Adjuvant platinum versus capecitabine for residual, invasive, triple-negative breast cancer: Patient-reported outcomes in ECOG-ACRIN EA1131

BACKGROUND

Patient-reported outcomes (PROs) are a better tool for evaluating the experiences of patients who have symptomatic, treatment-associated adverse events (AEs) compared with clinician-rated AEs. The authors present PROs assessing health-related quality of life (HRQoL) and treatment-related neurotoxicity for adjuvant capecitabine versus platinum on the Eastern Cooperative Oncology Group-American College of Radiology Imaging Network (ECOG-ACRIN) EA1131 trial (ClinicalTrials.gov identifier NCT02445391).

METHODS

Participants completed the National Comprehensive Cancer Network Functional Assessment of Cancer Therapy-Breast Cancer Symptom Index (NFBSI-16) and the Functional Assessment of Cancer Therapy-Gynecologic Oncology Group neurotoxicity subscale (platinum arm only) at baseline, cycle 3 day 1 (C3D1), 6 months, and 15 months. Because of early termination, power was insufficient to test the hypothesis that HRQoL, as assessed by the NFBSI-16 treatment side-effect (TSE) subscale, would be better at 6 and 15 months in the capecitabine arm; all analyses were exploratory. Means were compared by using t-tests or the Wilcoxon rank-sum test, and proportions were compared by using the χ2 test.

RESULTS

Two hundred ninety-six of 330 eligible patients provided PROs. The mean NFBSI-16 TSE subscale score was lower for the platinum arm at baseline (p = .02; absolute difference, 0.6 points) and for the capecitabine arm at C3D1 (p = .04; absolute difference, 0.5 points), but it did not differ at other times. The mean change in TSE subscale scores differed between the arms from baseline to C3D1 (platinum arm, 0.15; capecitabine arm, -0.72; p = .03), but not from baseline to later time points. The mean decline in Functional Assessment of Cancer Therapy-Gynecologic Oncology Group neurotoxicity subscale scores exceeded the minimal meaningful change (1.38 points) from baseline to each subsequent time point (all p < .05).

CONCLUSIONS

Despite the similar frequency of clinician-rated AEs, PROs identified greater on-treatment symptom burden with capecitabine and complemented clinician-rated AEs by characterizing patients' experiences during chemotherapy.

Disease-free survival as a surrogate for overall survival in HR+/HER2- early breast cancer: A correlation analysis

BACKGROUND

Overall survival (OS) is a universally accepted measure of clinical benefit; however, prolonged follow-up is needed to observe sufficient events. Disease-free survival (DFS) has been widely adopted as a primary endpoint for early breast cancer (EBC) trials, as follow-up is comparatively shorter. Here, we present an analysis evaluating DFS as a surrogate for OS for adjuvant treatment of hormone receptor-positive/human epidermal growth factor receptor 2-negative (HR+/HER2-) EBC.

METHODS

A systematic literature review which included randomized controlled trials (RCTs) with ≥80% of adult patients with HR+/HER2- EBC was conducted. The RCTs evaluated various systemic therapeutic categories; key inclusion criteria included reporting of DFS and OS hazard ratios (HRs) and mature OS data. Spearman rank correlation and weighted linear regression analyses evaluated DFS and OS HR correlation. A scenario analysis tested base-case analysis robustness, and a parallel analysis using patient-level data was conducted.

RESULTS

The base case (N = 14 RCTs) showed an unweighted Spearman coefficient of 0.81 between OS and DFS (weighted: 0.81), with 84% of the variability in OS explained by DFS differences (R2 from weighted regression). The surrogate threshold effect (Burzykowski T, Buyse M. Pharm Stat. 2006;5:173-186) was 0.82 for DFS/OS HR. Scenario analysis (n = 9 RCTs), which excluded chemotherapy trials, and patient-level analysis using FACE trial data were consistent with the base-case analysis.

CONCLUSIONS

These analyses support DFS as a reliable surrogate endpoint for OS in adjuvant HR+/HER2- EBC trials. Using DFS as a surrogate measure will permit timelier access to novel treatments for patients with HR+/HER2- EBC.

Racial disparities in outcomes of patients with stage I-III triple-negative breast cancer after adjuvant chemotherapy: a post-hoc analysis of the E5103 randomized trial

PURPOSE

Breast cancer mortality is higher in Black women than other racial groups. This difference has been partially attributed to a higher proportion of triple-negative breast cancer (TNBC). However, it is uncertain if survival disparities exist in racially diverse TNBC patients receiving similar treatments. Here, we examine racial differences in disease-related outcomes in TNBC patients treated on the E5103 clinical trial.

METHODS

From 2007 to 2011, 4,994 patients with stage I-III HER2-negative breast cancer were randomized to adjuvant chemotherapy with or without bevacizumab. This analysis was limited to the subset of 1,742 TNBC patients with known self-reported race. Unadjusted Kaplan-Meier curves and adjusted Cox-Proportional Hazards models were used to determine breast cancer events and survival outcomes.

RESULTS

Of the analysis population, 51 (2.9%) were Asian, 269 (15.4%) Black, and 1422 (81.6%) White. Median age was 51 years. Patient characteristics, treatment arm, and local therapies were similar across racial groups. White women were more commonly node-negative (56% vs. 49% and 44% in Asian and Black women, respectively; p < 0.01). At a median follow-up of 46 months, unadjusted Kaplan-Meier locoregional and distant recurrence, and disease-free and overall survival, did not differ significantly by race. In Cox models adjusted for patient and tumor characteristics and treatment arm, race was not associated with any disease event. Larger tumor size and nodal involvement were consistently associated with breast cancer events.

CONCLUSION

This clinical trial population of similarly treated TNBC patients showed no racial differences in breast cancer outcomes. Disease extent, rather than race, was associated with disease events.

PACE: A Randomized Phase II Study of Fulvestrant, Palbociclib, and Avelumab After Progression on Cyclin-Dependent Kinase 4/6 Inhibitor and Aromatase Inhibitor for Hormone Receptor-Positive/Human Epidermal Growth Factor Receptor-Negative Metastatic Breast Cancer

PURPOSE

Cyclin-dependent kinase (CDK) 4/6 inhibitors (CDK4/6is) are an important component of treatment for hormone receptor-positive/human epidermal growth factor receptor 2-negative (HER2-) metastatic breast cancer (MBC), but it is not known if patients might derive benefit from continuation of CDK4/6i with endocrine therapy beyond initial tumor progression or if the addition of checkpoint inhibitor therapy has value in this setting.

METHODS

The randomized multicenter phase II PACE trial enrolled patients with hormone receptor-positive/HER2- MBC whose disease had progressed on previous CDK4/6i and aromatase inhibitor (AI) therapy. Patients were randomly assigned 1:2:1 to receive fulvestrant (F), fulvestrant plus palbociclib (F + P), or fulvestrant plus palbociclib and avelumab (F + P + A). The primary end point was investigator-assessed progression-free survival (PFS) in patients treated with F versus F + P.

RESULTS

Overall, 220 patients were randomly assigned between September 2017 and February 2022. The median age was 57 years (range, 25-83 years). Most patients were postmenopausal (80.9%), and 40% were originally diagnosed with de novo MBC. Palbociclib was the most common previous CDK4/6i (90.9%). The median PFS was 4.8 months on F and 4.6 months on F + P (hazard ratio [HR], 1.11 [90% CI, 0.79 to 1.55]; P = .62). The median PFS on F + P + A was 8.1 months (HR v F, 0.75 [90% CI, 0.50 to 1.12]; P = .23). The difference in PFS with F + P and F + P + A versus F was greater among patients with baseline ESR1 and PIK3CA alterations.

CONCLUSION

The addition of palbociclib to fulvestrant did not improve PFS versus fulvestrant alone among patients with hormone receptor-positive/HER2- MBC whose disease had progressed on a previous CDK4/6i plus AI. The increased PFS seen with the addition of avelumab warrants further investigation in this patient population.

Taxanes for the treatment of breast cancer during pregnancy: an international cohort study

INTRODUCTION

The addition of taxanes to anthracycline-based chemotherapy is considered standard of care in the treatment of breast cancer. However, there are insufficient data regarding the safety of taxanes during pregnancy. The aim of this study was to describe the incidence of obstetric and neonatal adverse events associated with the use of taxane-containing chemotherapy regimens for the treatment of breast cancer during pregnancy.

METHODS

This is a multicenter, international cohort study of breast cancer patients treated with taxanes during pregnancy. A descriptive analysis was undertaken to synthetize available data.

RESULTS

A total of 103 patients were included, most of whom were treated with paclitaxel and anthracyclines given in sequence during gestation (90.1%). The median gestational age at taxane initiation was 28 weeks (range = 12-37 weeks). Grade 3-4 adverse events were reported in 7 of 103 (6.8%) patients. The most common reported obstetric complications were intrauterine growth restriction (n = 8 of 94, 8.5%) and preterm premature rupture of membranes (n = 5 of 94, 5.3%). The live birth rate was 92 of 94 (97.9%), and the median gestational age at delivery was 37 weeks (range = 32-40 weeks). Admission to an intensive care unit was reported in 14 of 88 (15.9%) neonates, and 17 of 70 (24.3%) live births resulted in small for gestational age neonates. Congenital malformations were reported in 2 of 93 (2.2%).

CONCLUSION

Obstetric and neonatal outcomes after taxane exposure during pregnancy were generally favorable and did not seem to differ from those reported in the literature with standard anthracycline-based regimens. This study supports the use of taxanes during gestation when clinically indicated.

Association of N-terminal Pro-Brain natriuretic peptide with survival among US cancer survivors

BACKGROUND

N-terminal pro-brain natriuretic peptide (NT-proBNP) is a cardiac biomarker associated with the risk of heart failure and death in the general population but has not been explored in cancer survivors.

METHODS

Using a US nationally representative sample of adults ≥20 years from the National Health and Nutrition Examination Survey from 1999 to 2004, this study compared NT-proBNP levels between non-cancer adults (n = 12574) and cancer survivors (n = 787) and examined the association of NT-proBNP with all-cause and cause-specific mortality among cancer survivors.

RESULTS

Cancer survivors had higher NT-proBNP levels than non-cancer adults (median: 125.4 [IQR, 52.4 to 286.0] vs 43.2 [IQR, 20.3-95.0]). In particular, survivors of breast, prostate, and colorectal cancers had higher NT-proBNP levels than non-cancer adults (multivariable-adjusted P<.05). 471 survivors died (cancer: 141; cardiac disease: 95) during a median follow-up of 13.4 years (9,393 person-years). Among cancer survivors, higher NT-proBNP levels were statistically associated with increased risks of all-cause (HR, 1.31 [95% CI, 1.18-1.46]) and cardiac (HR, 1.55 [95% CI, 1.21-2.00) mortality but not with death due to cancer (HR, 1.10 [95% CI, 0.92-1.32]). Higher NT-proBNP levels were associated with elevated overall mortality in survivors of prostate (HR, 1.45 [95% CI, 1.17-1.79]) and colorectal (HR, 1.78 [95% 1.12-2.85]) cancers (P-interaction = 0.169). Non-linear dose-response relationships were observed between NT-proBNP and mortality, with statistically significant relationships emerging above 125 pg/ml.

CONCLUSIONS

Cancer survivors had higher NT-proBNP than non-cancer adults, and elevated NT-proBNP levels were associated with higher risks of all-cause and cardiac mortality in cancer survivors.

A randomized phase II study of metronomic cyclophosphamide and methotrexate (CM) with or without bevacizumab in patients with advanced breast cancer

PURPOSE

Metronomic chemotherapy has the potential to offer tumor control with reduced toxicity when compared to standard dose chemotherapy in patients with metastatic breast cancer. As metronomic chemotherapy may target the tumor microvasculature, it has the potential for synergistic effects with antiangiogenic agents such as the VEGF-A inhibitor bevacizumab.

METHODS

In this randomized phase II study, patients with metastatic breast cancer were randomized to receive metronomic oral cyclophosphamide and methotrexate (CM) combined with bevacizumab (Arm A) or CM alone (Arm B). The primary endpoint was objective response rate (ORR). Secondary endpoints included progression-free survival (PFS), overall survival (OS), and safety and tolerability.

RESULTS

A total of 55 patients were enrolled, with 34 patients treated on Arm A and 21 patients treated on Arm B. The ORR was modestly higher in Arm A (26%) than in Arm B (10%); neither met the 40% cutoff for further clinical evaluation. The median time to progression (TTP) was 5.52 months (3.22-13.6) on Arm A and 1.82 months (1.54-6.70) on Arm B (log-rank p = 0.008). The median OS was 29.6 months (17.2-NA) on Arm A and 16.2 months (15.7-NA) on Arm B (log-rank p = 0.7). Common all-grade adverse events in both arms included nausea, fatigue, and elevated AST.

CONCLUSION

The combination of metronomic CM with bevacizumab significantly improved PFS over CM alone, although there was no significant difference in OS. Oral metronomic chemotherapy alone has limited activity in advanced breast cancer.

