Adjuvant nivolumab, capecitabine or the combination in patients with residual triple-negative breast cancer: the OXEL randomized phase II study

Chemotherapy and immune checkpoint inhibitors have a role in the post-neoadjuvant setting in patients with triple-negative breast cancer (TNBC). However, the effects of nivolumab, a checkpoint inhibitor, capecitabine, or the combination in changing peripheral immunoscore (PIS) remains unclear. This open-label randomized phase II OXEL study (NCT03487666) aimed to assess the immunologic effects of nivolumab, capecitabine, or the combination in terms of the change in PIS (primary endpoint). Secondary endpoints included the presence of ctDNA, toxicity, clinical outcomes at 2-years and association of ctDNA and PIS with clinical outcomes. Forty-five women with TNBC and residual invasive disease after standard neoadjuvant chemotherapy were randomized to nivolumab, capecitabine, or the combination. Here we show that a combination of nivolumab plus capecitabine leads to a greater increase in PIS from baseline to week 6 (91%) compared with nivolumab (47%) or capecitabine (53%) alone (log-rank p = 0.08), meeting the pre-specified primary endpoint. In addition, the presence of circulating tumor DNA (ctDNA) is associated with disease recurrence, with no new safety signals in the combination arm. Our results provide efficacy and safety data on this combination in TNBC and support further development of PIS and ctDNA analyses to identify patients at high risk of recurrence.

Adjuvant nivolumab, capecitabine or the combination in patients with residual triple-negative breast cancer: the OXEL randomized phase II study

Chemotherapy and immune checkpoint inhibitors have a role in the post-neoadjuvant setting in patients with triple-negative breast cancer (TNBC). However, the effects of nivolumab, a checkpoint inhibitor, capecitabine, or the combination in changing peripheral immunoscore (PIS) remains unclear. This open-label randomized phase II OXEL study (NCT03487666) aimed to assess the immunologic effects of nivolumab, capecitabine, or the combination in terms of the change in PIS (primary endpoint). Secondary endpoints include the presence of ctDNA, toxicity, clinical outcomes at 2-years and association of ctDNA and PIS with clinical outcomes. Forty-five women with TNBC and residual invasive disease after standard neoadjuvant chemotherapy were randomized to nivolumab, capecitabine, or the combination. Here we show that a combination of nivolumab plus capecitabine leads to a greater increase in PIS from baseline to week 6 (91%) compared with nivolumab (47%) or capecitabine (53%) alone (log-rank p = 0.08), meeting the pre-specified primary endpoint. In addition, the presence of circulating tumor DNA (ctDNA) was associated with disease recurrence, with no new safety signals in the combination arm. Our results provide efficacy and safety data on this combination in TNBC and support further development of PIS and ctDNA analyses to identify patients at high risk of recurrence.

Abstract P6-05-09: Cardiovascular Risk Evaluation for Breast Cancer Survivors: A Pilot Study

Introduction: Breast cancer (BC) is the most common cancer in women in the United States (US). With advances in screening and treatment, there are increasing numbers of BC survivors. Preexisting or emerging cardiovascular (CV) risk factors and some cancer therapies put BC survivors at risk for long-term CV disease (CVD). ASCO clinical practice guidelines for prevention and monitoring of cardiac dysfunction recommend treatment of CV risk factors in cancer survivors, however, the application of these guidelines in clinical practice presents several challenges. In this pilot study, we describe the feasibility of performing CVD risk assessment in a cohort of BC survivors in a single institution in an urban area that serves mostly Black/African American (AA) populations.

Methods: We identified patients with early-stage BC treated between 2015 and 2022. Patients underwent CVD risk assessment including vital signs, hemoglobin A1c, lipid panel, transthoracic echocardiogram (TTE), 6-minute walk test (6MWT), troponin T, and B-type natriuretic peptide (NT-ProBNP). The primary objective of the study was to describe the feasibility of performing a CVD risk assessment.

Results: Out of 69 eligible patients who were approached for the study, 50 were enrolled and completed the CVD risk assessment (72%). Among 19 patients who did not enroll or complete the risk assessment, time constraints to complete the work up was the predominant factor. The median age was 60.5 years (SD = 13.65; range 34-86), 76% self-identified as Black/AA, 14% as White, and 95% as Non-Hispanic. Half of the patients had hormone-receptor-positive BC, 34% human epidermal growth factor receptor 2 (HER2) positive disease (and received HER2-targeted therapies), and 28% triple-negative breast cancer (TNBC). In terms of treatment, 34% received anthracycline-containing regimens. CVD risk assessment results are shown in Table 1. Twenty-four (48%) of the patients had metabolic syndrome defined as the presence of 3 out of 5 CV risk factors (waist circumference, hypertension, low HDL, high triglycerides, insulin resistance). Although all patients had an ejection fraction (EF) above 55%, 7 patients (14%) had an abnormal global longitudinal strain (GLS). The median number of meters in the 6MWT was 369 (SD 94.46, range 67-531); 74% of patients walked a shorter distance than predicted by age and body mass index, indicating significant physical impairment. All patients had a troponin T value below the 99th percentile. The most frequent modifiable CVD-risk factors included obesity and hypertension.

