Poznak, Catherine Van

PURPOSE Long-term outcomes of patients with stage I human epidermal growth factor receptor 2 (HER2)–positive breast cancer receiving adjuvant trastuzumab emtansine (T-DM1) remain undefined, and prognostic predictors represent an unmet need. METHODS In the ATEMPT phase II trial, patients with stage I centrally confirmed HER2-positive breast cancer were randomly assigned 3:1 to adjuvant T-DM1 for 1 year or paclitaxel plus trastuzumab (TH). Coprimary objectives were to compare the incidence of clinically relevant toxicities between arms and to evaluate invasive disease-free survival (iDFS) with T-DM1. Correlative analyses included the HER2DX genomic tool, multiomic evaluations of HER2 heterogeneity, and predictors of thrombocytopenia. RESULTS After a median follow-up of 5.8 years, 11 iDFS events were observed in the T-DM1 arm, consistent with a 5-year iDFS of 97.0% (95% CI, 95.2 to 98.7). At 5 years, the recurrence-free interval (RFI) was 98.3% (95% CI, 97.0 to 99.7), the overall survival was 97.8% (95% CI, 96.3 to 99.3), and the breast cancer-specific survival was 99.4% (95% CI, 98.6 to 100). Comparable iDFS was observed with T-DM1 irrespective of tumor size, hormone receptor status, centrally determined HER2 immunohistochemical score, and receipt of T-DM1 for more or less than 6 months. Although ATEMPT was not powered for this end point, the 5-year iDFS in the TH arm was 91.1%. Among patients with sufficient tissue for HER2DX testing (n = 187), 5-year outcomes significantly differed according to HER2DX risk score, with better RFI (98.1% v 81.8%, hazard ratio [HR], 0.10, P = .01) and iDFS (96.3% v 81.8%, HR, 0.20, P = .047) among patients with HER2DX low-risk versus high-risk tumors, respectively. CONCLUSION Adjuvant T-DM1 for 1 year leads to outstanding long-term outcomes for patients with stage I HER2-positive breast cancer. A high HER2DX risk score predicted a higher risk of recurrence in ATEMPT.

Abstract Introduction Prospective data about quality of life (QoL) in men with breast cancer (BC) are lacking. A prospective registry (EORTC10085) of men with all BC stages, including a QoL correlative study, was performed as part of the International Male Breast Cancer Program. Methods Questionnaires at BC diagnosis included the EORTC QLQ-C30 and BR23 (BC specific module), adapted for men. High functioning and global health/QoL scores indicate high functioning levels/high QoL; high symptom-focused measures scores indicate high symptoms/problems levels. EORTC reference data for healthy men and women with BC were used for comparisons. Results Of 422 men consenting to participate, 363 were evaluable. Median age was 67 years, and median time between diagnosis and survey was 1.1 months. A total of 114 men (45%) had node-positive early disease, and 28 (8%) had advanced disease. Baseline mean global health status score was 73 (SD: 21), better than in female BC reference data (62, SD: 25). Common symptoms in male BC were fatigue (22, SD: 24), insomnia (21, SD: 28), and pain (16, SD: 23), for which women’s mean scores indicated more burdensome symptoms at 33 (SD: 26), 30 (SD: 32), and 29 (SD: 29). Men’s mean sexual activity score was 31 (SD: 26), with less sexual activity in older patients or advanced disease. Conclusions QoL and symptom burden in male BC patients appears no worse (and possibly better) than that in female patients. Future analyses on impact of treatment on symptoms and QoL over time, may support tailoring of male BC management.