CLINICALTRIALS

gov Identifier: NCT00083031. Date of Registration: May 17, 2004.

Racial Disparities in Locoregional Recurrence in Postmenopausal Patients with Stage I-III, Hormone Receptor-Positive Breast Cancer Enrolled in the NSABP B-42 Clinical Trial

BACKGROUND

There are limited data examining racial disparities in locoregional recurrence (LRR) among women with access to high-quality care. We aimed to examine differences in late LRR by race in patients with stage I-IIIA, hormone receptor-positive (HR+) breast cancer enrolled in the National Surgical Adjuvant Breast and Bowel (NSABP) B-42 trial.

METHODS

From 2006 to 2010, 3966 postmenopausal women with stage I-IIIA HR+ breast cancer who were disease-free after 5 years of endocrine therapy were randomized to an additional 5 years of endocrine therapy or placebo. Patients were excluded if multi-racial or if race was unknown. Kaplan-Meier curves were used to estimate 6-year LRR from the time of trial registration and according to race. Cox proportional hazards models were used for adjusted survival analyses.

RESULTS

Overall, 3929 NSABP B-42 patients were included: 3688 (93.9%) White, 151 (3.8%) Black, and 90 (2.3%) Asian patients. Median follow-up was 75.2 months. Overall estimated 6-year LRR from trial registration was 1.8% and differed by race: LRR rates were 1.7% in White women, 4.9% in Black women, and 0% in Asian women (p = 0.046). Adjusted Cox proportional hazards analysis found Black race to be independently associated with LRR (hazard ratio [HzR] 2.36, 95% confidence interval [CI] 1.01-5.49; p = 0.047). Node-positivity was also associated with increased LRR (HzR 1.75, 95% CI 1.07-2.86; p = 0.025). Adjusted Cox analysis found LRR (HzR 2.32, 95% CI 1.33-4.06; p = 0.003) to be associated with increased overall mortality; however, race was not independently associated with mortality.

CONCLUSION

Among postmenopausal patients with stage I-IIIA HR+ breast cancer in the NSABP B-42 trial, racial differences in late LRR were present, with the highest LRR in Black women.

Racial and Ethnic Disparities in Outcomes After Breast-Conserving Therapy and Endocrine Therapy for DCIS: A Post-Hoc Analysis of the NSABP B-35 Randomized Clinical Trial

BACKGROUND

Racial and ethnic disparities in outcomes after treatment for ductal carcinoma in situ (DCIS) are largely unknown. The objective of this study was to examine breast cancer outcomes by race and ethnicity in the National Surgical Adjuvant Breast and Bowel Project (NSABP) B-35 clinical trial.

PATIENTS AND METHODS

The NSABP B-35 trial randomized postmenopausal women with hormone receptor-positive DCIS treated with breast-conserving therapy to 5 years of tamoxifen or anastrozole. In total, 3104 women were enrolled between 2003 and 2006. For this analysis, patients without complete self-reported race and ethnicity or with immediate trial dropout were excluded. Kaplan-Meier curves and adjusted Cox-proportional hazards models were used for analyses.

RESULTS

Of the 3061 women included, 2614 (85.4%) were non-Hispanic white (NHW), 255 (8.3%) were non-Hispanic Black (NHB), 95 (3.1%) were Hispanic, and 96 (3.1%) were Asian or Pacific Islander (API). Endocrine therapy assignment and duration were well balanced between racial and ethnic groups. Median follow-up was 9 years; unadjusted Kaplan-Meier curves did not show any racial differences in disease events. Adjusted Cox-proportional hazards models found API (versus NHW) race to be associated with higher local recurrence [hazard ratio (HzR) 2.45, p = 0.035] and NHB race to be associated with higher distant recurrence (HzR 5.03, p = 0.020) and breast cancer mortality (HzR 3.83, p = 0.046).

CONCLUSIONS

Despite similar locoregional treatments and standard endocrine therapy in a clinical trial population, racial and ethnic disparities exist in long-term outcomes for hormone-receptor-positive DCIS. These findings suggest that factors outside of access and treatment may impact DCIS outcomes by race and ethnicity.

Impact of BMI in Patients With Early Hormone Receptor-Positive Breast Cancer Receiving Endocrine Therapy With or Without Palbociclib in the PALLAS Trial

PURPOSE

BMI affects breast cancer risk and prognosis. In contrast to cytotoxic chemotherapy, CDK4/6 inhibitors are given at a fixed dose, irrespective of BMI or weight. This preplanned analysis of the global randomized PALLAS trial investigates the impact of BMI on the side-effect profile, treatment adherence, and efficacy of palbociclib.

METHODS

Patients were categorized at baseline according to WHO BMI categories. Neutropenia rates were assessed with univariable and multivariable logistic regression. Time to early discontinuation of palbociclib was analyzed with Fine and Gray competing risk models. Unstratified Cox models were used to investigate the association between BMI category and time to invasive disease-free survival (iDFS). 95% CIs were derived.

RESULTS

Of 5,698 patients included in this analysis, 68 (1.2%) were underweight, 2,082 (36.5%) normal weight, 1,818 (31.9%) overweight, and 1,730 (30.4%) obese at baseline. In the palbociclib arm, higher BMI was associated with a significant decrease in neutropenia (unadjusted odds ratio for 1-unit change, 0.93; 95% CI, 0.91 to 0.94; adjusted for age, race ethnicity, region, chemotherapy use, and Eastern Cooperative Oncology Group at baseline, 0.93; 95% CI, 0.92 to 0.95). This translated into a significant decrease in treatment discontinuation rate with higher BMI (adjusted hazard ratio [HR] for 10-unit change, 0.75; 95% CI, 0.67 to 0.83). There was no significant improvement in iDFS with the addition of palbociclib to ET in any weight category (normal weight HR, 0.84; 95% CI, 0.63 to 1.12; overweight HR, 1.10; 95% CI, 0.82 to 1.49; and obese HR, 0.95; 95% CI, 0.69 to 1.30) in this analysis early in follow-up (31 months).

CONCLUSION

This preplanned analysis of the PALLAS trial demonstrates a significant impact of BMI on side effects, dose reductions, early treatment discontinuation, and relative dose intensity. Additional long-term follow-up will further evaluate whether BMI ultimately affects outcome.

Identifying homologous recombination deficiency in breast cancer: genomic instability score distributions differ among breast cancer subtypes

PURPOSE

A 3-biomarker homologous recombination deficiency (HRD) score is a key component of a currently FDA-approved companion diagnostic assay to identify HRD in patients with ovarian cancer using a threshold score of ≥ 42, though recent studies have explored the utility of a lower threshold (GIS ≥ 33). The present study evaluated whether the ovarian cancer thresholds may also be appropriate for major breast cancer subtypes by comparing the genomic instability score (GIS) distributions of BRCA1/2-deficient estrogen receptor-positive breast cancer (ER + BC) and triple-negative breast cancer (TNBC) to the GIS distribution of BRCA1/2-deficient ovarian cancer.

METHODS

Ovarian cancer and breast cancer (ER + BC and TNBC) tumors from ten study cohorts were sequenced to identify pathogenic BRCA1/2 mutations, and GIS was calculated using a previously described algorithm. Pathologic complete response (pCR) to platinum therapy was evaluated in a subset of TNBC samples. For TNBC, a threshold was set and threshold validity was assessed relative to clinical outcomes.

RESULTS

A total of 560 ovarian cancer, 805 ER + BC, and 443 TNBC tumors were included. Compared to ovarian cancer, the GIS distribution of BRCA1/2-deficient samples was shifted lower for ER + BC (p = 0.015), but not TNBC (p = 0.35). In the subset of TNBC samples, univariable logistic regression models revealed that GIS status using thresholds of ≥ 42 and ≥ 33 were significant predictors of response to platinum therapy.

CONCLUSIONS

This study demonstrated that the GIS thresholds used for ovarian cancer may also be appropriate for TNBC, but not ER + BC. GIS thresholds in TNBC were validated using clinical response data to platinum therapy.

Circulating tumor DNA association with residual cancer burden after neoadjuvant chemotherapy in triple-negative breast cancer in TBCRC 030

BACKGROUND

We aimed to examine circulating tumor DNA (ctDNA) and its association with residual cancer burden (RCB) using an ultrasensitive assay in patients with triple-negative breast cancer (TNBC) receiving neoadjuvant chemotherapy.

PATIENTS AND METHODS

We identified responders (RCB 0/1) and matched non-responders (RCB 2/3) from the phase II TBCRC 030 prospective study of neoadjuvant paclitaxel versus cisplatin in TNBC. We collected plasma samples at baseline, 3 weeks and 12 weeks (end of therapy). We created personalized ctDNA assays utilizing MAESTRO mutation enrichment sequencing. We explored associations between ctDNA and RCB status and disease recurrence.

RESULTS

Of 139 patients, 68 had complete samples and no additional neoadjuvant chemotherapy. Twenty-two were responders and 19 of those had sufficient tissue for whole-genome sequencing. We identified an additional 19 non-responders for a matched case-control analysis of 38 patients using a MAESTRO ctDNA assay tracking 319-1000 variants (median 1000 variants) to 114 plasma samples from 3 timepoints. Overall, ctDNA positivity was 100% at baseline, 79% at week 3 and 55% at week 12. Median tumor fraction (TFx) was 3.7 × 10-4 (range 7.9 × 10-7-4.9 × 10-1). TFx decreased 285-fold from baseline to week 3 in responders and 24-fold in non-responders. Week 12 ctDNA clearance correlated with RCB: clearance was observed in 10 of 11 patients with RCB 0, 3 of 8 with RCB 1, 4 of 15 with RCB 2 and 0 of 4 with RCB 3. Among six patients with known recurrence, five had persistent ctDNA at week 12.

CONCLUSIONS

Neoadjuvant chemotherapy for TNBC reduced ctDNA TFx by 285-fold in responders and 24-fold in non-responders. In 58% (22/38) of patients, ctDNA TFx dropped below the detection level of a commercially available test, emphasizing the need for sensitive tests. Additional studies will determine whether ctDNA-guided approaches can improve outcomes.

Clonal hematopoiesis in older patients with breast cancer receiving chemotherapy

BACKGROUND

The expansion of hematopoietic stem cells carrying recurrent somatic mutations, termed clonal hematopoiesis (CH), is common in elderly individuals and is associated with increased risk of myeloid malignancy and all-cause mortality. Though chemotherapy is a known risk factor for developing CH, how myelosuppressive therapies affect the short-term dynamics of CH remains incompletely understood. Most studies have been limited by retrospective design, heterogeneous patient populations, varied techniques to identifying CH, and analysis of single timepoints.

METHODS

We examined serial samples from 40 older women with triple-negative or hormone receptor-positive breast cancer treated on the prospective ADjuVANt Chemotherapy in the Elderly trial to evaluate the prevalence and dynamics of CH at baseline and throughout chemotherapy (6 and 12 weeks).

RESULTS

CH was detected in 44% of patients at baseline and in 53% at any timepoint. Baseline patient characteristics were not associated with CH. Over the course of treatment, mutations exhibited a variety of dynamics, including emergence, expansion, contraction, and disappearance. All mutations in TP53 (n = 3) and PPM1D (n = 4), genes that regulate the DNA damage response, either became detectable or expanded over the course of treatment. Neutropenia was more common in patients with CH, particularly when the mutations became detectable during treatment, and CH was significantly associated with cyclophosphamide dose reductions and holds (P = .02).

CONCLUSIONS

Our study shows that CH is common, dynamic, and of potential clinical significance in this population. Our results should stimulate larger efforts to understand the biological and clinical importance of CH in solid tumor malignancies.

TRIAL REGISTRATION

ClinicalTrials.gov (https://clinicaltrials.gov/ct2/show/NCT03858322). Clinical trial registration number: NCT03858322.

Evaluation of Alisertib Alone or Combined With Fulvestrant in Patients With Endocrine-Resistant Advanced Breast Cancer: The Phase 2 TBCRC041 Randomized Clinical Trial

Importance

Aurora A kinase (AURKA) activation, related in part to AURKA amplification and variants, is associated with downregulation of estrogen receptor (ER) α expression, endocrine resistance, and implicated in cyclin-dependent kinase 4/6 inhibitor (CDK 4/6i) resistance. Alisertib, a selective AURKA inhibitor, upregulates ERα and restores endocrine sensitivity in preclinical metastatic breast cancer (MBC) models. The safety and preliminary efficacy of alisertib was demonstrated in early-phase trials; however, its activity in CDK 4/6i-resistant MBC is unknown.

Objective

To assess the effect of adding fulvestrant to alisertib on objective tumor response rates (ORRs) in endocrine-resistant MBC.

Design, Setting, and Participants

This phase 2 randomized clinical trial was conducted through the Translational Breast Cancer Research Consortium, which enrolled participants from July 2017 to November 2019. Postmenopausal women with endocrine-resistant, ERBB2 (formerly HER2)-negative MBC who were previously treated with fulvestrant were eligible. Stratification factors included prior treatment with CDK 4/6i, baseline metastatic tumor ERα level measurement (<10%, ≥10%), and primary or secondary endocrine resistance. Among 114 preregistered patients, 96 (84.2%) registered and 91 (79.8%) were evaluable for the primary end point. Data analysis began after January 10, 2022.