Conclusion: Performing a low-cost CVD risk assessment in a population of mostly Black/AA BC survivors was feasible in this pilot study. We identified a high prevalence of CVD risk factors, with 48% of patients meeting metabolic syndrome criteria and the majority of patients demonstrated a very high level of functional impairment measured by 6MWT. Our findings underscore the importance of survivorship care focused on CVD risk in BC survivors. Limitations include the small sample size, single-institution study, and lack of CV and BC-related outcomes. The higher incidence of TNBC could be explained by a selection bias of patients receiving cytotoxic chemotherapy and the higher incidence of TNBC in the Black/AA population. Future research will focus on implementing this assessment in the survivorship clinic and establishing interventions to decrease CVD risk in cancer survivors.

Table 1. Clinical Measurements & Outcomes (n=50).

Citation Format: Ilana Schlam, Dipanjan Debnath, Christopher Gallagher, Asma A. Dilawari, Shruti R. Tiwari, Malate Aschalew, Hiwot Guebre-Xabiher, Stacy Malloy, Kristi Graves, Ana Barac, Ami Chitalia. Cardiovascular Risk Evaluation for Breast Cancer Survivors: A Pilot Study [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 P6-05-09.

Institutional review of African American (AA) patients with metastatic triple-negative breast cancer

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Background: Atezolizumab+ Abraxane (Ate+Abx) was approved as 1st line treatment in metastatic TNBC based on IMPASSION (IM) 130 trial and was subsequently withdrawn per IM131 trial. Treatment of mTNBC remains challenging. Pembrolizumab with chemotherapy received accelerated approval based on Keynote-355. Poor outcomes among AA patients (pts) are linked to biological differences, BRCA1/2 mutations, obesity, and socioeconomic barriers. In TNBC clinical trials, AA pts continue to be underrepresented, e.g., 5.8% (26) in IM130 and 4.9% (21) in IM131. Our cancer center sees over 300 new BC pts a year, and at least 50% identify as AA. Here we examine our institutional experience. Methods: IRB-approved retrospective database search was conducted between 01/01/2019- 04/16/2021 to identify 11 pts treated with Ate+Abx for mTNBC at Medstar Washington Hospital Center, DC. Demographic variables manually extracted were age, BMI, insurance type and outcomes. Results: 10/11 (91%) pts were AA with lines of therapy ranging 1-6. 20% (2/10) showed partial response (PR) on 3-month (M) interval imaging per the RECIST 1.1 scoring. PD occurred in 6/10 (60%) of pts, although PD-L1 was positive in 90% (9/10) pts. Time to progression (TTP) was 1-7 M (median 3M) compared to TTP of 5.59 to 7.46M (median 7.16M) for all races in the IM130 study. Autoimmune colitis, peripheral neuropathy, and fatigue were notable adverse effects (AEs). 2/10 (20%) pts discontinued treatment due to AEs. Colitis and neuropathy in IM130 were <1%. Mean age at drug initiation was 52.2 vs. 55 years in IM130, indicating earlier onset of mTNBC in the AA population. Conclusions: Trends of higher PD and earlier TTP were noted in our AA pts. Young age at metastasis, high number of previous lines of therapy, high number of metastatic sites, and obesity were noted amongst our AA mTNBC pts. Positive PD-L1, BRCA mutations, metastatic sites, BMI, or insurance type did not correlate with outcomes. Pts with PR vs. PD were not different in terms of insurance, metastasis sites, and BMI. Differences in AEs are noted; however, the small pt population size and lack of a control group are limitations. While the FDA has withdrawn Ate from trials for mTNBC, this study suggests a need for more AA pts to be included in clinical trials for TNBC. Lack of health care access, insufficient education, inadequate recruitment, and distrust of the medical system are contributing factors that require continued efforts.[Table: see text]

Abstract PD9-02: Peripheral immune subsets and circulating tumor DNA (ctDNA) in patients (pts) with residual triple negative breast cancer (TNBC) treated with adjuvant immunotherapy and/or chemotherapy (chemo): The OXEL study