Abstract Background: The ATEMPT trial primary analysis found that one year of adjuvant trastuzumab emtansine (T-DM1) achieved a 3-year iDFS of 97.8% for patients with stage I HER2+ breast cancer, but was not associated with fewer clinically relevant toxicities (CRTs) compared with paclitaxel and trastuzumab (TH). In this end-of-study analysis, we report 5-year survival outcomes and correlative analyses from the trial. Methods: Patients with stage I centrally confirmed HER2+ breast cancer were randomly assigned 3:1 to adjuvant T-DM1 for one year or TH and received T-DM1 3.6 mg/kg IV every 3 weeks for 17 cycles or paclitaxel 80 mg/m2 IV with weekly trastuzumab IV followed by trastuzumab for 9 months. The co-primary objectives were to compare the incidence of CRTs between the 2 arms and to evaluate iDFS in patients receiving T-DM1. To investigate proteomic correlates of recurrence, spatial proteomic analyses were performed on samples from 13 patients experiencing iDFS events (cases) and 24 matched controls using the NanoString GeoMx Digital Spatial Profiler. The impact of HER2 heterogeneity on outcomes was investigated among 17 cases and 51 matched controls by fluorescence in-situ hybridization (FISH). HER2 genetic heterogeneity was assessed by scrutinizing the whole tumor area and defined as the occurrence of HER2 gene amplification in >5% but < 50% invasive tumor cells. The risk of recurrence was evaluated centrally with the HER2DX genomic assay from 225 primary tumor samples. Germline whole genome sequencing (WGS) was conducted among 55 patients experiencing T-DM1-induced thrombocytopenia and/or bleeding and 55 matched controls to identify genomic correlates for this side effect. Results: A total of 497 patients who initiated protocol therapy were included in this analysis (383 T-DM1 and 114 TH). After a median follow up 5.8 years, among patients receiving T-DM1 there were a total of 11 iDFS events, with 3 distant recurrences. The 5-year iDFS for T-DM1 was 97.0% (95% CI, 95.3-98.8%), the 5-year recurrence-free interval (RFI) was 98.6% (95% CI: 97.4-99.8%) and the 5-year overall survival (OS) for T-DM1 was 97.8 % (95% CI, 96.3-99.3%). Although the study was not powered to evaluate the efficacy of TH, among the 114 patients receiving TH, a total of 9 iDFS events were observed, including 2 distant events; the 5-year iDFS with TH was 91.3% (95% CI: 86.0-96.9%), 5-year RFI was 93.3% (95% CI: 88.6-98.2%) and 5-year OS was 97.9% (95% CI: 95.2-100%). A total of 56 samples were evaluable for heterogeneity analyses, among which 14% (n=8) harbored HER2 genetic heterogeneity. Spatial proteomic analyses found that NF1 (adjusted p=0.72 × 10-6) and CTLA-4 (adjusted p=0.15 × 10-3) were significantly upregulated in primary samples from cases, while cleaved caspase 9, CD25, GITR, ICOS, p53 and PD-L2 were significantly upregulated in controls (all with adjusted p< 0.05). Germline WGS found that the top gene associations with thrombocytopenia and thrombocytopenia or bleeding were ALMS1 (p=0,19 × 10-3) and APBA3 (p=0,23 × 10-3), respectively, although none reaching the threshold for genome wide significance. rs62143195 and rs114169776 were the top single nucleotide polymorphisms associated with thrombocytopenia and thrombocytopenia or bleeding, respectively. Data on the impact of HER2 heterogeneity and of HER2DX score on survival outcomes will be presented. Conclusion: With longer follow-up, adjuvant T-DM1 confirmed outstanding long-term outcomes among patients with stage I HER2+ breast cancer, demonstrating a 5-year RFI of 98.6%. Spatial proteomic analyses identified a potential association between NF1 and CTLA-4 expression with recurrence. Details on the impact of HER2 heterogeneity and HER2DX assay on prognosis will be presented. Citation Format: Paolo Tarantino, Nabihah Tayob, Chau T Dang, Denise Yardley, Steven J. Isakoff, Vicente Valero, Meredith Faggen, Therese Mulvey, Ron Bose, Douglas Weckstein, Antonio C. Wolff, Katherine Reeder-Hayes, Hope Rugo, Bhuvaneswari Ramaswamy, Dan Zuckerman, Lowell Hart, Vijayakrishna K. Gadi, Michael Constantine, Kit Cheng, Audrey Merrill Garrett, Paul K. Marcom, Kathy S. Albain, Patricia DeFusco, Nadine Tung, Blair Ardman, Rita Nanda, Rachel C. Jankowitz, Mothaffar Rimawi, Vandana Abramson, Paula R. Pohlmann, Catherine Van Poznak, Andres Forero-Torres, Minetta C. Liu, Kathryn Ruddy, Yue Zheng, Romualdo Barroso-Sousa, Adrienne Waks, Michelle K. DeMeo, Molly K. DiLullo, Giuseppe Curigliano, Harold Burstein, Ann Partridge, Eric Winer, Giuseppe Viale, Winnie Hui, Elizabeth A. Mittendorf, Bryan P. Schneider, Aleix Prat, Ian Krop, Sara Tolaney. Adjuvant Trastuzumab Emtansine Versus Paclitaxel plus Trastuzumab for Stage I HER2+ Breast Cancer: 5-year results and correlative analyses from ATEMPT (TBCRC033) [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 PD18-01.