Interventions

Alisertib, 50 mg, oral, daily on days 1 to 3, 8 to 10, and 15 to 17 of a 28-day cycle (arm 1) or alisertib same dose/schedule with standard-dose fulvestrant (arm 2).

Main Outcomes and Measures

Improvement in ORR in arm 2 of at least 20% greater than arm 1 when the expected ORR for arm 1 was 20%.

Results

All 91 evaluable patients (mean [SD] age, 58.5 [11.3] years; 1 American Indian/Alaskan Native [1.1%], 2 Asian [2.2%], 6 Black/African American [6.6%], 5 Hispanic [5.5%], and 79 [86.8%] White individuals; arm 1, 46 [50.5%]; arm 2, 45 [49.5%]) had received prior treatment with CDK 4/6i. The ORR was 19.6%; (90% CI, 10.6%-31.7%) for arm 1 and 20.0% (90% CI, 10.9%-32.3%) for arm 2. In arm 1, the 24-week clinical benefit rate and median progression-free survival time were 41.3% (90% CI, 29.0%-54.5%) and 5.6 months (95% CI, 3.9-10.0), respectively, and in arm 2 they were 28.9% (90% CI, 18.0%-42.0%) and 5.4 months (95% CI, 3.9-7.8), respectively. The most common grade 3 or higher adverse events attributed to alisertib were neutropenia (41.8%) and anemia (13.2%). Reasons for discontinuing treatment were disease progression (arm 1, 38 [82.6%]; arm 2, 31 [68.9%]) and toxic effects or refusal (arm 1, 5 [10.9%]; arm 2, 12 [26.7%]).

Conclusions and Relevance

This randomized clinical trial found that adding fulvestrant to treatment with alisertib did not increase ORR or PFS; however, promising clinical activity was observed with alisertib monotherapy among patients with endocrine-resistant and CDK 4/6i-resistant MBC. The overall safety profile was tolerable.

Trial Registration

ClinicalTrials.gov Identifier: NCT02860000.

Racial and Ethnic Disparities in Locoregional Recurrence Among Patients With Hormone Receptor-Positive, Node-Negative Breast Cancer: A Post Hoc Analysis of the TAILORx Randomized Clinical Trial

Importance

Whether racial and ethnic disparities in locoregional recurrence (LRR) exist among patients with similar access to care treated in randomized clinical trials is unknown.

Objective

To examine racial and ethnic differences in LRR among patients with hormone receptor (HR)-positive, human epidermal growth factor receptor 2 (ERBB2 [formerly HER2 or HER2/neu])-negative, node-negative breast cancer enrolled in the Trial Assigning Individualized Options for Treatment (TAILORx).

Design, Setting, and Participants

This unplanned retrospective post hoc analysis examined a prospective multicenter clinical trial population of women with breast cancer enrolled between 2006 and 2010, with 9 years of follow-up. The TAILORx investigators randomized patients to treatment based on their Oncotype DX recurrence score, including endocrine therapy alone (recurrence score <11), endocrine therapy alone vs chemotherapy followed by endocrine therapy (recurrence score 11-25), or chemotherapy followed by endocrine therapy (recurrence score >25). Patients with unknown race and ethnicity or lack of follow-up were excluded from this analysis. Data analysis was performed between December 2021 and March 2022.

Main Outcome and Measures

Locoregional recurrence was defined as ipsilateral in breast, skin, chest wall, or regional nodal recurrence without concurrent distant recurrence, and was stratified by racial and ethnic group. Unadjusted Kaplan-Meier and adjusted Cox proportional hazards regression models were used for survival analyses.

Results

Of the 10 273 women enrolled in TAILORx, this analysis included 9369 with T1-2N0 HR-positive, ERBB2-negative breast cancer. Of these patients, 428 (4.6%) were Asian, 886 (9.4%) were Hispanic, 676 (7.2%) were non-Hispanic Black (hereinafter Black), and 7406 (78.8%) were non-Hispanic White (hereinafter White). Assigned treatment receipt was high, with a 9.3% (n = 870) crossover of treatment groups and a median endocrine therapy duration of longer than 60 months, ranging from 61.1 to 65.9 months, across racial and ethnic groups. A total of 6818 patients (72.6%) received radiation (6474 [96.1%] after breast-conserving surgery and 344 [13.0%] after mastectomy). At a median follow-up of 94.8 months (range, 1-138 months), 8-year LRR rates were 3.6% (95% CI, 1.6%-5.6%) in Asian patients, 3.9% (95% CI, 2.2%-5.4%) in Black patients, 3.1% in Hispanic patients (95% CI, 1.7%-4.5%), and 1.8% (95% CI, 1.5%-2.3%) in White patients (P < .001). In survival analyses adjusted for patient, tumor, and treatment factors, Asian race (hazard ratio, 1.91 [95% CI, 1.12-3.29]) and Black race (1.78 [1.15-2.77]) were independently associated with LRR. In adjusted survival analyses for breast cancer mortality, LRR was independently associated with increased breast cancer mortality (hazard ratio, 5.71 [95% CI, 3.50-9.31]).

Conclusions and Relevance

In this post hoc analysis, racial and ethnic differences in LRR were observed among patients with T1-2N0 HR-positive, ERBB2-negative breast cancer despite high rates of treatment receipt in this clinical trial population, with the highest LRR rates in Asian and Black patients. Further study is needed to understand whether failure to rescue after LRR may contribute to racial disparities in breast cancer mortality.

Trial Registration

ClinicalTrials.gov Identifier: NCT00310180.

Single duplex DNA sequencing with CODEC detects mutations with high sensitivity

Detecting mutations from single DNA molecules is crucial in many fields but challenging. Next-generation sequencing (NGS) affords tremendous throughput but cannot directly sequence double-stranded DNA molecules ('single duplexes') to discern the true mutations on both strands. Here we present Concatenating Original Duplex for Error Correction (CODEC), which confers single duplex resolution to NGS. CODEC affords 1,000-fold higher accuracy than NGS, using up to 100-fold fewer reads than duplex sequencing. CODEC revealed mutation frequencies of 2.72 × 10-8 in sperm of a 39-year-old individual, and somatic mutations acquired with age in blood cells. CODEC detected genome-wide, clonal hematopoiesis mutations from single DNA molecules, single mutated duplexes from tumor genomes and liquid biopsies, microsatellite instability with 10-fold greater sensitivity and mutational signatures, and specific tumor mutations with up to 100-fold fewer reads. CODEC enables more precise genetic testing and reveals biologically significant mutations, which are commonly obscured by NGS errors.

New Developments in Systemic Management for High-Risk Early-Stage Hormone-Receptor-Positive, HER2-Negative Breast Cancer

OPINION STATEMENT

For high-risk early-stage hormone-receptor-positive, HER2-negative breast cancer (HR + /HER2 - EBC), short- and long-term recurrence risks remain substantial despite local control with surgery and radiation and systemic treatment with chemotherapy and endocrine therapy (ET). Recent trials have provided new strategies for reducing recurrence. The monarchE trial demonstrated that adding 2 years of adjuvant abemaciclib to ET improves invasive disease-free survival (iDFS) and distant recurrence-free survival (DRFS). In the OlympiA trial for high-risk disease in patients with germline BRCA1/BRCA2 mutations, adding 1 year of olaparib to ET improved iDFS, DRFS, and overall survival (OS). In addition, for premenopausal women with high-risk tumors, long-term follow-up of the SOFT, ASTRRA, TEXT, ABCSG-12, and HOBOE trials supports the role of ovarian function suppression (OFS), in combination with adjuvant tamoxifen or aromatase inhibition (AI). For postmenopausal women with high-risk tumors, extended-duration AI for at least 7 years should be used with zoledronic acid. Given the remaining recurrence risk even with these interventions and with the ongoing development of new strategies for HR + disease, patients with high-risk EBC should be encouraged to participate in clinical trials, such as trials of immunotherapy, novel oral estrogen receptor alpha (ERα)-targeting agents, antibody-drug conjugates (ADCs), and trials guided by measurements of minimal residual disease (MRD).

Circulating tumor DNA association with residual cancer burden after neoadjuvant chemotherapy in triple-negative breast cancer in TBCRC 030

Purpose

To examine circulating tumor DNA (ctDNA) and its association with residual cancer burden (RCB) using an ultrasensitive assay in patients with triple-negative breast cancer (TNBC) receiving neoadjuvant chemotherapy (NAT).

Patients and Methods

We identified responders (RCB-0/1) and matched non-responders (RCB-2/3) from the phase II TBCRC 030 prospective study of neoadjuvant paclitaxel vs. cisplatin in TNBC. We collected plasma samples at baseline, three weeks, and twelve weeks (end of therapy). We created personalized ctDNA assays utilizing MAESTRO mutation enrichment sequencing. We explored associations between ctDNA and RCB status and disease recurrence.

Results

Of 139 patients, 68 had complete samples and no additional NAT. Twenty-two were responders and 19 of those had sufficient tissue for whole-genome sequencing. We identified an additional 19 non-responders for a matched case-control analysis of 38 patients using a MAESTRO ctDNA assay tracking 319-1000 variants (median 1000) to 114 plasma samples from 3 timepoints. Overall, ctDNA positivity was 100% at baseline, 79% at week 3, and 55% at week 12. Median tumor fraction (TFx) was 3.7 × 10 -4 (range: 7.9 × 10 -7 to 4.9 × 10 -1 ). TFx decreased 285-fold from baseline to week 3 in responders and 24-fold in non-responders. Week 12 ctDNA clearance correlated with RCB: clearance was observed in 10/11 patients with RCB-0, 3/8 with RCB-1, 4/15 with RCB-2, and 0/4 with RCB-3. Among 6 patients with known recurrence five had persistent ctDNA at week 12.

Conclusion

NAT for TNBC reduced ctDNA TFx by 285-fold in responders and 24-fold in non-responders. In 58% (22/38) of patients, ctDNA TFx dropped below the detection level of a commercially available test, emphasizing the need for sensitive tests. Additional studies will determine if ctDNA-guided approaches can improve outcomes.

Abstract PD17-05: Development and Validation of a Composite Biomarker Predictive of Palbociclib + Endocrine Treatment Benefit in Early Breast Cancer: PENELOPE-B and PALLAS Trials

Background: The PENELOPE-B (NCT01864746) and PALLAS (NCT02513394) trials are large prospective, randomized, phase III trials that evaluated adjuvant palbociclib (PAL) + endocrine treatment (ET) vs ET in patients with hormone receptor–positive/human epidermal growth factor receptor 2–negative (HER2–) early breast cancer (EBC). Both studies did not meet the primary endpoint of improving invasive disease-free survival (iDFS). We conducted biomarker analyses to identify patients who might benefit from PAL + ET in EBC. Methods: Resected tumor tissue was collected from consenting patients. Gene expression analyses were conducted using the HTG EdgeSeq Oncology Biomarker Panel including 2549 genes. Based on 91 genes from the HTG panel, the intrinsic molecular subtypes were calculated using Absolute Intrinsic Molecular Subtyping (AIMS). Potential predictive treatment biomarkers were established in PENELOPE-B (n=906 with resected tissue) as the development set using an outcome-oriented approach based on iDFS with a selection procedure that maximized the log-rank statistic to estimate a standard Z score–based optimal cutoff. Independent validation was conducted on PALLAS (n=2085; PENELOPE-B-like with resected tissue and HTG data). Hazard ratios and corresponding 95% CIs were calculated using the Cox proportional hazards model, and iDFS distributions between treatment arms were compared using the log-rank test. Interaction between treatment and biomarker status was assessed. Results: Patient baseline characteristics were well balanced, with no differences in iDFS between the intent-to-treat set and the biomarker set for both trials. Approximately 73% of patients (PENELOPE-B [n=663] and PALLAS [n=1516]) had luminal A subtypes whereas only 7.1 % (PENELOPE-B [n=64]) and 8.3 % (PALLAS [n=172]) had a luminal B subtype. AIMS subtypes showed overall similar prognostic patterns for iDFS between PENELOPE-B and PALLAS. The biomarker-defined subgroup found in PENELOPE-B with optimal cutoff demonstrated a preferential benefit from PAL + ET (n=364 [96 events]; hazard ratio [95% CI], 0.63 [0.42, 0.95]; P=0.025). Independent validation of the PALLAS subgroup using the pre-defined optimal cutoff confirmed a significant benefit from PAL + ET (n=916 [70 events]; 0.55 [0.34–0.90]; P=0.015) while not in the rest of the patients (interaction p=0.0025). Significant treatment effects remained (0.55 [0.34–0.89]; P=0.015) after adjusting for the randomization stratification factors of PALLAS. Conclusions: The composite predictive biomarker defined from PENELOPE-B was independently validated in a prospectively defined retrospective analysis of a subset of patients selected from PALLAS. The composite biomarker identified a subset of EBC patients deriving benefit from the addition of PAL to ET. This patient stratification approach can potentially be applied to future adjuvant clinical trials for treatment of hormone receptor–positive/HER2– EBC.