Background: Poor clinical outcomes are noted in pts with TNBC who do not achieve a pathologic complete response (pCR). We characterized peripheral immune subsets and the role of minimal residual disease (MRD) detection via ctDNA in pts who participated in the OXEL study. Methods: OXEL (Opdivo® -XELoda ®) is a recently completed phase II open-label 3-arm randomized study of nivolumab (nivo), capecitabine (cape) or the combination as adjuvant therapy (tx) for pts with residual TNBC after appropriate neoadjuvant chemo. Residual disease was defined as ≥ 1.0 cm of primary tumor and/or nodal involvement. Eligible pts had completed definitive local tx. Pts were randomly assigned to nivo 360 mg iv q3wks x 6 (arm A); cape 1250mg/m2 po bid D1-D14 q3 wks x 6 (arm B); nivo 360mg iv q3wks + cape 1250mg/m2 po bid D1-D14 q3 wks x 6 (arm C). Peripheral blood mononuclear cells (PBMCs) and ctDNA were assessed at baseline (D1 of cycle 1), 6, and 12 wks and at time of recurrence, if applicable. PBMCs were stained with 30 markers and analyzed by flow cytometry to identify changes in 158 immune cell subsets at 6 wks, as a percent of total PBMCs. RaDaRTM, a deep sequencing based, tumor-informed personalized assay was utilized to detect the presence of ctDNA in plasma. Distant disease-free survival (DDFS) and overall survival (OS) were analyzed by the Kaplan-Meier method and Log-Rank test was used to compare DDFS and OS according to baseline MRD results. All pts will be followed for distant recurrence and survival for 3 yrs. Here we report the translational endpoints of the OXEL study. Clinical endpoints according to treatment received will be reported in a future analysis. Results: 45 pts were enrolled between 8/2018 and 6/2021. 29 (64%) were Caucasian and 14 (31%) were African American. Mean age at enrollment was 51 [+/- 12]. 93% of pts received a taxane-anthracycline containing neoadjuvant tx. 15 pts were randomized to each arm. DDFS probability at 1-yr and 2-yrs was 0.71 (+/- 0.07) and 0.66 (+/- 0.08) respectively. At 12 mos of median follow up, 13/45 pts (29%) experienced distant recurrence, none had local recurrence. 43 pts were evaluated for PBMC subsets. Changes in PBMC subsets at 6 wks were different amongst the arms; in arm A, reductions in NK subsets, including a 33% reduction in CD56dimCD16- cells, were observed, while in arm B, increases in naïve CD4+ T cells (+45%) and CD73+CD8+ T cells (+12%) and reductions in ki67+CD8+ T cells (-48%) were noted. In arm C, increases were observed in conventional dendritic cells (+36%), effector memory ki67+CD4+ T cells (+46%), and CD56dimCD16- NK cells (+29%). 33 pts underwent successful MRD analysis. 12/33 (36%) pts were MRD+ at baseline. 2/12 pts MRD+ at baseline subsequently cleared MRD, with undetectable ctDNA on future time points; neither patient has had recurrence to date. The remaining 10/12 MRD+ pts (83%) have experienced distance recurrence. 21/33 (64%) pts were ctDNA negative at baseline; 20/33 remained negative for all follow up timepoints. 10/11 pts experiencing distant recurrence were MRD+ at baseline, compared to 1/11 pt who became MRD+ at wk 6 post initiation of tx. At 12 mos of median follow-up, baseline MRD+ testing was significantly associated with an inferior DDFS ( p&lt;0.0001 Log-rank test, median DDFS 4.0 mos vs. not reached) and OS (p=0.02 Log-rank test, median OS not reached for both groups). Results will be updated at the time of abstract presentation. Conclusions: Changes in PBMC subsets were associated with receipt of chemo and/or immunotherapy. Our results suggest that baseline MRD+ in pts without pCR is a poor prognostic factor. Future trials aiming to optimize adjuvant treatment with chemo and/or immunotherapy in residual TNBC should consider incorporating ctDNA as a selection marker of pts at higher risk of recurrence.

Citation Format: Filipa Lynce, Candace Mainor, Xue Geng, Greg Jones, Ilana Schlam, Hongkun Wang, Ute Feger, Renee Donahue, Nicole Toney, Caroline Jochems, Jeffrey Schlom, Christopher Gallagher, Rita Nanda, Deena Graham, Erica M Stringer-Reasor, Neelima Denduluri, Julie Collins, Asma A Dilawari, Ami Chitalia, Shruti Tiwari, Raquel Nunes, Rebecca Kaltman, Katia Khoury, Margaret Gatti-Mays, Sandra M Swain, Heather A. Parsons, Paula Pohlmann, Claudine Isaacs. Peripheral immune subsets and circulating tumor DNA (ctDNA) in patients (pts) with residual triple negative breast cancer (TNBC) treated with adjuvant immunotherapy and/or chemotherapy (chemo): The OXEL study [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 PD9-02.