Abstract PURPOSE: Treatment options for patients (pts) with HER2+ BCBM remain limited. We previously reported that neratinib monotherapy is associated with a volumetric central nervous system objective response rate (CNS ORR) of 8%, whereas the combination of neratinib and capecitabine resulted in a volumetric CNS ORR of 49% (in lapatinib-naïve pts). Preclinical data suggest that neratinib may overcome resistance to trastuzumab-emtansine (T-DM1) and that the combination has potential CNS efficacy. Here, we report results of neratinib plus T-DM1 in pts with HER2+ BCBM. PATIENTS AND METHODS: In this prospective, multicenter, phase II study, pts with measurable HER2+ BCBM received neratinib 160 mg orally once daily plus T-DM1 3.6 mg/kg IV every 21 days in three parallel-enrolling cohorts. Cohort 4A enrolled pts with previously untreated brain metastases. Cohort 4B enrolled pts with BCBM progressing after prior local CNS-directed therapy without prior exposure to T-DM1. Cohort 4C enrolled pts with BCBM progressing after prior local CNS-directed therapy who had previous exposure to T-DM1. Diarrhea prophylaxis with colestipol and loperamide was required during cycle 1. Cohorts 4A and 4B were single-stage with a planned enrollment of 20 patients; cohort 4C had a two-stage design, with a requirement for at least 1 of the first 9 pts to achieve a response in order to enroll a total of 24 patients. The primary endpoint was Response Assessment in Neuro-Oncology-Brain Metastases (RANO BM) in each cohort separately. Correlative studies included patient-reported outcomes (PROs) for gastrointestinal toxicity. RESULTS: We enrolled 6, 17, and 21 patients to cohorts 4A, 4B, and 4C, during 11/07/2018 – 11/01/2021. Enrollment was stopped prematurely due to slow accrual. Across Cohorts 4A-4C, the median number of prior lines of chemotherapy prior to enrollment was 2 (range 1-10); 25% received prior lapatinib and no patients received prior tucatinib. In cohorts 4B and 4C (prior CNS-treated cohorts), 33% had prior CNS surgery and >94% had prior CNS radiation. Among evaluable patients, CNS ORR in cohorts 4A (n=6), 4B (n=16), and 4C (n=21) was 50.0% (95% CI 18.8- 81.2%), 25.0% (95% CI 8.3-52.6%), and 38.1% (95% CI 19.0-61.3%), respectively. Median (range) number of cycles completed for 4A, 4B, and 4C was 4.5 (1-15), 4 (range 0-49+), and 6 (0-23); three patients on Cohort 4B remain on protocol therapy (cycles 14, 45, and 49). The overall survival at 12-months for cohorts 4A, 4B, and 4C was 83.3% (95% CI, 58.3-100%), 86.2% (95% CI 70-100%), and 83.3% (95% CI 67.6-100%). Diarrhea was the most common grade 3 toxicity (19.0–33.3% across cohorts); one grade 4 liver function event occurred in cohort 4B. Updated efficacy results will be reported at the meeting; PRO analyses are ongoing. CONCLUSION: Intracranial activity was observed for the combination of neratinib plus T-DM1 across all three enrolled cohorts, including those with prior T-DM1 exposure, suggesting synergistic effects of this treatment combination. Our data provide additional evidence for consideration of neratinib-based combinations in pts with HER2+ BCBM. Citation Format: Rachel Freedman, Siyang Ren, Nabihah Tayob, Rebecca Gelman, Karen L. Smith, Raechel Davis, Alyssa Pereslete, Victoria Attaya, Christine Cotter, Wendy Y. Chen, Cesar Augusto Santa-Maria, Catherine Van Poznak, Beverly Moy, Adam M. Brufsky, Michelle Melisko, Ciara C. O’Sullivan, Nadia Ashai, Yasmeen Rauf, Julie Nangia, Dario Trapani, Jennifer Savoie, Robyn Burns, Antonio C. Wolff, Eric Winer, Mothaffar Rimawi, Ian Krop, Nancy U. Lin. Translational Breast Cancer Research Consortium Trial 022: Neratinib and Trastuzumab-Emtansine for HER2+ Breast Cancer Brain Metastases (BCBM) [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 PD7-03.