Citation Format: Sibylle Loibl, Carsten Denkert, Yuan Liu, Erik S. Knudsen, Angela DeMichele, Zhe Zhang, Julia Teply-Szymanski, Martin Filipits, Peter A. Fasching, Michael Gnant, Shibing Deng, Marija Balic, Federico Rojo, Mark Watson, Chetan Deshpande, Nicholas Turner, Otto Metzger, Kathy Puyana Theall, Agnieszka Witkiewicz, Olga Valota, W. Fraser Symmans, Erica L. Mayer. Development and Validation of a Composite Biomarker Predictive of Palbociclib + Endocrine Treatment Benefit in Early Breast Cancer: PENELOPE-B and PALLAS Trials [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 PD17-05.

Design of SERENA-6, a phase III switching trial of camizestrant in ESR1-mutant breast cancer during first-line treatment

ESR1 mutation (ESR1m) is a frequent cause of acquired resistance to aromatase inhibitor (AI) plus cyclin-dependent kinase 4 and 6 inhibitors (CDK4/6i), which is a first-line therapy for hormone-receptor-positive (HR+)/human epidermal growth factor receptor 2-negative (HER2-) advanced breast cancer (ABC). Camizestrant is a next-generation oral selective estrogen receptor degrader (SERD) that in a phase II study significantly improved progression-free survival (PFS) over fulvestrant (also a SERD) in ER+/HER2- ABC. SERENA-6 (NCT04964934) is a randomized, double-blind, phase III study evaluating the efficacy and safety of switching from an AI to camizestrant, while maintaining the same CDK4/6i, upon detection of ESR1m in circulating tumor DNA before clinical disease progression on first-line therapy for HR+/HER2- ABC. The aim is to treat ESR1m clones and extend the duration of control of ER-driven tumor growth, delaying the need for chemotherapy. The primary end point is PFS; secondary end points include chemotherapy-free survival, time to second progression event (PFS2), overall survival, patient-reported outcomes and safety.

Abstract GS3-06: GS3-06 Palbociclib After CDK4/6i and Endocrine Therapy (PACE): A Randomized Phase II Study of Fulvestrant, Palbociclib, and Avelumab for Endocrine Pre-treated ER+/HER2- Metastatic Breast Cancer

Background CDK4/6 inhibitors (CDK4/6i) in combination with endocrine therapy (ET) have a well-established role in the management of hormone receptor-positive (HR+)/HER2- metastatic breast cancer (MBC). The benefit of continuing CDK4/6i beyond progression in combination with a different ET has not been confirmed. Preclinical data suggest synergy between CDK4/6i and PD-L1 inhibition. The PACE trial prospectively evaluates whether continuation of the CKD4/6i palbociclib beyond progression on prior CDK4/6i and aromatase inhibitor (AI), with a change in ET to fulvestrant, improves outcomes beyond change to fulvestrant alone, as well as explores the activity of the palbociclib, fulvestrant, and avelumab triplet. Methods PACE is a multicenter randomized open-label investigator-initiated phase II trial, open at 11 U.S. sites. Eligible patients (pts) had HR+/HER2- evaluable MBC with prior progression on AI and any CDK4/6i after &gt; 6 months (mo) of therapy in the MBC setting, or during/within 12 mo in the adjuvant setting, with no more than 1 prior line of chemotherapy for MBC. Pts were randomized 1:2:1 to fulvestrant alone (F); fulvestrant and palbociclib (F+P); or fulvestrant, palbociclib, avelumab (F+P+A), with tumor assessments every 8 weeks. Blood for circulating tumor DNA (ctDNA) analysis was collected at baseline, at times of tumor assessments, and at progression. The primary objective was to evaluate progression-free survival (PFS) with F+P vs F; secondary objectives included PFS with F+P+A vs F, objective response rate (ORR) in all arms, and safety. A sample size of 220 patients was planned to provide 80% power to detect an improvement in PFS with HR 0.6154 with F+P vs F (6.5 vs 4 mo; α(1)=0.05). Results A total of 220 pts were randomized from 9/2017-2/2022 (F: n=55, F+P: n=111, F+P+A: n=54); median age 57 years (range 25-83), 85% non-Hispanic (7.7% non-Hispanic black), 8.6% Hispanic, 6.4% unknown. 40% had de novo MBC, 60% had visceral disease, and 14% bone-only disease. 16% had 1 prior line of chemotherapy for MBC, 90% had received prior palbociclib, 4.5% ribociclib, 4.1% abemaciclib, 1.4% palbociclib and ribociclib. Pts entered the trial after a median 19 mo of prior CDK4/6i plus AI (interquartile range 12-31 mo). A total of 10 (5%) pts received protocol therapy as first line ET for MBC, 169 (77%) as second line, and 41 (17%) as beyond second line. 88% entered the trial directly after progression on CDK4/6i. After a median follow-up of 24 mo, 18 pts remained on protocol treatment. PFS was not improved with F+P vs F (median 4.6 vs 4.8 mo; HR=1.11, 90% CI 0.79-1.55; 2-sided p=0.62). Median PFS was 8.1 mo with F+P+A (HR=0.75 vs F, 90% CI 0.50-1.12; 2-sided p=0.23). ORR was 7.3% (90%CI 1.5-13.0) with F, 9.0% F+P (4.5-13.5%) and 13.0% F+P+A (5.4-20.5%). No new safety signals have been observed. Analysis of ctDNA panel sequencing encompassing 70 genes from 184 baseline samples, including correlation with known and hypothesized resistance genes, will be presented. Conclusions For ER+/HER2- breast cancer, combining palbociclib with fulvestrant beyond progression on prior CDK4/6i and AI did not significantly improve PFS compared with using fulvestrant alone. The observed longer PFS when a PD-L1 inhibitor was added to fulvestrant plus palbociclib is an intriguing signal in this ER+ population. Translational studies of blood and tumor tissue are ongoing and will be presented.

Citation Format: Erica L. Mayer, Yue Ren, Nikhil Wagle, Reshma Mahtani, Cynthia Ma, Angela DeMichele, Massimo Cristofanilli, Jane Meisel, Kathy D. Miller, Trevor Jolly, Elizabeth Riley, Rubina Qamar, Priyanka Sharma, Sonya Reid, Natalie Sinclair, Meredith Faggen, Caroline Block, Naomi Ko, Ann Partridge, Wendy Y. Chen, Michelle K. DeMeo, Victoria Attaya, Amanda Okpoebo, Yuan Liu, Eric Gauthier, Harold Burstein, Meredith Regan, Sara Tolaney. GS3-06 Palbociclib After CDK4/6i and Endocrine Therapy (PACE): A Randomized Phase II Study of Fulvestrant, Palbociclib, and Avelumab for Endocrine Pre-treated ER+/HER2- Metastatic 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 GS3-06.

Abstract PD11-06: PD11-06 Circulating tumor DNA association with residual cancer burden after neoadjuvant therapy in triple negative breast cancer in TBCRC 030

Background. Patients (pts) with early triple negative breast cancer (eTNBC) are at increased risk of breast cancer recurrence and death. Recent studies have focused on escalation of therapy, with current treatment standard of at least five drugs – and associated toxicities - for eTNBC. Though presence of residual disease after neoadjuvant therapy (NAT) as measured by residual cancer burden (RCB) helps guide addition of adjuvant treatment, more effective tools to tailor therapy are limited. Persistence of circulating tumor DNA (ctDNA) in the setting of residual disease is associated with high risk of distant recurrence. However, more sensitive minimal residual disease (MRD) assays are needed to potentially guide optimization of systemic therapy.

Methods. TBCRC 030 is a phase II randomized study of 12 weeks of NAT single agent cisplatin or paclitaxel for stage II-III TNBC, followed by surgery. The primary objective of the parent study was to correlate baseline biomarker for homologous recombination deficiency and RCB by study arm. From this group, responders (RCB 0/1) and non-responders (RCB 2/3) from both study arms who did not receive additional NAT prior to surgery were selected for analysis from the study cohort, matched on baseline nodal status and tumor size. As a post hoc study amendment, available pts were followed for event free survival (EFS). Plasma samples were collected prior to treatment initiation (W0), at three weeks (W3), and at twelve weeks, prior to surgery (W12). Whole genome sequencing (WGS) was performed on primary tumor tissue to identify somatic mutations and design for each pt a tumor-informed, ctDNA assay tracking up to 1000 mutations to detect MRD. Detection limit was computed for each tested sample as previously described. For each sample assayed, we report tumor fraction (TFx) when MRD was detected and the detection limit at 90% power when MRD was not detected.

Results. Of 139 study pts, 68 had complete tissue and plasma samples and no receipt of additional NAT. Of these, 22 were responders. These responders, and 22 matched non-responders were identified for analysis. Data from 22 pts – 11 responders, 11 non-responders - are described here; full analysis on all 44 pts will be presented at the meeting. Personalized ctDNA assays were designed targeting 434 to 1000 variants (median 1000) and applied to 66 plasma samples. At W0, 100% (22/22) were positive for ctDNA; 73% (16/22) and 55% (12/22) were positive at W3, and W12, respectively. In pts with T1-T2 tumors median TFx was 4.1e-3(7.8e-6, 3.4e-2) and 4.7e-1(4.3e-2, 9.0e-1) in pts with T3-T4 tumors. TFx decreased from W0 to W3 and from W0 to W12 in responders (Table 1). By W12, ctDNA had cleared in 7/8 pts with RCB 0, 1/3 with RCB 1, 2/8 with RCB 2, and 0/3 with RCB 3. Overall, ctDNA levels were broad with median TFx of 1.5e-3 (range 2.9e-6 to 0.90). Detection limit at 90% power for all tested samples was a median of 8.8e-6 (range 9.9e-7 to 6.8e-3).

To investigate whether ctDNA persistence after NAT was associated with BC recurrence, we analyzed a separate group of all 8 pts with known recurrence and with complete data and samples. All pts had persistent ctDNA at W12 (median TFx 6.8e-3, [2.9e-6 to 6.6e-2]).

Conclusions. After 3 weeks of NAT for eTNBC, ctDNA TFx decreased, with a 3900-fold change in responders and 18-fold change in non-responders. By W3, TFx for most pts with RCB 0/1 were below the 1 in 10,000 limit of detection for many currently available assays, emphasizing the need for sensitive tests to potentially guide therapy. Additional studies will determine if ctDNA-guided approaches in eTNBC can improve pt outcomes.

Table 1: Tumer Fraction and Tumer Fraction Fold Change by Response to Neoadjuvant Therapy

Citation Format: Heather A. Parsons, Timothy Blewett, Xiangying Chu, Sainetra Sridhar, Katheryn Santos, Kan Xiong, Vandana Abramson, Ashka Patel, Ju Cheng, Adam M. Brufsky, Justin Rhoades, Jeremy Force, Ruolin Liu, Tiffany A. Traina, Lisa Carey, Mothaffar Rimawi, Ahmed Elkhanany, Vered Stearns, Jennifer M. Specht, Harold Burstein, Antonio C. Wolff, Eric Winer, Nabihah Tayob, Ian Krop, Todd Golub, Erica L. Mayer, Viktor Adalsteinsson. PD11-06 Circulating tumor DNA association with residual cancer burden after neoadjuvant therapy in triple negative breast cancer in TBCRC 030 [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 PD11-06.