Hematologic safety of palbociclib in combination with endocrine therapy in patients with benign ethnic neutropenia and advanced breast cancer

BACKGROUND

Cyclin-dependent kinase 4/6 (CDK4/6) inhibitors, including palbociclib, are approved to treat hormone receptor (HR)-positive/human epidermal growth factor receptor 2 (HER2)-negative advanced breast cancer (ABC) and are associated with hematologic toxicity. African American women, who are underrepresented in CDK4/6 inhibitor clinical trials, may experience worse neutropenia because of benign ethnic neutropenia. The authors specifically investigated the hematologic safety of palbociclib in African American women with HR-positive/HER2-negative ABC.

METHODS

PALINA was a single-arm, open-label, investigator-initiated study of palbociclib (125 mg daily; 21 days on and 7 days off) plus endocrine therapy (ET) in African American women who had HR-positive/HER2-negative ABC and a baseline absolute neutrophil count ≥1000/mm³ (ClinicalTrials.gov identifier NCT02692755). The primary outcome was the proportion of patients who completed 12 months of therapy without experiencing febrile neutropenia or treatment discontinuation because of neutropenia. Single nucleotide polymorphism analysis was used to assess Duffy polymorphism status.

RESULTS

Thirty-five patients received ≥1 dose of palbociclib plus ET; 19 had a Duffy null polymorphism (cytosine/cytosine). There were no reports of febrile neutropenia or permanent study discontinuation because of neutropenia. Significantly more patients with the Duffy null versus the wild-type variant had grade 3 and 4 neutropenia (72.2% vs 23.1%; P = .029) and required a palbociclib dose reduction (55.6% vs 7.7%; P = .008). Patients with the Duffy null versus the wild-type variant had lower overall relative dose intensity (mean ± SD, 81.89% ± 15.87 and 95.67% ± 5.89, respectively; P = .0026) and a lower clinical benefit rate (66.7% and 84.6%, respectively).

CONCLUSIONS

These findings suggest that palbociclib is well tolerated in African American women with HR-positive/HER2-negative ABC. Duffy null status may affect the incidence of grade 3 neutropenia, dose intensity, and possibly clinical benefit.

Does Scalp Cooling Have the Same Efficacy in Black Patients Receiving Chemotherapy for Breast Cancer?

LESSONS LEARNED

Despite U.S. Food and Drug Administration approval to reduce alopecia, data on efficacy of scalp cooling in Black patients with cancer are limited by lack of minority representation in prior clinical trials. Scalp cooling devices may have less efficacy in Black patients; additional studies are required to explore the possible causes for this, including hair texture and cap design.

BACKGROUND

The Paxman scalp cooling (SC) device is U.S. Food and Drug Administration (FDA)-approved for prevention of chemotherapy-induced alopecia. Studies report 50%-80% success rates and high patient satisfaction, yet there have been no studies of SC in Black patients. We conducted a phase II feasibility study of Paxman SC with a planned enrollment of 30 Black patients receiving chemotherapy for stage I-III breast cancer.

METHODS

Black patients who planned to receive at least four cycles of chemotherapy with non-anthracycline (NAC) or anthracycline (AC) regimens were eligible. Alopecia was assessed by trained oncology providers using the modified Dean scale (MDS) prior to each chemotherapy session. Distress related to alopecia was measured by the Chemotherapy Alopecia Distress Scale (CADS).

RESULTS

Fifteen patients enrolled in the intervention before the study was closed early because of lack of efficacy. Median MDS and CADS increased after SC, suggesting increased hair loss (p < .001) and alopecia distress (p = .04). Only one participant was successful in preventing significant hair loss; the majority stopped SC before chemotherapy completion because of grade 3 alopecia (>50% hair loss).

CONCLUSION

SC may not be efficacious in preventing alopecia in Black women. Differences in hair thickness, hair volume, and limitations of cooling cap design are possible contributing factors.

Abstract PS9-26: Pelvic floor disorders and quality of life among breast cancer survivors

Introduction: Approximately 25% of women in the United States experience a symptomatic pelvic floor disorder such as urinary incontinence, pelvic organ prolapse, anal incontinence, and sexual dysfunction. Aspects associated with breast cancer treatment such a chemotherapy, oophorectomy/ovarian suppression, and endocrine therapy may predispose women to pelvic floor disorders. The prevalence of pelvic floor disorders among breast cancer survivors has been cited at 18%, but unpublished cross-sectional data suggests the prevalence may be much higher. In this study, 8.5% - 11.5% of participants experienced prolapse symptoms, 56.2% experienced anal incontinence symptoms, and 43.3% - 51.2% experience urinary incontinence symptoms. While pelvic floor dysfunction is associated with lower quality of life, it is unknown if breast cancer survivors with pelvic floor disorders experience decreased quality of life. The primary aim of this study was to assess if breast cancer survivors with pelvic floor disorders experience lower quality of life.

