and mTOR.

Results: Between March 2013 and May 2015, nine patients were screened and eight were enrolled. Median age was 48 years (range 37-79). Median number of prior therapies for metastatic disease was 2.5 (range 1-6). No DLT events were reported in either of the dose escalation cohorts during the DLT assessment period. AEs occurring in three or more patients and all grade III AEs are reported in Table 1. Grade III diarrhea despite maximum supportive care required dose reduction of metformin from 850mg TID to 850mg BID in one patient. Grade III rash led to study withdrawal in one patient. No grade IV AEs were reported. Per RECIST v1.1, the best observed response was stable disease in two patients (25%). Median time on study was 2.0 months (range 1.2-3.0). Skin biopsy marker assessment is ongoing and will be reported.

Conclusion: The combination of erlotinib and metformin was generally well tolerated in a population of pre-treated metastatic TNBC patients. No unexpected toxicities occurred. While no responses were achieved, stable disease was observed in patients who received this non-chemotherapy combination.

Adverse EventsEventMetformin 850mg BID n=3Metformin 850mg TID n=5All patients n=8 Number of patients (percent) All gradesGrade IIIAll gradesGrade IIIAll gradesGrade IIIRash3 (100)1 (33.3)5 (100)08 (100)1 (12.5)Diarrhea3 (100)05 (100)2 (40.0)8 (100)2 (25.0)Weight loss1 (33.3)05 (100)06 (75.0)0Dry skin1 (33.3)05 (100)06 (75.0)0Nausea2 (66.7)03 (60.0)05 (62.5)0Vomiting1 (33.3)03 (60.0)04 (50.0)0Dry mouth1 (33.3)03 (60.0)04 (50.0)0Dysgeusia1 (33.3)02 (40.0)03 (37.5)0Increased creatinine2 (66.7)01 (20.0)03 (37.5)0Fatigue1 (33.3)02 (40.0)03 (37.5)0Anorexia1 (33.3)02 (40.0)03 (37.5)0Hyponatremia1 (33.3)1 (33.3)001 (12.5)1 (12.5)

Citation Format: Fenn KM, Maurer MA, Lee SM, Crew KD, Trivedi MS, Accordino MK, Hershman DL, Kalinsky K. A phase 1 study of erlotinib and metformin in advanced triple negative breast cancer [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P6-18-35.