Abstract Background Hypercalcemia of malignancy (HCM) is the most common metabolic complication of malignancies, but its incidence may be declining due to potent chemotherapeutic agents. The high mortality associated with HCM has declined markedly due to the introduction of increasingly effective chemotherapeutic drugs. Despite the widespread availability of efficacious medications to treat HCM, evidence-based recommendations to manage this debilitating condition are lacking. Objective To develop guidelines for the treatment of adults with HCM. Methods A multidisciplinary panel of clinical experts, together with experts in systematic literature review, identified and prioritized 8 clinical questions related to the treatment of HCM in adult patients. The systematic reviews (SRs) queried electronic databases for studies relevant to the selected questions. The Grading of Recommendations Assessment, Development and Evaluation (GRADE) methodology was used to assess the certainty of evidence and make recommendations. An independent SR was conducted in parallel to assess patients' and physicians' values and preferences, costs, resources needed, acceptability, feasibility, equity, and other domains relevant to the Evidence-to-Decision framework as well as to enable judgements and recommendations. Results The panel recommends (strong recommendation) in adults with HCM treatment with denosumab (Dmab) or an intravenous (IV) bisphosphonate (BP). The following recommendations were based on low certainty of the evidence. The panel suggests (conditional recommendation) (1) in adults with HCM, the use of Dmab rather than an IV BP; (2) in adults with severe HCM, a combination of calcitonin and an IV BP or Dmab therapy as initial treatment; and (3) in adults with refractory/recurrent HCM despite treatment with BP, the use of Dmab. The panel suggests (conditional recommendation) the addition of an IV BP or Dmab in adult patients with hypercalcemia due to tumors associated with high calcitriol levels who are already receiving glucocorticoid therapy but continue to have severe or symptomatic HCM. The panel suggests (conditional recommendation) in adult patients with hypercalcemia due to parathyroid carcinoma, treatment with either a calcimimetic or an antiresorptive (IV BP or Dmab). The panel judges the treatments as probably accessible and feasible for most recommendations but noted variability in costs, resources required, and their impact on equity. Conclusions The panel's recommendations are based on currently available evidence considering the most important outcomes in HCM to patients and key stakeholders. Treatment of the primary malignancy is instrumental for controlling hypercalcemia and preventing its recurrence. The recommendations provide a framework for the medical management of adults with HCM and incorporate important decisional and contextual factors. The guidelines underscore current knowledge gaps that can be used to establish future research agendas.

PURPOSE The ATEMPT trial was designed to determine if treatment with trastuzumab emtansine (T-DM1) caused less toxicity than paclitaxel plus trastuzumab (TH) and yielded clinically acceptable invasive disease-free survival (iDFS) among patients with stage I human epidermal growth factor receptor 2–positive (HER2+) breast cancer (BC). METHODS Patients with stage I centrally confirmed HER2+ BC were randomly assigned 3:1 to T-DM1 or TH and received T-DM1 3.6 mg/kg IV every 3 weeks for 17 cycles or T 80 mg/m 2 IV with H once every week × 12 weeks (4 mg/kg load →2 mg/kg), followed by H × 39 weeks (6 mg/kg once every 3 weeks). The co-primary objectives were to compare the incidence of clinically relevant toxicities (CRTs) in patients treated with T-DM1 versus TH and to evaluate iDFS in patients receiving T-DM1. RESULTS The analysis population includes all 497 patients who initiated protocol therapy (383 T-DM1 and 114 TH). CRTs were experienced by 46% of patients on T-DM1 and 47% of patients on TH ( P = .83). The 3-year iDFS for T-DM1 was 97.8% (95% CI, 96.3 to 99.3), which rejected the null hypothesis ( P < .0001). Serially collected patient-reported outcomes indicated that patients treated with T-DM1 had less neuropathy and alopecia and better work productivity compared with patients on TH. CONCLUSION Among patients with stage I HER2+ BC, one year of adjuvant T-DM1 was associated with excellent 3-year iDFS, but was not associated with fewer CRT compared with TH.