Methods: Women 18 years or older who were previously treated for breast cancer and who were enrolled in a cancer research registry were invited to complete the Pelvic Floor Distress Inventory 20 (PFDI-20), the Female Sexual Function Index (FSFI), and the Short Form 12. Demographic and clinical data were abstracted from the research registry. A participant was considered eligible for the study if she had enrolled in the cancer registry and completed all core questions (i.e. demographics, cancer diagnosis, cancer treatment, endocrine therapy, medical/surgical history, and risk factors). As per standard PFDI-20 reporting, presence of a symptom was defined as answering a 1, 2, 3, or 4 to a question, while presence of a bothersome symptom was defined as answering a 2, 3, or 4. A score of 26 or less on the FSFI was considered indicative of sexual dysfunction.

Results: A total of 634 women were considered eligible for enrollment in the study. 445 were able to be contacted, and 410 women agreed to participate in the study. Of those, 303 returned the PFDI-20 questionnaire and FSFI questionnaire, and 264 returned the SF-12 for response rates of 74% and 64%, respectively. Overall, higher scores on the PFDI-20 was associated with lower scores on both the physical and mental components of the SF-12 (Rho = -0.298, p = &lt;.0001; Rho = -0.202, p = .0009, respectively). When the PFDI-20 was broken into subscores, higher POPDI scores (prolapse) was associated with lower physical component scores but not lower mental component scores. Higher CRADI scores (anal incontinence) and UDI-6 scores (urinary incontinence) were associated with lower physical and mental scores. Neither overall FSFI scores or subset domain scores were associated with lower physical or mental component scores of the SF-12. In linear regression analysis, PFDI summary score remained statistically significantly related to both mental and physical component subscores after controlling for age, race, stage of breast cancer, time since diagnosis, and use of adjuvant endocrine therapy. FSFI scores were related to age and endocrine therapy use, but were not related to SF-12 scores.

Conclusion: Among a subset of breast cancer survivors, pelvic disorders including pelvic organ prolapse, urinary incontinence, and anal incontinence exist, and these disorders are associated with decreased mental wellbeing. All pelvic floor disorders except pelvic organ prolapse were associated with decreased physical wellbeing. None of the domains of female sexual dysfunction were associated with decreased physical or mental wellbeing among breast cancer survivors. A subset of breast cancer survivors experiences bothersome pelvic floor disorders and thus screening for these disorders can increase referrals to appropriate treatment and complement survivorship care to enhance overall quality of life.

Citation Format: Jon F Pennycuff, Felice Yang, Tania Lobo, Caroline Jackman, Colleen McGuire, Ami Chitalia, Kristi Graves. Pelvic floor disorders and quality of life among 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 PS9-26.

Scalp cooling to prevent chemotherapy induced alopecia (CIA) in black patients: Differences in efficacy?

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Background: The Paxman scalp cooling device has been used for over 20 years to prevent CIA, obtaining FDA clearance in the U.S. in 2017. Prior studies reported 50-80% success and high patient satisfaction yet included few or no black patients. In the U.S. this may reflect disparities in access due to cost, awareness, or availability. We opened a prospective observational study combining patient-reported outcomes with clinical assessments of alopecia and planned to deliver scalp cooling to 30 black patients receiving chemotherapy for breast cancer. Methods: Patients who self-identified racially as black, had a new diagnosis of stage I-III breast cancer, and planned to receive chemotherapy with taxane-containing regimens were eligible. Anthracycline (AC) and non-anthracycline (NAC) chemotherapy agents were included; costs for the intervention were covered by Paxman and internal philanthropic funding. Patients who declined scalp cooling were approached for enrollment as controls. Primary endpoints were grade of alopecia as measured by providers and patient self-report using Modified Dean Scale and Visual Analog Scale (VAS) respectively. Hair preservation was defined as <50% hair loss (<grade 2) by Dean and score < 50 on VAS. Secondary endpoints were alopecia by NCI grading scale and psychosocial from CADS and EORTC QLQ BR45 questionnaires. Results: 15 out of 30 planned participants enrolled by February 2020 with interim analysis and hold in accrual due to lack of efficacy. Four patients remain on treatment. Of 11 scalp cooling patients who completed chemotherapy, 0 prevented significant alopecia. Nine discontinued use of scalp cooling before completion (1 due to scheduling, 8 due to >grade 3 alopecia). The 2 patients who used scalp cooling for the duration had >grade 3 alopecia before the last cycle of treatment. Conclusions: Scalp cooling is an important supportive therapy that can reduce chance of alopecia, a bothersome side effect for patients. Our experience indicates decreased efficacy in black patients with both AC and NAC regimens. This is an important negative result to explore. Discussions with the Paxman team and providers with expertise in alopecia are underway to explore contributing factors such as hair thickness, prior hair treatments, and cap design. [Table: see text]