Abstract OT2-01-07: evERA Breast Cancer: A phase III study of giredestrant (GDC-9545) + everolimus vs exemestane + everolimus in patients with estrogen receptor+, HER2– locally advanced or metastatic breast cancer

BACKGROUND Endocrine therapy (ET) modulates estrogen synthesis and/or estrogen receptor (ER) activity and is the mainstay of ER+ breast cancer (BC) treatment. ET + a cyclin-dependent kinase 4/6 inhibitor (CDK4/6i) is the standard of care in patients (pts) with ER+, HER2– metastatic BC (mBC) in the first-line setting. Fulvestrant ± a CDK4/6i, and everolimus + exemestane, are the current regimens approved for use in the second-line setting. However, therapeutic resistance to some ETs, such as aromatase inhibitors, can arise from ESR1 mutations driving estrogen-independent transcription and proliferation. Current post-CDK4/6i treatment options are suboptimal. New therapy options are therefore needed to reduce this risk and to improve outcomes, tolerability, quality of life, and adherence to treatment. Giredestrant is a highly potent, nonsteroidal oral selective ER antagonist and degrader (SERD) that achieves robust ER occupancy and is active regardless of ESR1 mutation status. While phase I SERD combination data in the post CDK4/6 setting is encouraging, there is no randomized combination data. Combining giredestrant and everolimus may potentially improve outcomes after CDK4/6is and in pts with ESR1-mutated tumors; evERA BC is investigating this combination to address the unmet need in the post-CDK4/6i setting. TRIAL DESIGN This phase III, global, randomized, open-label, multicenter study will evaluate the efficacy and safety of giredestrant + everolimus vs exemestane + everolimus in pts with ER+/HER2– locally advanced (LA)/mBC who had previous treatment with a CDK4/6i and ET in the LABC/mBC or adjuvant setting. Pts will be randomized to either giredestrant (30 mg) + everolimus (10 mg) by mouth (PO) every day (QD) on Days 1–28 of each 28-day cycle, or exemestane (25 mg) + everolimus (10 mg) PO QD on Days 1–28 of each 28-day cycle. Pts will receive treatment until disease progression or unacceptable toxicity. Pts will use a dexamethasone mouth rinse four times QD for 8 weeks, started concurrently with study treatment. ELIGIBILITY Female/male pts ≥18 years with ER+/HER2– LA/mBC, an Eastern Cooperative Oncology Group Performance Status of 0–1, measurable disease defined per RECIST v.1.1 (or evaluable bone metastases with at least one predominantly lytic bone lesion confirmed by computed tomography or magnetic resonance imaging), disease progression ≥6 months after initiating ET + CDK4/6i in the LABC/mBC setting (and ≥4 months on most recent ET, if ET + a CDK4/6i was not the most recent therapy received), or relapsed either while taking or within 12 months of exposure to combination adjuvant ET (≥12 months) and a CDK4/6i (≥6 months). Availability of a baseline blood sample to determine ESR1 mutation status by circulating tumor DNA assay for testing at a central laboratory. Men and pre-/perimenopausal women will receive a luteinizing hormone-releasing hormone agonist on Day 1 of each 28-day cycle. AIMS Primary endpoint: investigator-assessed progression-free survival (PFS; per RECIST v1.1). Secondary endpoints: investigator-assessed PFS in pts with detectable ESR1-mutated tumors in circulating tumor DNA at baseline; overall survival; objective response rate; duration of response; clinical benefit rate; patient-reported outcomes; safety; pharmacokinetics. STATISTICAL METHODS The primary endpoint analysis will use a stratified log-rank test at an overall 0.05 significance level (two-sided). An independent data monitoring committee will be in place for safety. ACCRUAL Target enrollment is 224 pts globally, and this study is currently recruiting. CONTACT INFORMATION For more information or to refer a patient, email global.rochegenentechtrials@roche.com or call 1-888-662-6728 (USA only). Clinicaltrials.gov number NCT05306340.

Citation Format: Erica L. Mayer, Sara Tolaney, Adam M. Brufsky, William Gradishar, Komal Jhaveri, Miguel Martín, Luca Moscetti, Gregory Vidal, Patricia Cortazar, Merilin Feldman, Bann-mo Day, Hope Rugo. evERA Breast Cancer: A phase III study of giredestrant (GDC-9545) + everolimus vs exemestane + everolimus in patients with estrogen receptor+, HER2– locally advanced or metastatic 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 OT2-01-07.

'ADVANCE' (a pilot trial) ADjuVANt chemotherapy in the elderly: Developing and evaluating lower-toxicity chemotherapy options for older patients with breast cancer

INTRODUCTION

Older adults with breast cancer receiving neo/adjuvant chemotherapy are at high risk for poor outcomes and are underrepresented in clinical trials. The ADVANCE (ADjuVANt Chemotherapy in the Elderly) trial evaluated the feasibility of two neo/adjuvant chemotherapy regimens in parallel-enrolling cohorts of older patients with human epidermal growth factor receptor 2-negative breast cancer: cohort 1-triple-negative; cohort 2-hormone receptor-positive.

MATERIALS AND METHODS

Adults age ≥ 70 years with stage I-III breast cancer warranting neo/adjuvant chemotherapy were enrolled. Cohort 1 received weekly carboplatin (area under the curve 2) and weekly paclitaxel 80 mg/m2 for twelve weeks; cohort 2 received weekly paclitaxel 80 mg/m2 plus every-three-weekly cyclophosphamide 600 mg/m2 over twelve weeks. The primary study endpoint was feasibility, defined as ≥80% of patients receiving ≥80% of intended weeks/doses of therapy. All dose modifications were applied per clinician discretion.

RESULTS

Forty women (n = 20 per cohort) were enrolled from March 25, 2019 through August 3, 2020 from three centers; 45% and 35% of patients in cohorts 1 and 2 were age > 75, respectively. Neither cohort achieved targeted thresholds for feasibility. In cohort 1, eight (40.0%) met feasibility (95% confidence interval [CI] = 19.1-63.9%), while ten (50.0%) met feasibility in cohort 2 (95% CI = 27.2-72.8). Neutropenia was the most common grade 3-4 toxicity (cohort 1-65%, cohort 2-55%). In cohort 1, 80% and 85% required ≥1 dose holds of carboplatin and/or paclitaxel, respectively. In cohort 2, 10% required dose hold(s) for cyclophosphamide and/or 65% for paclitaxel.

DISCUSSION

In this pragmatic pilot examining chemotherapy regimens in older adults with breast cancer, neither regimen met target goals for feasibility. Developing efficacious and tolerable regimens for older patients with breast cancer who need chemotherapy remains an important goal.

CLINICALTRIALS

gov Identifier: NCT03858322.

Mutational Signature 3 Detected from Clinical Panel Sequencing is Associated with Responses to Olaparib in Breast and Ovarian Cancers

PURPOSE

The identification of patients with homologous recombination deficiency (HRD) beyond BRCA1/2 mutations is an urgent task, as they may benefit from PARP inhibitors. We have previously developed a method to detect mutational signature 3 (Sig3), termed SigMA, associated with HRD from clinical panel sequencing data, that is able to reliably detect HRD from the limited sequencing data derived from gene-focused panel sequencing.

EXPERIMENTAL DESIGN

We apply this method to patients from two independent datasets: (i) high-grade serous ovarian cancer and triple-negative breast cancer (TNBC) from a phase Ib trial of the PARP inhibitor olaparib in combination with the PI3K inhibitor buparlisib (BKM120; NCT01623349), and (ii) TNBC patients who received neoadjuvant olaparib in the phase II PETREMAC trial (NCT02624973).

RESULTS

We find that Sig3 as detected by SigMA is positively associated with improved progression-free survival and objective responses. In addition, comparison of Sig3 detection in panel and exome-sequencing data from the same patient samples demonstrated highly concordant results and superior performance in comparison with the genomic instability score.

CONCLUSIONS

Our analyses demonstrate that HRD can be detected reliably from panel-sequencing data that are obtained as part of routine clinical care, and that this approach can identify patients beyond those with germline BRCA1/2mut who might benefit from PARP inhibitors. Prospective clinical utility testing is warranted.

Adjuvant palbociclib for ER+ breast cancer (PALLAS Trial (ABCSG-42/AFT-05/PrE0109/BIG-14-13): A preplanned analysis of the stage IIA cohort

390216

Background: CDK4/6 inhibitors have become standard of care for advanced hormone receptor positive, HER2-negative (HR+/HER2-) breast cancer in combination with endocrine therapy (ET), with one approved for high-risk patients (pts) in the adjuvant setting. The PALLAS Trial investigated the addition of palbociclib to adjuvant ET in pts with stage II-III breast cancer. Stage IIA patients were specifically enrolled to evaluate the potential benefit of using palbociclib with adjuvant ET pts diagnosed at lower risk who may have more indolent disease. Methods: In the prospective, randomized, phase III PALLAS trial, pts with HR+/HER2- early breast cancer were randomly assigned to receive adjuvant ET for at least 5 years with or without 2 years of palbociclib (125 mg orally once daily, days 1-21 of a 28-day cycle). ET was of provider’s choice. Stage IIA enrollment was capped at 1,000 patients. While the primary end point of the overall study was invasive disease-free survival (iDFS) for the entire cohort, there was a preplanned analysis of recurrence and survival endpoints in the stage IIA cohort. Outcomes were compared between arms using stratified log-rank tests and Cox models (stratification factors: chemotherapy and age ≤ 50). Results: Among 5,796 pts enrolled at 406 centers in 21 countries worldwide between 9/1/2015 and 11/30/2018, a total of 1,010 stage IIA pts were enrolled. The protocol-defined number of events occurred at a median follow-up of 50 months for this subgroup (43.1 months for the overall study). Median age within this subgroup was 54 (range 29-85 yrs), and 410 (40.6%) were pre/perimenopausal, 506 (50.1%) T2/N0 (vs T0-1/N1), 272 (26.9%) grade 3 (vs. grade1/2), and 561 (55.5%) received chemotherapy. iDFS events occurred in 31 of 503 (6.2%) pts who received palbociclib plus ET and in 45 of 507 (8.9%) pts who received ET alone, resulting in a statistically nonsignificant difference in iDFS at 4 years (92.9% vs. 92.1%; hazard ratio, 0.75; CI, 0.48 to 1.19; P = .23). Nonsignificant differences were also observed for invasive breast cancer-free, distant recurrence-free, and locoregional cancer-free survival. No significant differences in iDFS were observed in subgroups including age group, receipt of chemotherapy, tumor grade, and clinical risk (T1/N1 vs. T2/N0).Conclusions: In this preplanned analysis of the stage IIA cohort of the PALLAS trial, the addition of adjuvant palbociclib to standard ET did not improve outcomes over ET alone, suggesting no benefit from the agent in reducing the incidence of early relapse in pts with lower-stage HR+/HER2- breast cancer. Future analyses will incorporate genomic risk and other molecular patterns from the extensive transPALLAS correlative program. Additional follow-up (10-year minimum) is also underway to assess the impact of palbociclib exposure on late recurrence in HR+ disease. Clinical trial information: NCT02513394.

Outcomes after treatment of breast cancer during pregnancy including taxanes and/or granulocyte colony-stimulating factor use: findings from a multi-institutional retrospective analysis

BACKGROUND

Guidelines support comparable treatment for women diagnosed with breast cancer during pregnancy (PrBC) and nonpregnant women with limited case-specific modifications to ensure maternal-fetal safety. Experience during pregnancy with modern agents, such as taxanes or granulocyte colony-stimulating factors (GCSF), is limited.

PATIENTS AND METHODS

We retrospectively identified a multi-institutional cohort of PrBC between 1996 and 2020. Propensity score analyses with multiple imputation for missing variables were applied to determine the associations between chemotherapy exposures during pregnancy, with or without taxanes or GCSF, and a compound maternal-fetal outcome including spontaneous preterm birth, preterm premature rupture of membranes, chorioamnionitis, small for gestational age newborns, congenital malformation, or 5-min Apgar score < 7.

RESULTS

Among 139 PrBC pregnancies, 82 (59.0%) were exposed to chemotherapy, including 26 (31.7%) to taxane and 18 (22.0%) to GCSF. Chemotherapy use, in general, and inclusion of taxane and/or GCSF, specifically, increased over time. Pregnancies resulting in live singleton births (n = 123) and exposed to chemotherapy were as likely to reach term as those that were not (59.5% vs. 63.6%, respectively, p_unadjusted = 0.85). Among women treated with chemotherapy, propensity score-matched odds ratios (OR) for the composite maternal-fetal outcome were not significantly increased with taxane (OR 1.24, 95% CI 0.27-5.72) or GCSF (OR 2.11, 95% confidence interval (CI) 0.48-9.22) with similar effects in multiple imputation and sensitivity models.

CONCLUSION

The judicious increased use of taxane chemotherapy and/or growth factor support during pregnancy was not associated with unfavorable short-term maternal-fetal outcomes. While these findings are reassuring, case numbers remain limited and continued surveillance of these patients and progeny is warranted.