1052 Background: TIG, an agonistic anti-DR5 monoclonal antibody, triggers apoptosis in DR5+ human tumor cells without the aid of crosslinking. TIG has shown strong in vitro and in vivo activity against basal-like breast cancer cells that is enhanced by chemotherapy like paclitaxel. Methods: Randomized 2:1 phase II trial of nab-PAC with/without TIG in TNBC patients. Patients stratified by prior exposure to chemotherapy in the metastatic setting. Patients received nab-PAC weekly x 3 and TIG every other week, every 28 days. Primary endpoint was overall response rate (ORR). Secondary objectives were safety, progression free survival (PFS), TIG immunogenicity, and PK. Biopsies and circulating tumor cells were collected. The trial was not powered to compare arms but allowed early stopping for futility and was sized to estimate ORR with 95% CI. Results: 64 patients enrolled, 60 treated; 39 in the combination arm and 21 in the nab-PAC arm. Of the 39 in the combination arm, there were 2 CR, 9 PR (1 near CR, 96% tumor reduction), 11 SD and 17 PD; ORR 28% (95% CI 14%-42%). Of the 21 in the single agent arm, there were no CR, 8 PR, 4 SD and 9 PD; ORR 38% (95% CI 17%-59%). Higher ORRs were seen in the chemotherapy naïve patients (58% vs. 15% combination and 42% vs. 35% single agent). 2 patients with CR, 1 near CR, and 1 PR in the combination arm are still on therapy (602+, 531+, 466+, 460+ days). PFS was similar in both groups (3.6 months); higher in chemotherapy naïve patients. Combination was well tolerated (most toxicities grade 1/2); the most common AEs were fatigue, alopecia, peripheral sensory neuropathy, anemia, neutropenia, nausea, thrombocytopenia, anorexia, diarrhea, and vomiting. No grade 4 or 5 toxicity. No apparent added toxicity with TIG was seen. Conclusions: Combination therapy with nab-PAC + TIG was well tolerated, without apparent improvement in ORR relative to nab-PAC alone; however, 4 subjects treated as first-line had prolonged clinical benefit with the combination, and correlative studies will investigate markers that might predict clinical outcome (Next-Gen genomic analysis). Clinical trial information: F101004001.

507 Background: The 21-gene Recurrence Score (OncotypeDX Breast Cancer Assay) predicts outcome and benefit from chemotherapy (CT) in early stage ER+ BC treated with adjuvant endocrine therapy. We evaluated the association between Recurrence Score (RS), time to progression (TTP), and overall survival (OS) in patients with stage IV BC enrolled in TBCRC 013. Methods: TBCRC 013 is a registry study evaluating surgery of the primary tumor in pts presenting with Stage IV BC. From 7/09 - 4/12, 128 evaluable pts were enrolled in two cohorts (A: metastases (mets) with intact primary tumor (n=112); B: mets within 3 months of primary surgery (n=16)). This study includes 110 pts with pre-treatment primary tumor samples available for analysis. Clinical variables, TTP and OS were correlated with RS using long-rank, Kaplan-Meier and Cox regression. Results: Median pt age was 52yrs (21-79) and median tumor size 3.1cm (0.7-15). 82 (80%) were ER+, 83 (81%) Her2(-) and 51 (46%) had bone-only mets. Cohorts A and B did not differ. At a median follow-up of 26 mos (1-47), median TTP is 19 mos (95%CI16-25) and surgery is not associated with OS. 102 samples qualified for RS. 23 (23%) had low RS<18, 29 (28%) intermediate RS, 18-30; and 50 (49%) high RS≥31. Age, tumor size or site of 1stmets was not associated with RS. Risk groups were prognostic for TTP in ER+ pts and for 2 yr OS in ER+Her2- pts (Table). In Cox models continuous RS was also prognostic for TTP in ER+ pts (HR 3.5; for 50 point difference (PD) 95%CI 1.5-8.1, p=0.003) and for OS in ER+Her2- pts (HR 21.4, for 50 PD 95%CI 2.2-204.4, p=0.008). In MVA, adjusting for clinical variables, RS remained prognostic for TTP in ER+ pts (p=0.01). Further analysis of surgery in this trial is ongoing. Conclusions: The 21-gene RS is independently prognostic for TTP in ER+ Stage IV BC. RS is also prognostic for OS in ER+Her2- BC, suggesting that a high RS may be a surrogate for endocrine resistance and could be used to select pts with ER+ Stage IV BC for CT. A randomized trial to address this hypothesis is warranted. Clinical trial information: NCT00941759. [Table: see text]