Abstract P2-13-07: A lifestyle intervention program for obese breast cancer survivors using shared appointments, technology, and community partners in an underserved area

Introduction: Obesity is associated with a 41% increase in all-cause mortality in breast cancer survivors. The majority of patients treated for breast cancer at our center are obese and most patients are racial and ethnic minority women living in low-income neighborhoods. Numerous barriers exist for weight management and physical activity interventions in this patient population. We aimed to assess the feasibility of a lifestyle intervention in 30 obese breast cancer survivors using shared medical appointments and community partnerships. Methods: 30 patients with stage I-III breast cancer with a BMI ≥30 kg/m2 treated in the preceding 5 years were enrolled through medical oncology and breast surgery clinics. All participants were given a Fitbit® to monitor physical activity and a $25 grocery gift card for a shopping trip with a nutritionist. Participants were expected to attend at least 10 group shared medical appointments (SMA) offered weekly on-site. SMA included nutrition education, cooking instruction, exercise classes or survivorship lectures. We collected participant feedback on SMA. Initial study end points were feasibility of intervention delivery measured by number of SMA appointments and physical activity (steps) measured by Fitbit®. The study was divided in three phases. Phase I/II: patients were required to have baseline evaluations, attend 10 SMA, share Fitbit® information, and complete validated eating and health questionnaires (REAP-S and SF-36, respectively) at scheduled time intervals. In phase III, we provided participants with a binder with information on low-cost fitness and nutrition options in patient’s neighborhoods and awarded prizes for high-performing participants. Results: We enrolled 30/30 participants in less than 6 months from opening; 80% were African-American. Three enrolled subjects did not complete more than one SMA. Participants attended an average of 10.2 SMA; attendance ranged from 5-10 participants per session. 63% (n=19) of participants attended the required 10 or more of the required SMA sessions (average compliance with clinic appointments is 50-60%). Participants had an average of -0.18 kg weight loss; 43% (n=13) lost weight and 40% (n=12) gained weight during the intervention (5 participants lost to follow-up or did not have weight changes during intervention). The range of weight loss was 0.1 to 7 kg and weight gain 0.2 to 6.2 kg. Twenty-four participants had consistent Fitbit® steps recorded; 19 increased their average of daily steps and 7 decreased from baseline, however, the steps varied significantly week to week. At baseline, average daily steps was 3,977 (range 200 to 18,432; SD = 4,236 steps) and 5,526 (range 728 to 14,006; SD = 2437 steps) post- intervention. The number of participants who increased steps (n=19) was significantly greater than the number of participants who decreased steps (n=7; p=0.014). The total cost of the intervention was $150 per patient. Challenges to study implementation included collection of Fitbit® data at consistent intervals and the available times for offering SMA; these times precluded enrollment and compliance for patients who work during the day. Conclusions: Our pilot study of a low-cost lifestyle intervention program appears to be feasible and beneficial for obese patients in a largely underserved community. SMA contributed to compliance and had positive feedback; patients expressed high levels of interest and engagement in the intervention. After the intervention participants were motivated to continue with lifestyle modifications and formed a Facebook® page to maintain connections. In the future, the goal is to incorporate this program as part of our survivorship care and expand it to other malignancies and potentially to other sites.

Citation Format: Ilana Schlam, Princess Alintah, Christopher Gallagher, Marc Boisvert, Ami Chitalia, Shruti Tiwari, Patrick Martone, Chiranjeev Dash, Kristi Graves, Asma Dilawari. A lifestyle intervention program for obese breast cancer survivors using shared appointments, technology, and community partners in an underserved area [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 P2-13-07.

Abstract P2-10-10: Lower pathologic complete response rate with dual-HER2 blockage and chemotherapy in African Americans and ethnic minorities