Exploring homologous recombination deficiency thresholds for predicting response to platinum-based treatment in triple negative breast cancer

525

Background: Homologous recombination deficiency (HRD) status can be used to identify patients who are eligible for treatment with DNA damaging agents. Using a 3-biomarker Genomic Instability Score (GIS) threshold of ≥42, studies have previously examined the association between HRD status and outcomes in patients with triple negative breast cancer (TNBC). However, evidence suggests that a GIS threshold of ≥33 may be more appropriate. Here, we conducted an exploratory analysis evaluating the ability of ≥33 and ≥42 GIS thresholds to predict response to platinum-based treatment in patients with TNBC. Methods: Patients across 5 cohorts (TBCRC0301, TBCRC0082, NCT013725793, PrECOG 01054, combined cisplatin cohort4) were included in this analysis if they had a primary TNBC diagnosis, received neoadjuvant platinum-based treatment, had a valid GIS, and had known pathologic complete response (pCR) status. GIS was determined by a combination of loss of heterozygosity, telomeric-allelic imbalance, and large-scale state transitions.4,5 BRCA mutation status was defined by loss of function resulting from a pathogenic variant in BRCA1 or BRCA2. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV), were calculated by comparing binary threshold status and binary pCR status. Results: A total of 204 tumors (158 BRCAwt; 33 BRCAm; 13 unknown) were included; pCR to platinum-based treatment occurred in 55 cases (39 BRCAwt; 14 BRCAm; 2 unknown). Sensitivity, specificity, PPV, and NPV were comparable between the ≥33 and ≥42 GIS thresholds, with the ≥33 threshold producing higher sensitivity values. This was true when thresholds were applied to all samples and to BRCAwt samples only (Table). Among patients who achieved pCR in response to platinum-based treatment, 5.5% of patients in the full cohort and 7.7% of those in the BRCAwt cohort had a GIS between 33-41. Conclusions: To ensure that the majority of patients likely to benefit from treatment are identified, a GIS of ≥33 may be the most appropriate threshold to predict response to platinum-based treatment in patients with TNBC; however, a prospective trial will be needed to confirm these findings. Additional studies will be important to determine whether this threshold may be appropriate to determine eligibility for other DNA-damaging agents such as PARP inhibitors. 1. Ann Oncol. 2020;31(11):1518-25 2. J Nucl Med. 2015;56(1):31-7. 3. Breast Cancer Res Treat. 2015;151(3):629-38. 4. Clin Cancer Res. 2016;22(15):3764-73. 5. Breast Cancer Res Treat. 2014;16(6):1-9. [Table: see text]

Impact of body mass index on treatment and outcomes in patients with early hormone receptor-positive breast cancer receiving endocrine therapy with or without palbociclib in the PALLAS trial

518

Background: Body Mass Index (BMI) impacts breast cancer risk and prognosis. Conflicting results have been published regarding BMI as a predictive factor for endocrine therapy benefit. CDK4/6 inhibitors (CDK4/6i) in combination with endocrine treatment (ET) are standard-of-care treatments for metastatic hormone receptor-positive breast cancer. In contrast to cytotoxic chemotherapy, CDK4/6i are given at a fixed dose irrespective of BMI or weight. The PALLAS trial compared the combination of the CDK4/6i palbociclib and adjuvant ET to ET alone in the early breast cancer setting. This analysis investigates the impact of BMI on the efficacy and the side effect profile of palbociclib (P) in the PALLAS trial. Methods: In this pre-planned analysis, patients (pts) enrolled in PALLAS were categorized according to BMI as underweight (BMI <18.5 kg/m2), normal weight (BMI 18.5-24.9 kg/m2), overweight (BMI 25-29.9 kg/m2) and obese (³30 kg/m2), respectively. Adverse event differences were assessed with Chi-squared tests. Time to early discontinuation of P was analyzed with Fine and Gray competing risk models. Cox models were used to investigate the association between BMI category and time to invasive disease-free survival (iDFS). Results: Of a total of 5698 pts included in this analysis, 68 (1.2%) were underweight, 2082 (36.5%) normal weight, 1818 (31.9%) overweight and 1730 (30.4%) obese at baseline. Significantly different rates of all grade neutropenia were observed in normal weight, overweight and obese pts with regard to total (88.5%, 85.7% and 74.7%), as well as grade 3 (64.1%, 62.0% and 43.9%) and grade 4 neutropenia (7.0%, 3.6% and 2.0%), respectively. The lower frequency and severity of neutropenia observed in overweight and obese pts was associated with a significant lower treatment discontinuation rate over time when compared to normal weight patients (overweight vs normal weight: HR 0.73 CI 0.63-0.84, p<0.0001, and obese vs normal weight: HR 0.65 CI 0.56-0.75, p<0.0001). In pts treated with P, neutropenia was the primary toxicity leading to treatment discontinuation in 21.1% of normal weight pts, 14.0% of overweight pts and 5.9% obese pts, respectively. Despite these observations, there was no statistically significant improvement in iDFS with the addition of P to ET in any weight category (normal weight HR 0.84 CI 0.63-1.12, overweight HR 1.10 CI 0.82-1.49 and obese HR 0.95 CI 0.69-1.30). Conclusions: This pre-planned analysis of outcomes by BMI in the PALLAS trial demonstrates significantly less frequent and less severe neutropenia in overweight and obese pts compared to those with normal weight, leading to significant lower treatment discontinuation rates. However, no difference in iDFS outcomes by BMI was observed. Additional long-term follow-up will further evaluate whether BMI ultimately impacts outcome. Clinical trial information: NCT02513394.

Racial/ethnic disparities in locoregional recurrence in hormone-receptor positive node-negative breast cancer patients enrolled in the TAILORx trial

515

Background: Whether racial/ethnic disparities in locoregional recurrence (LRR) exist in patients (pts) with similar access to care treated on clinical trials is uncertain. We examined racial/ethnic differences in LRR in hormone-receptor positive HER2-negative (HR+HER2-) node-negative pts enrolled in the TAILORx trial. Methods: 10,273 pts age 18-75 were enrolled in TAILORx, which assigned pts with an OncotypeDx Recurrence Score (RS) <11 to endocrine therapy (ET) alone, those with RS >25 to chemotherapy + ET (CET), and randomized pts with RS 11-25 to ET or CET. Pts with unknown race/ethnicity (n=323) or incomplete treatment adherence information (n=1,168) were excluded from this analysis. Race/ethnicity was self-reported. LRR was defined as ipsilateral invasive in-breast, chest wall, or regional nodal recurrence without distant recurrence. Kaplan-Meier curves were used to estimate 8-year LRR. Cox proportional hazards analysis adjusted for clinical and treatment factors was used to determine factors associated with LRR. Results: 8,782 pts with T1-2N0 HR+HER2- breast cancer were included. Race/ethnicity was non-Hispanic White (NHW) in 6,932 (78.9%), non-Hispanic Black (NHB) in 629 (7.2%), Hispanic in 818 (9.3%), and Asian in 403 (4.6%). Treatment adherence was high across groups over time, with a 9.1% crossover in treatment arms. Average duration of ET was 63.8 +/- 0.3 months. Radiation therapy was planned in 96.0% of pts after breast conservation and 12.7% after mastectomy. At a median follow-up of 8 years, LRR rates were 1.9% in NHW, 4.2% in in NHB, 3.2% in Hispanic, and 3.9% in Asian pts (p<0.01). LRR rates broken down by RS are shown in the Table. On adjusted analyses, NHB and Asian (vs. NHW) pts were more likely to have LRR (HR 1.94 for NHB, HR 2.04 for Asian, p<0.05 for both). Additional statistically significant factors associated with LRR included age <50 (HR 1.85), T2 tumors (HR 1.43), higher grade (HR 2.30 for grade 3), and high RS (HR 3.13 for RS>25). Treatment receipt (chemotherapy, ET duration, and radiation) was not associated with LRR in this population. Conclusions: Racial/ethnic differences in LRR were seen in T1-2N0 HR+HER2- breast cancer pts enrolled in the TAILORx trial despite high rates of treatment adherence in this clinical trial population, with highest LRR rates in NHB and Asian pts. Further study in needed to understand racial/ethnic patterns in LRR by breast cancer subtype and if failure to rescue after LRR may contribute to differences in breast cancer mortality.[Table: see text]

Biomarkers for Adjuvant Endocrine and Chemotherapy in Early-Stage Breast Cancer: ASCO Guideline Update

PURPOSE

To update recommendations on appropriate use of breast cancer biomarker assay results to guide adjuvant endocrine and chemotherapy decisions in early-stage breast cancer.

METHODS

An updated literature search identified randomized clinical trials and prospective-retrospective studies published from January 2016 to October 2021. Outcomes of interest included overall survival and disease-free or recurrence-free survival. Expert Panel members used informal consensus to develop evidence-based recommendations.

RESULTS

The search identified 24 studies informing the evidence base.

RECOMMENDATIONS

Clinicians may use Oncotype DX, MammaPrint, Breast Cancer Index (BCI), and EndoPredict to guide adjuvant endocrine and chemotherapy in patients who are postmenopausal or age > 50 years with early-stage estrogen receptor (ER)-positive, human epidermal growth factor receptor 2 (HER2)-negative (ER+ and HER2-) breast cancer that is node-negative or with 1-3 positive nodes. Prosigna and BCI may be used in postmenopausal patients with node-negative ER+ and HER2- breast cancer. In premenopausal patients, clinicians may use Oncotype in patients with node-negative ER+ and HER2- breast cancer. Current data suggest that premenopausal patients with 1-3 positive nodes benefit from chemotherapy regardless of genomic assay result. There are no data on use of genomic tests to guide adjuvant chemotherapy in patients with ≥ 4 positive nodes. Ki67 combined with other parameters or immunohistochemistry 4 score may be used in postmenopausal patients without access to genomic tests to guide adjuvant therapy decisions. BCI may be offered to patients with 0-3 positive nodes who received 5 years of endocrine therapy without evidence of recurrence to guide decisions about extended endocrine therapy. None of the assays are recommended for treatment guidance in individuals with HER2-positive or triple-negative breast cancer. Treatment decisions should also consider disease stage, comorbidities, and patient preferences.Additional information is available at www.asco.org/breast-cancer-guidelines.

Birthweight and Chemotherapy Exposure in Women Diagnosed with Breast Cancer during Pregnancy

OBJECTIVE

Breast cancer is one of the most frequently diagnosed cancers in pregnancy and is commonly treated with chemotherapy. To date, studies examining effects of chemotherapy during pregnancy on fetal growth have yielded conflicting results, and most are limited by small sample sizes or are nonspecific with respect to cytotoxic regimen or type of cancer treated. We sought to evaluate the effect of chemotherapy for breast cancer in pregnancy on birthweight and small for gestational age infants.

STUDY DESIGN

This is a retrospective cohort study of 74 women diagnosed with pathologically confirmed breast cancer during pregnancy between 1997 and 2018 at one of three academic medical centers, who had a singleton birth with known birthweight. Forty-nine received chemotherapy and 25 did not receive chemotherapy. Linear regression modeling was used to compare birthweight (by gestational age and sex-specific z-score) by chemotherapy exposure. Subanalyses of specific chemotherapy regimen and duration of chemotherapy exposure were also performed. Placental, neonatal, and maternal outcomes were also analyzed by chemotherapy exposure.

RESULTS

In the adjusted model, chemotherapy exposure was associated with lower birthweight (Δ z-score = -0.49, p = 0.03), but similar rates of small for gestational age (defined as birthweight <10th percentile for gestational age) infants (8.2 vs. 8.0%, p = 1.0; Fisher's exact test). Each additional week of chemotherapy (Δ z-score = -0.05, p = 0.03) was associated with decreased birthweight, although no association was found with specific chemotherapy regimen. Chemotherapy exposure was associated with lower median placental weight percentile by gestational age (9th vs. 75th, p < 0.05). Secondary maternal outcomes were similar between the group that did and did not receive chemotherapy.

CONCLUSION

Chemotherapy for breast cancer in pregnancy in this cohort is associated with lower birthweight but no difference in the rate of small for gestational age infants.

KEY POINTS

· Chemotherapy for breast cancer in pregnancy is associated with decreased birthweight but similar rates of small for gestational age infants.. · Birthweight did not differ according to chemotherapy regimen.. · There is no difference in the rate of small for gestational age infants..

Abstract OT2-11-05: SERENA-6: A Phase III study to assess the efficacy and safety of AZD9833 (camizestrant) compared with aromatase inhibitors when given in combination with palbociclib or abemaciclib in patients with HR+/HER2- metastatic breast cancer with detectable ESR1m who have not experienced disease progression on first-line therapy

Background: More than two thirds of patients with metastatic breast cancer (mBC) have hormone receptor-positive (HR+), human epidermal growth factor receptor 2-negative (HER2−) tumors. Current guidelines recommend combining endocrine therapy (ET), such as an aromatase inhibitor (AI), with an inhibitor of cyclin-dependent kinases 4 and 6 (CDK4/6i) as first-line (1L) treatment (Cardoso et al. Ann Oncol 2020). However, drug resistance eventually develops, leading to disease progression. Mutations in the estrogen receptor (ER) alpha gene (ESR1m) result in constitutively active, estrogen-independent ER signaling which can reduce AI efficiency (Reinert et al. Front Oncol 2017). Clinically, ESR1m are associated with acquired resistance to AI as well as more aggressive disease features, including development of visceral metastasis (Gerratana et al. Eur J Cancer 2021). At the initial diagnosis of mBC, the frequency of ESR1m is low (approximately 3%) (Bidard et al. Ann Oncol 2019); however, this increases to 17−35% of patients when disease progresses on an AI + CDK4/6i (Bidard et al. Ann Oncol 2019; Goetz et al. J Clin Oncol 2020). Patients with ESR1m tumors have poor outcomes with subsequent lines of therapy. New approaches are needed to maximize time on 1L treatment with ET + CDK4/6i and prevent further clinical and radiological disease progression. AZD9833 (camizestrant) is a highly potent, next-generation oral selective ER degrader (ngSERD) and pure ER antagonist that has demonstrated antitumor activity in a wide range of ER+ breast cancer cell lines and patient-derived xenograft models, including those with wild type ESR1 (ESR1wt) and the most prevalent ESR1m, D538G and Y537S (Scott et al. AACR 2020; Lawsone et al. AACR 2020). The Phase I SERENA-1 study demonstrated that AZD9833 shows encouraging clinical activity as monotherapy or in combination with a CDK4/6i in heavily pre-treated patients with ER+/HER2− advanced breast cancer whose tumors are ESR1wt or ESR1m (Baird et al. SABCS 2020). SERENA-6 will assess the efficacy of switching patients from AI to AZD9833, while continuing CDK4/6i treatment, once ESR1m are detected but before overt disease progression. Study description: SERENA-6 is an ongoing, randomized, multicenter, double-blind, Phase III trial. Patients with HR+/HER2− mBC who have received at least 6 months of 1L AI (letrozole or anastrozole) + CDK4/6i (palbociclib or abemaciclib) and do not have clinical or radiological disease progression will be enrolled into Step 1, the ESR1m detection phase. During this phase, patients will be monitored regularly for the presence of ESR1m via central circulating tumor DNA analysis. Patients with detectable ESR1m and no overt disease progression (by RECIST v1.1 criteria) will be enrolled into Step 2 double-blind 1:1 randomization to either continue AI plus CDK4/6i, plus a placebo for AZD9833, or switch to AZD9833 (75 mg oral once daily), plus the same CDK4/6i plus a placebo for the AI. The primary endpoint will be investigator-assessed progression-free survival (PFS) per RECIST v1.1 criteria. A key secondary endpoint will be time to second progression or death on a subsequent therapy. Other secondary endpoints will include overall survival, chemotherapy-free survival, objective response rate, clinical benefit rate, patient-reported outcomes, and safety. Enrollment began in June 2021 and is expected at approximately 200 sites across 19 countries. Acknowledgments: We thank Julia Mawer, PhD, of Oxford PharmaGenesis, UK, for medical writing assistance, which was funded by AstraZeneca. Funding: The SERENA-6 trial is funded and overseen by AstraZeneca.