PURPOSE To develop recommendations concerning the management of male breast cancer. METHODS ASCO convened an Expert Panel to develop recommendations based on a systematic review and a formal consensus process. RESULTS Twenty-six descriptive reports or observational studies met eligibility criteria and formed the evidentiary basis for the recommendations. RECOMMENDATIONS Many of the management approaches used for men with breast cancer are like those used for women. Men with hormone receptor–positive breast cancer who are candidates for adjuvant endocrine therapy should be offered tamoxifen for an initial duration of five years; those with a contraindication to tamoxifen may be offered a gonadotropin-releasing hormone agonist/antagonist plus aromatase inhibitor. Men who have completed five years of tamoxifen, have tolerated therapy, and still have a high risk of recurrence may be offered an additional five years of therapy. Men with early-stage disease should not be treated with bone-modifying agents to prevent recurrence, but could still receive these agents to prevent or treat osteoporosis. Men with advanced or metastatic disease should be offered endocrine therapy as first-line therapy, except in cases of visceral crisis or rapidly progressive disease. Targeted systemic therapy may be used to treat advanced or metastatic cancer using the same indications and combinations offered to women. Ipsilateral annual mammogram should be offered to men with a history of breast cancer treated with lumpectomy regardless of genetic predisposition; contralateral annual mammogram may be offered to men with a history of breast cancer and a genetic predisposing mutation. Breast magnetic resonance imaging is not recommended routinely. Genetic counseling and germline genetic testing of cancer predisposition genes should be offered to all men with breast cancer.

AimsChemotherapy‐induced peripheral neuropathy (PN) is a treatment limiting toxicity of paclitaxel. We evaluated if EPHA genetic variation (EPHA4, EPHA5, EPHA6, and EPHA8) is associated with PN sensitivity by accounting for variability in systemic paclitaxel exposure (time above threshold).MethodsGermline DNA from 60 patients with breast cancer was sequenced. PN was measured using the 8‐item sensory subscale (CIPN8) of the patient‐reported CIPN20. Associations for 3 genetic models were tested by incorporating genetics into previously published PN prediction models integrating measured paclitaxel exposure and cumulative treatment. Significant associations were then tested for association with PN‐related treatment disruption.ResultsEPHA5 rs7349683 (minor allele frequency = 0.32) was associated with increased PN sensitivity (β‐coefficient = 0.39, 95% confidence interval 0.11–0.67, p = 0.007). Setting a maximum tolerable threshold of CIPN8 = 30, optimal paclitaxel exposure target is shorter for rs7349683 homozygous (11.6 h) than heterozygous (12.6 h) or wild‐type (13.6 h) patients. Total number of missense variants (median = 0, range 0–2) was associated with decreased PN sensitivity (β‐coefficient: −0.42, 95% confidence interval −0.72 to −0.12, P = .006). No association with treatment disruption was detected for the total number of missense variants or rs7349683.ConclusionIsolating toxicity sensitivity by accounting for exposure is a novel approach, and rs7349683 represents a promising marker for PN sensitivity that may be used to individualize paclitaxel treatment.