Introduction: Racial disparities in breast cancer outcomes are well documented with age-adjusted mortality among African American (AA) women 40% higher than Caucasian women. Some studies have demonstrated poor response to neoadjuvant chemotherapy in AA with triple negative breast cancer but data regarding pathologic complete response rate (pCR) in HER2 positive disease are lacking. TRYPHAENA trial demonstrated a high pCR rate after treatment with dual HER2 blockage along with chemotherapy. Due to underrepresentation of African Americans and minorities in the trials leading to the approval of dual HER2 blockage (Gianni et al; Lancet Oncology;13: 25-32) in early stage breast cancer, data is lacking on the efficacy and tolerability of this treatment in this subgroup of patients. Methods: After IRB approval, pharmacy records were utilized to identify patients treated with dual HER2 blockade in neoadjuvant setting at our institution. Individual patient charts were reviewed to identify AA patients and other ethnic minorities. We also obtained details of the patient age, clinical stage, pathological stage, ER/PR status, treatment received, side effects leading to dose reductions if any. pCR was defined as absence of invasive or noninvasive cancer in the breast and lymph nodes (ypT0N0). Results:50 patients with a median age of 53 years met our inclusion criteria. 86% patients self-reported as AA and 14% were other minorities as recorded in EMR. 90% patients were treated with Taxotere, Carboplatin, Trastuzumab and Pertuzumab (TCHP) and 10% received Adriamycin, Cyclophosphamide, Paclitaxel, Trastuzumab and Pertuzumab (AC-THP) chemotherapy. Clinical staging was: Stage I- 4 %; Stage II- 84 %, and Stage III- 12 %. 46% of patients had hormone receptor (HR) positive tumors and 54% patients were HR negative. 30% (15/50) of patients required dose reduction or omission for diarrhea, neuropathy, or cytopenia. 18%(9/50) patients had doses omitted. The overall observed pCR rate (ypT0N0) was 42%(21/50). As expected, the pCR rate was higher in patients with HR negative/HER2 positive breast cancer compared to HR positive/HER2 positive breast cancer. 44% (12/27) vs. 39% (9/23), respectively.Conclusion: Dual HER2 blockade was associated with a lower pCR rate (42%) in AA and other minorities compared to rate of 52% as reported by TRYPHAENA trial (n=77). The treatment was well tolerated but higher percent of patients required a dose reduction or omission (Tiwari et al; Breast Cancer Res Treat; 158:189-193).The most common side effects were diarrhea, neuropathy and cytopenias. Further prospective studies are needed to elucidate the role of biologic differences in chemosensitivity and balancing the variables of increased number of dose reductions and effect of socioeconomic differences in an underserved minority population.

Citation Format: Shruti R Tiwari, Prasun Mishra, Asma Dilawari, Christopher M Gallagher, Ami Chitalia, Patricia Wehner, Marc E Boisvert. Lower pathologic complete response rate with dual-HER2 blockage and chemotherapy in African Americans and ethnic minorities [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 P2-10-10.

Abstract P1-19-20: Safety of palbociclib in African American women with hormone receptor positive HER2 negative advanced breast cancer and benign ethnic neutropenia: PALINA study

Background: There are significant racial disparities in breast cancer outcomes between African American women (AAW) and Caucasian women (CW) in the US. It has been reported that AAW have more chemotherapy dose reductions than CW which results in worse clinical outcomes (Schneider BP et al. JCO Precis Oncol 2017). Given the high incidence of benign ethnic neutropenia (BEN) in AAW, we sought to evaluate the hematological safety of palbociclib in this group of patients. A polymorphism (SNP rs2814778 at chromosome 1q23.2) in the Duffy Antigen Receptor Chemokine (DARC) gene is implicated in the pathophysiology of BEN. AAW have been historically underrepresented in clinical trials including studies that led to the FDA approval of palbociclib. This diversity gap can compromise the generalizability of clinical trial results and further exacerbate minority health disparities.

Methods: PALINA is a phase II study that evaluated the hematological safety of palbociclib with endocrine therapy (ET) in 35 AAW with HR positive HER2 negative advanced breast cancer (ABC) and ANC ≥1,000 cells/mm3. Eligible patients were self-identified as African, African-American or Black, PS 0-2 and had not received a prior CDK4/6 inhibitor (CDK4/6i). Treatment included palbociclib 125mg daily for 21 days followed by 7 days off and either an aromatase inhibitor (AI) or fulvestrant per investigator discretion. Maximum time allowed on study was 12 months. Responding patients could continue palbociclib off trial. Presence of the Duffy null polymorphism as a predictive marker for neutrophil count was assessed at baseline. Metabolite and exosomal signature (proteins and RNA) of drug resistance were also evaluated at different time points and will be reported separately. Primary endpoint was the proportion of patients who completed planned oncologic therapy without the development of a hematological event defined as episodes of febrile neutropenia (FN) or treatment discontinuation due to neutropenia. A two-stage design was used to test if the completion rate of planned oncologic therapy without a hematological event was at least 80% versus if it was below 60%, with 80% power at a significance level of 5%.