Citation Format: François-Clément Bidard, Kevin Kalinsky, Massimo Cristofanilli, Giampaolo Bianchini, Stephen KL Chia, Wolfgang Janni, Cynthia X Ma, Erica L Mayer, Yeon Hee Park, Steven Fox, Xiaochun Liu, Andrew Walding, Cynthia Huang Bartlett, Nick C Turner. SERENA-6: A Phase III study to assess the efficacy and safety of AZD9833 (camizestrant) compared with aromatase inhibitors when given in combination with palbociclib or abemaciclib in patients with HR+/HER2- metastatic breast cancer with detectable ESR1m who have not experienced disease progression on first-line therapy [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 OT2-11-05.

Abstract P4-09-01: Incidence of patient-reported fatigue developing in patients receiving palbociclib and endocrine therapy for advanced HR+ HER2- breast cancer

Background: Clinician-rated adverse event data from pivotal trials of the CDK4/6 inhibitor palbociclib (palbo) in patients (pts) with HR+ HER2- metastatic breast cancer (MBC) describe fatigue as a common non-hematologic toxicity. While palbo and endocrine therapy (ET) significantly improve outcomes compared to ET alone, in a pooled analysis of the PALOMA trials, rates of incident Common Terminology Criteria for Adverse Events (CTCAE) all-grade fatigue over 4.2 years of treatment approached 39.2%, with grade 3/4 at 2.5%. As these studies included only provider-rated CTCAE toxicity, it is important to quantify pts’ ratings of fatigue severity, which may differ from clinician assessments. Methods: Eligible pts with HR+ HER2- MBC, initiating standard-dose palbo with ET (aromatase inhibitor or fulvestrant), and without clinically meaningful fatigue prior to initiation of palbo, were followed for the 6 initial treatment cycles. The absence of baseline fatigue was established using the patient-reported Functional Assessment of Chronic Illness Therapy Fatigue Scale (FACIT-F), a 13-item scale (range 0-52, lower score = more fatigue) validated against anemia to indicate clinically meaningful fatigue if FACIT-F score &lt;34. After screening and baseline assessments (several weeks apart), the FACIT-F was repeated during the 3rd week of 6 consecutive cycles. Pts also reported fatigue severity using the NCI Patient-Reported Outcomes for CTCAE (PRO-CTCAE; range 0-4; grade 3/4 = severe) when they completed the FACIT-F. The primary endpoint was new-onset fatigue (FACIT-F score &lt;34) after treatment initiation; the secondary endpoint was severe fatigue on the PRO-CTCAE fatigue severity item. Incident rate of fatigue was estimated based on frequencies (dichotomized FACIT-F scores &lt;34 vs. &gt;=34; PRO-CTCAE fatigue severity grade 3/4 vs. &lt;3). Rate of fatigue incidence on the FACIT-F in the presence of competing risks (e.g., disease progression or study burden) was estimated using the cumulative incidence function. Concurrently rated FACIT-F scores were compared between PRO-CTCAE severe and non-severe cases using linear mixed-models. Results: Of 115 pts enrolled (5/2018-1/2021), 88 were evaluable after excluding those not initiating palbo (n=3), without baseline data (n=13), or with clinically meaningful fatigue between screening and baseline (n=11). Mean (±SD) age was 59.4 ± 11.3, baseline FACIT-fatigue score was 44.4 ± 5.1, and follow-up duration was 5.8 ± 2.0 cycles. The majority (72%) were receiving palbo with letrozole. New-onset fatigue through the 6th treatment cycle was observed in 21 pts, translating to a fatigue incidence rate of 23.9% (95% CI 15.4% - 34.1%). The mean time to new-onset fatigue was 3.8 ± 1.7 treatment cycles. Those who withdrew early (n=26) completed data for 3.7 ± 2.1 treatment cycles; the cumulative incidence of fatigue at 4 treatment cycles was 18.2% (95% CI 10.9 - 26.9). Using the PRO-CTCAE, the incidence rate of severe fatigue was 14.8% (95% CI 8.1% - 23.9%). The mean FACIT-F score when PRO-CTCAE grade indicated severe fatigue was significantly lower (more fatigue) than when the PRO-CTCAE grade was non-severe (26.3 ± 5.1 vs. 44.8 ± 4.8, p&lt;0.0001). Conclusion: In pts with HR+ HER2- MBC initiating palbo and ET, approximately one-quarter develop fatigue within the first 6 cycles based on the FACIT-F, which associates significantly with a PRO-CTCAE severity grade 3/4. While direct comparison cannot be made between provider-rated CTCAE and patient-reported PRO-CTCAE, it is notable that the incidence of severe fatigue with PRO-CTCAE is higher than that observed with provider-rated CTCAE. Ongoing analyses will explore potential associations of factors (e.g., hematological, sleep, activity) with treatment-emergent fatigue developing on palbo and ET therapy.

Citation Format: Shadab A Rahman, Erica L Mayer, Hanneke Poort, Deborah Schrag, Stephanie C Tung, Eric S Zhou, Aleta Wiley, Lauren Finkelstein, Elkhansaa Elguenaoui, Moira Nolan, Hadine Joffe. Incidence of patient-reported fatigue developing in patients receiving palbociclib and endocrine therapy for advanced HR+ HER2- 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 P4-09-01.

Abstract P4-10-02: Patient-reported outcomes in EA1131: A randomized phase III trial of platinum vs. capecitabine in patients with residual triple-negative breast cancer after neoadjuvant chemotherapy

Background: Understanding health-related quality of life (HRQOL), including side effects, is critical to guide supportive care during chemotherapy. The EA1131 trial demonstrated that Platinum (Plat) was unlikely to improve outcomes compared to capecitabine (Cape) in patients with stage II-III triple-negative breast cancer (TNBC) of basal subtype and ≥1 cm residual disease after neoadjuvant chemotherapy (NAC), supporting Cape as the continued standard of care. Patient-reported outcomes (PRO) were administered as a sub-study to understand HRQOL and symptoms from the patient’s perspective. Methods: EA1131 was amended in 9/2017 to add PRO endpoints and all patients enrolled after this amendment were eligible for the PRO sub-study. The Functional Assessment of Cancer Therapy-Breast Cancer Symptom Index (FBSI) and the Functional Assessment of Cancer Therapy/Gynecologic Oncology Group Neurotoxicity Subscale (NtxS; Plat arm only) were administered at baseline (BL), cycle 3 day 1 (C3D1), and following treatment at 6 and 15 months. Due to early trial termination, the PRO sub-study target accrual (n=362) was not reached. It was hypothesized that HRQOL, assessed by the FBSI-Treatment Side Effect (TSE) subscale (range 0-16, higher score = less side effects, better HRQOL), would indicate fewer post-treatment side effects at 6 and 15 months following Plat compared to Cape. The Wilcoxon rank sum test was used to compare FBSI-TSE subscale scores and total FBSI scores (range 0-64, higher score = better overall HRQOL) between arms at BL, C3D1, 6 months and 15 months. Two-sample t-tests were used to compare change in FBSI-TSE subscale scores and total FBSI scores from BL to C3D1 between arms. Change in NtxS scores (range 0-44, higher score = less neurotoxicity) from BL to C3D1 was evaluated with the paired t-test. Analyses were exploratory and p-values &lt;0.05 considered significant without multiple comparisons adjustment. Results: Of 331 patients eligible for the PRO sub-study (156 Plat arm, 175 Cape arm), 296 (89.4%) completed ≥1 PRO. Mean FBSI-TSE subscale scores were better for Cape at BL (Cape 14.5, Plat 13.9, p-value 0.02), for Plat at C3D1 (Cape 13.5, Plat 14.0, p-value 0.04), and did not differ at 6 months (Cape 14.6, Plat 14.7, p-value 0.70) or 15 months (Cape 14.9, Plat 14.5, p-value 0.44). FBSI-TSE subscale scores worsened from BL to C3D1 for Cape but not for Plat (mean change Cape -0.72, mean change Plat 0.15, p-value 0.003). FBSI-TSE subscale change scores from BL to C3D1 exceeded the threshold for clinically meaningful worsening (&gt; 1.5 points) in 27% of patients on Cape and 23% of patients on Plat (p-value 0.51). Mean total FBSI scores did not differ between arms at any time (BL: Cape 50.6, Plat 49.7; C3D1: Cape 48.1, Plat 48.0; 6 months: Cape 49.9, Plat 51.1; 15 months: Cape 53.3, Plat 50.3; all p &gt; 0.05). Mean change in total FBSI scores from BL to C3D1 did not differ between arms (Cape -2.20, Plat -1.83, p = 0.75). Mean (standard deviation) NtxS scores for the Plat arm were 38 (6.3), 36.1 (7.8), 36 (7.1) and 34.5 (7.9) at BL, C3D1, 6 months and 15 months, respectively. Mean NtxS score decreased (indicating worsening neurotoxicity) from BL to C3D1 (p-value 0.006). Conclusions: Despite more frequent severe toxicity by CTCAE criteria for Plat than Cape, patient-reported side effects worsened during treatment with Cape but not Plat. Overall, changes in HRQOL were small for both arms and resolved after therapy. However approximately one-fourth of patients had clinically meaningful worsening side effects on both arms. PRO-assessed neurotoxicity increased in the Plat arm. This PRO sub-study demonstrates that PROs capture toxicities beyond CTCAE criteria and provides novel data about patients’ experience during adjuvant chemotherapy following NAC for TNBC.

Citation Format: Karen L Smith, Fengmin Zhao, Ingrid A Mayer, Amye J Tevaarwerk, Sofia F Garcia, Carlos L Arteaga, William F Symmans, Ben H Park, Brian L Burnette, Della F Makower, Margaret Block, Kimberly A Morley, Chirag R Jani, Craig Mescher, Shabana J Dewani, Ursa Brown-Glaberman, Lisa E Flaum, Erica L Mayer, William M Sikov, Eve T Rodler, Angela M DeMichele, Joseph A Sparano, Antonio C Wolff, Kathy D Miller, Lynne I Wagner. Patient-reported outcomes in EA1131: A randomized phase III trial of platinum vs. capecitabine in patients with residual triple-negative breast cancer after neoadjuvant chemotherapy [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 P4-10-02.

Abstract GS1-07: Adjuvant palbociclib in HR+/HER2- early breast cancer: Final results from 5,760 patients in the randomized phase III PALLAS trial

Background Advances in the multidisciplinary care of hormone-receptor positive (HR+) early breast cancer (eBC) have markedly improved clinical outcomes: however, disease recurrence may still occur, particularly in patients (pts) with moderate or high-risk cancers at the time of diagnosis. The use of CDK4/6 inhibitors (CDK4/6i) combined with endocrine therapy (ET) is a standard of care for advanced breast cancer, supporting the rationale to study CDK4/6i in the eBC setting. Here we present the final protocol-planned analyses of the global phase III PALLAS trial investigating whether the addition of the CDK4/6i palbociclib (P) to adjuvant ET improves outcomes over ET alone for HR+/HER2- eBC. Methods PALLAS (PALbociclib CoLlaborative Adjuvant Study, NCT02513394) is a randomized phase III open-label trial in which pts with stage II-III HR+/HER2- eBC were randomized to receive either 2 years of P with adjuvant ET (P+ET) or ET alone. The primary endpoint is invasive disease-free survival (iDFS); secondary endpoints include distant recurrence-free survival (DRFS), locoregional recurrence-free survival (LRRFS), overall survival (OS), and safety. Mandatory biospecimen collection has supported the creation of an expansive translational science program, and long-term follow-up is planned. Revised sample size calculations required recruitment of 5600 pts in order to detect a 25% iDFS improvement in patients receiving P+ET with 85% power; this final protocol-planned analysis was planned after 469 iDFS events. Results From September 1, 2015 to November 30, 2018, 5,761 pts (median age 52 years, range 22-90) were randomized in 406 centers in 21 countries worldwide. 1,014 (17.6%) had stage IIA disease (capped) and 4,728 (82.1%) stages IIB/III. 4,754 (82.5%) had received prior (neo)adjuvant chemotherapy. After a protocol-planned 2nd interim analysis in May 2020 crossed the futility threshold, 349 P+ET pts still on active treatment stopped P and were transferred to follow-up. At the time of final analysis cutoff date (November 20, 2020), after a median follow-up of 31 months and 516 events recorded, iDFS was similar between the two arms, with 3-year iDFS of 89.3% (95% CI: 87.8-90.6%) for Palbo+ET, and 89.4% (88.0-90.7%) for ET alone (hazard ratio 0.96, 95% CI: 0.81-1.14). There was no statistically significant difference in secondary outcome endpoints. Subgroup analyses revealed no significant interactions between treatment effect and other factors (including risk category). The safety profile of P was as expected, with grade 3 or 4 neutropenia the most common side effect (safety population: 1759/2841 [61.9%] vs 11/2902 [0.4%]). Overall 42% of pts. discontinued P prior to the planned 2-year duration, 28.2% of Palbo+ET pts discontinued therapy due to adverse events, without an observed impact on survival outcomes. Conclusions Now with the full number of events, this analysis of the PALLAS trial shows that the addition of 2 years of P to ongoing adjuvant ET did not improve survival endpoints for pts with stage II-III HR+/HER2- eBC. Whether P is beneficial in the adjuvant setting for certain sub-groups of pts will be further evaluated with longer-term follow-up and by the ongoing translational science program. Support: ABCSG; AFT; Pfizer; ClinicalTrials.gov Identifier: NCT02513394; https://www.abcsg.org; https://acknowledgments.alliancefound.org

Citation Format: Michael Gnant, Amylou C Dueck, Sophie Frantal, Miguel Martin, Hal Burstein, Richard Greil, Peter Fox, Antonio C Wolff, Arlene Chan, Eric Winer, Christian Singer, Kathy Miller, Marco Colleoni, Michelle Naughton, Gabor Rubovszky, Judith Bliss, Ingrid A Mayer, Guenther G Steger, Zbigniew Nowecki, Olwen Hahn, Norman Wolmark, Hope Rugo, Georg Pfeiler, Hannes Fohler, Otto Metzger, Céline Schurmans, Kathy P Theall, Dongrui R Lu, Kathleen Tenner, Christian Fesl, Angela DeMichele*, Erica L Mayer, *shared last authorship. Adjuvant palbociclib in HR+/HER2- early breast cancer: Final results from 5,760 patients in the randomized phase III PALLAS trial [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 GS1-07.

Phase 1b Clinical Trial with Alpelisib plus Olaparib for Patients with Advanced Triple-Negative Breast Cancer

PURPOSE

We had previously reported on the safety and the recommended phase 2 dose (RP2D) of olaparib in combination with the PI3Kα-specific inhibitor alpelisib in patients with high-grade serous ovarian cancer as studied in a phase 1b trial (NCT01623349). Here we report on the breast cancer cohort from that study.

EXPERIMENTAL DESIGN

Eligible patients had recurrent triple-negative breast cancer (TNBC), or recurrent breast cancer of any subtype with a germline BRCA mutation and were enrolled to a dose escalation or expansion cohort. After definition of the RP2D, secondary end points included safety and objective response rate (ORR). Exploratory analyses were performed using circulating free DNA (cfDNA).

RESULTS

17 patients with TNBC were enrolled with a median of 3 prior lines of chemotherapy. The most common treatment-related grade 3-4 adverse events were hyperglycemia (18%) and rash (12%). The ORR was 18% (23% for patients treated at the RP2D) and 59% had disease control. The median duration of response was 7.4 months. Analysis of cfDNA tumor fractions (TFx) revealed that patients with TFx<15% after completion of the first cycle had a longer progression-free survival compared to those with TFx>15% (6.0 months vs 0.9 months, p=0.0001).

CONCLUSIONS

Alpelisib in combination with olaparib is tolerable in patients with pre-treated TNBC, with evidence of activity in non-BRCA carriers. CfDNA provided important prognostic information. Results highlight potential synergistic use of a PI3Ki to sensitize HR-proficient (BRCA wild-type) TNBC to PARPi and suggest the potential to expand the use of PARPi beyond BRCA-mutant tumors.

Treatment Exposure and Discontinuation in the PALbociclib CoLlaborative Adjuvant Study of Palbociclib With Adjuvant Endocrine Therapy for Hormone Receptor-Positive/Human Epidermal Growth Factor Receptor 2-Negative Early Breast Cancer (PALLAS/AFT-05/ABCSG-42/BIG-14-03)

PURPOSE

The PALLAS study investigated whether the addition of palbociclib, an oral CDK4/6 inhibitor, to adjuvant endocrine therapy (ET) improves invasive disease-free survival (iDFS) in early hormone receptor-positive (HR+), human epidermal growth factor receptor 2-negative (HER2-) breast cancer. In this analysis, we evaluated palbociclib exposure and discontinuation in PALLAS.

METHODS

Patients with stage II-III HR+, HER2- disease were randomly assigned to 2 years of palbociclib with adjuvant ET versus ET alone. The primary objective was to compare iDFS between arms. Continuous monitoring of toxicity, dose modifications, and early discontinuation was performed. Association of baseline covariates with time to palbociclib reduction and discontinuation was analyzed with multivariable competing risk models. Landmark and inverse probability weighted per-protocol analyses were performed to assess the impact of drug persistence and exposure on iDFS.

RESULTS

Of the 5,743 patient analysis population (2,840 initiating palbociclib), 1,199 (42.2%) stopped palbociclib before 2 years, the majority (772, 27.2%) for adverse effects, most commonly neutropenia and fatigue. Discontinuation of ET did not differ between arms. Discontinuations for non-protocol-defined reasons were greater in the first 3 months of palbociclib, and in the first calendar year of accrual, and declined over time. No significant relationship was seen between longer palbociclib duration or ≥ 70% exposure intensity and improved iDFS. In the weighted per-protocol analysis, no improvement in iDFS was observed in patients receiving palbociclib versus not (hazard ratio 0.89; 95% CI, 0.72 to 1.11).

CONCLUSION

Despite observed rates of discontinuation in PALLAS, analyses suggest that the lack of significant iDFS difference between arms was not directly related to inadequate palbociclib exposure. However, the discontinuation rate illustrates the challenge of introducing novel adjuvant treatments, and the need for interventions to improve persistence with oral cancer therapies.

The effects of a clinic-based weight loss program on health-related quality of life and weight maintenance in cancer survivors: A randomized controlled trial

OBJECTIVE

The Healthy Living and Eating After Cancer Trial demonstrated that a clinic-based weight loss program reduced body weight, as compared with a waitlist control group, over 15 weeks. Here we report the impact of the weight loss intervention on health-related quality-of-life outcomes at week 15, and maintenance of weight loss to week 30.

METHODS

This trial randomized cancer survivors of solid tumors and hematologic malignancies (breast cancer: 76.7%) to a 15-week group-based weight loss program (n = 30) or a waitlist control group (n = 30). Participants were not blinded to group assignment. Participants completed a variety of health-related quality-of-life outcome measures at baseline and week 15. From week 15 to week 30, participants initially randomized to the weight loss program were followed with no additional intervention, and participants initially randomized to the waitlist control group commenced the weight loss program.

RESULTS

Over the 15 weeks, the weight loss program improved physical functioning (6.2 ± 2.9; p = 0.02; d = 0.31) and reduced insomnia symptoms (-17.1 ± 7.4; p = 0.03; d = -0.30) as measured by the EORTC QLQ-C30, and sleep disturbance (-4.9 ± 1.6; p = 0.005; d = -0.40) as measured by PROMIS, compared to waitlist control. After a weight loss of 4.6 ± 3.9 kg, from week 15 to week 30, participants who were initially randomized to the weight loss program maintained their prior weight loss (+0.6 ± 3.5 kg) and participants who were initially randomized to the waitlist control group lost weight (-3.4 ± 2.9 kg; p < 0.001).

CONCLUSIONS

In cancer survivors with overweight or obesity, a 15-week clinic-based weight loss program improved health-related quality-of-life outcomes and produced sustained weight loss to week 30.

Adjuvant Palbociclib for Early Breast Cancer: The PALLAS Trial Results (ABCSG-42/AFT-05/BIG-14-03)

PURPOSE

Palbociclib is a cyclin-dependent kinase 4 and 6 inhibitor approved for advanced breast cancer. In the adjuvant setting, the potential value of adding palbociclib to endocrine therapy for hormone receptor-positive breast cancer has not been confirmed.

PATIENTS AND METHODS

In the prospective, randomized, phase III PALLAS trial, patients with hormone receptor-positive, human epidermal growth factor receptor 2-negative early breast cancer were randomly assigned to receive 2 years of palbociclib (125 mg orally once daily, days 1-21 of a 28-day cycle) with adjuvant endocrine therapy or adjuvant endocrine therapy alone (for at least 5 years). The primary end point of the study was invasive disease-free survival (iDFS); secondary end points were invasive breast cancer-free survival, distant recurrence-free survival, locoregional cancer-free survival, and overall survival.

RESULTS

Among 5,796 patients enrolled at 406 centers in 21 countries worldwide over 3 years, 5,761 were included in the intention-to-treat population. At the final protocol-defined analysis, at a median follow-up of 31 months, iDFS events occurred in 253 of 2,884 (8.8%) patients who received palbociclib plus endocrine therapy and in 263 of 2,877 (9.1%) patients who received endocrine therapy alone, with similar results between the two treatment groups (iDFS at 4 years: 84.2% v 84.5%; hazard ratio, 0.96; CI, 0.81 to 1.14; P = .65). No significant differences were observed for secondary time-to-event end points, and subgroup analyses did not show any differences by subgroup. There were no new safety signals for palbociclib in this trial.

CONCLUSION

At this final analysis of the PALLAS trial, the addition of adjuvant palbociclib to standard endocrine therapy did not improve outcomes over endocrine therapy alone in patients with early hormone receptor-positive breast cancer.

Do you mind if I record?: Perceptions and practice regarding patient requests to record clinic visits in oncology

BACKGROUND

Audio recordings of oncology clinic discussions can help patients retain and understand information about their disease and treatment decisions. Access to this tool relies on acceptance of recordings by oncologists. This is the first study to evaluate experience and attitudes of oncologists toward patients recording clinic visits.

METHODS

Medical, radiation, and surgical oncologists from 5 US cancer centers and community affiliates were surveyed to evaluate clinicians' experience, beliefs, and practices regarding patient-initiated recordings.

RESULTS

Among 360 oncologists (69% response rate), virtually all (93%) have experienced patients seeking to record visits. Although 75% are comfortable with recording, 25% are uncomfortable and 56% report concerns ranging from less thorough discussions to legal liability. Most (85%) always agree when patients ask to record, but 15% never or selectively allow recording. Although 51% believe recording is positive for the patient-physician relationship, a sizable minority report that it can lead to less detailed conversations (28%) or avoidance of difficult topics, including prognosis (33%). Views did not vary based on subspecialty, practice setting, or geographic region, but older age and years in practice were associated with more positive views of recording. The majority of clinicians (72%) desire institutional policies to govern guidelines about recordings.

CONCLUSIONS

Most oncologists are comfortable with patient requests to record visits, but a sizable minority remain uncomfortable, and access to recording varies solely on physician preference. This difference in care delivery may benefit from institutional policies that promote access while addressing legitimate physician concerns over privacy and appropriate use of recordings.

Multidisciplinary Recommendations Regarding Post-Vaccine Adenopathy and Radiologic Imaging: Radiology Scientific Expert Panel

Vaccination-associated adenopathy is a frequent imaging finding after administration of COVID-19 vaccines that may lead to a diagnostic conundrum in patients with manifest or suspected cancer, in whom it may be indistinguishable from malignant nodal involvement. To help the medical community address this concern in the absence of studies and evidence-based guidelines, this special report offers recommendations developed by a multidisciplinary panel of experts from three of the leading tertiary care cancer centers in the United States. According to these recommendations, some routine imaging examinations, such as those for screening, should be scheduled before or at least 6 weeks after the final vaccination dose to allow for any reactive adenopathy to resolve. However, there should be no delay of other clinically indicated imaging (eg, for acute symptoms, short-interval treatment monitoring, urgent treatment planning or complications) due to prior vaccination. The vaccine should be administered on the side contralateral to the primary or suspected cancer, and both doses should be administered in the same arm. Vaccination information-date(s) administered, injection site(s), laterality, and type of vaccine-should be included in every preimaging patient questionnaire, and this information should be made readily available to interpreting radiologists. Clear and effective communication between patients, radiologists, referring physician teams, and the general public should be considered of the highest priority when managing adenopathy in the setting of COVID-19 vaccination.