Results: 35 women were enrolled from 5 different institutions. Mean age was 64 years (30-90). 9% (3/35) of patients had PS of 2. Visceral involvement was present in 51% (18/35) of patients; 60% (21/35) received an AI and 40% (14/35) received fulvestrant. Baseline median ANC was 3,100 (1,300-11,100) cells/mm3. None of the patients had FN or required discontinuation of therapy due to neutropenia. Grade 3 and 4 neutropenia were experienced by 46% (16/35) and 3% (1/35) of patients respectively. Dose delays occurred in 17 patients, and 13 patients required dose reduction (5 to 100mg and 8 to 75 mg). Clinical benefit rate (CR+PR+SD persisting for ≥6 months) was 70%. Of the 29 patients who have completed study participation, the median time on treatment was 280 days (14, 385) and 15 continued on commercial palbociclib. Last visit on study estimated for 10/2019. The Duffy polymorphism was evaluated in 94% (33/35) of patients. The Duffy null phenotype was present in 58% (19/33) of the patients. Lower baseline ANC (2,400 vs 4,300 cells/mm3, p0.006), grade 3 neutropenia (63.2 vs 21.4%, p0.003) and dose reductions (52.6 vs 7.1%, p0.009) were more common in patients with the Duffy null polymorphism.

Conclusion: This is the first trial specifically designed to evaluate the hematologic toxicity of a CDK4/6i in AAW. Although patients with the Duffy null phenotype had more dose reductions and treatment delays due to neutropenia, this did not result in episodes of FN or treatment discontinuation due to neutropenia. This analysis suggests that palbociclib with ET is safe in AAW including those with the Duffy null phenotype.

Citation Format: Filipa Lynce, Rebecca Zhuo, Matthew Blackburn, Christopher Gallagher, Olwen Hahn, Maysa Abu-Khalaf, Mahsa Mohebtash, Tianmin Wu, Paula Pohlmann, Asma Dilawari, Shruti Tiwari, Ami Chitalia, Robert Warren, Ming Tan, Ayesha Shajahan-Haq, Claudine Isaacs. Safety of palbociclib in African American women with hormone receptor positive HER2 negative advanced breast cancer and benign ethnic neutropenia: PALINA study [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 P1-19-20.

Descriptive analysis of genetic aberrations and cell of origin in Richter transformation

Richter transformation (RT) is a progression from chronic lymphocytic leukemia (CLL) to a more aggressive lymphoma, most often diffuse large B-cell lymphoma (DLBCL). Due to the rarity of the disease, data regarding the molecular profile and cell of origin (COO) of RT is limited. We performed immunohistochemistry analysis for COO determination and next-generation sequencing for gene mutation analysis in 11 RT patients. Seventy-nine percent of our patients were classified as non-GCB phenotype. Of the 57 unique mutations identified, the three most commonly mutated genes were TP53, TET2, and CREBBP. Neither TET2 nor CREBBP has been previously described in RT. Our analysis provides additional information to help guide further investigation of both the diagnosis and treatment of this complex and heterogeneous disease.

Evaluating radiotherapy options in breast cancer: does intraoperative radiotherapy represent the most cost-efficacious option?

INTRODUCTION

This study analyzed the cost-efficacy of intraoperative radiation therapy (IORT) compared with whole-breast irradiation (WBI) and accelerated partial-breast irradiation (APBI) for early-stage breast cancer.

MATERIALS AND METHODS

Data for this analysis came from 2 phase III trials: the TARGIT (Targeted Intraoperative Radiotherapy) trial and the ELIOT (Electron Intraoperative Radiotherapy) trial. Cost analyses included a cost-minimization analysis and an incremental cost-effectiveness ratio analysis including a quality-adjusted life-year (QALY) analysis. Cost analyses were performed comparing IORT with WBI delivered using 3-dimensional conformal radiotherapy (3D-CRT), APBI 3D-CRT, APBI delivered with intensity-modulated radiotherapy (IMRT), APBI single-lumen (SL), APBI multilumen (ML), and APBI interstitial (I).

RESULTS

Per 1000 patients treated, the cost savings with IORT were $3.6-$4.3 million, $1.6-$2.4 million, $3.6-$4.4 million, $7.5-$8.2 million, and $2.8-$3.6 million compared with WBI 3D-CRT, APBI IMRT, APBI SL, APBI ML, and APBI I, respectively, with a cost decrement of $1.6-$2.4 million compared with APBI 3D-CRT based on data from the TARGIT trial. The costs per QALY for WBI 3D-CRT, APBI IMRT, APBI SL, APBI ML, and APBI I compared with IORT were $47,990-$60,002; $17,335-$29,347; $49,019-$61,031; $108,162-$120,173; and $36,129-$48,141, respectively, based on data from the ELIOT trial. These results are consistent with APBI and WBI being cost-effective compared with IORT.

CONCLUSION

Based on cost-minimization analyses, IORT represents a potential cost savings in the management of early-stage breast cancer. However, absolute reimbursement is misleading, because when additional medical and nonmedical costs associated with IORT are factored in, WBI and APBI represent cost-effective modalities based on cost-per-QALY analyses. They remain the standard of care.