Carey, Lisa A

PURPOSE Breast-conserving therapy (BCT) is the preferred treatment for unifocal breast cancer (BC). The oncologic safety of BCT for multiple ipsilateral breast cancer (MIBC) has not been demonstrated in a prospective study. ACOSOG Z11102 (Alliance) is a phase II, single-arm, prospective trial designed to evaluate oncologic outcomes in patients undergoing BCT for MIBC. PATIENTS AND METHODS Women age 40 years and older with two to three foci of biopsy-proven cN0-1 BC were eligible. Patients underwent lumpectomies with negative margins followed by whole breast radiation with boost to all lumpectomy beds. The primary end point was cumulative incidence of local recurrence (LR) at 5 years with an a priori rate of clinical acceptability of <8%. RESULTS Among 270 women enrolled between November 2012 and August 2016, there were 204 eligible patients who underwent protocol-directed BCT. The median age was 61 years (range, 40-87 years). At a median follow-up of 66.4 months (range, 1.3-90.6 months), six patients developed LR for an estimated 5-year cumulative incidence of LR of 3.1% (95% CI, 1.3 to 6.4). Patient age, number of sites of preoperative biopsy–proven BC, estrogen receptor status and human epidermal growth factor receptor 2 status, and pathologic T and N categories were not associated with LR risk. Exploratory analysis showed that the 5-year LR rate in patients without preoperative magnetic resonance imaging (MRI; n = 15) was 22.6% compared with 1.7% in patients with a preoperative MRI (n = 189; P = .002). CONCLUSION The Z11102 clinical trial demonstrates that breast-conserving surgery with adjuvant radiation that includes lumpectomy site boosts yields an acceptably low 5-year LR rate for MIBC. This evidence supports BCT as a reasonable surgical option for women with two to three ipsilateral foci, particularly among patients with disease evaluated with preoperative breast MRI.

Abstract Purpose: We previously demonstrated that high levels of circulating methylated DNA are associated with subsequent disease progression in women with metastatic breast cancer (MBC). In this study, we evaluated the clinical utility of a novel liquid biopsy-breast cancer methylation (LBx-BCM) prototype assay using the GeneXpert cartridge system for early assessment of disease progression in MBC. Experimental Design: The 9-marker LBx-BCM prototype assay was evaluated in TBCRC 005, a prospective biomarker study, using plasma collected at baseline, week 4, and week 8 from 144 patients with MBC. Results: At week 4, patients with MBC with high cumulative methylation (CM) had a significantly shorter median PFS (2.88 months vs. 6.60 months, P = 0.001) and OS (14.52 months vs. 22.44 months, P = 0.005) compared with those with low CM. In a multivariable model, high versus low CM was also associated with shorter PFS (HR, 1.90; 95% CI, 1.20–3.01; P = 0.006). Change in CM from baseline to week 4 (OR, 4.60; 95% CI, 1.77–11.93; P = 0.002) and high levels of CM at week 4 (OR, 2.78; 95% CI, 1.29–5.99; P = 0.009) were associated with progressive disease at the time of first restaging. A robust risk model based on week 4 circulating CM levels was developed to predict disease progression as early as 3 months after initiating a new treatment. Conclusions: The automated LBx-BCM prototype assay is a promising clinical tool for detecting disease progression a month after initiating treatment in women with MBC undergoing routine care. The next step is to validate its clinical utility for specific treatments.

PURPOSE CALGB 40603 ( NCT00861705 ), a 2 × 2 randomized phase II trial, demonstrated that adding carboplatin or bevacizumab to weekly paclitaxel (wP) followed by doxorubicin and cyclophosphamide significantly increased the pathologic complete response (pCR) rate in stage II-III triple-negative breast cancer. We now report long-term outcomes (LTOs) and correlative science end points. PATIENTS AND METHODS The Kaplan-Meier method was used to estimate LTOs in 443 patients who initiated study treatment. Log-rank tests and Cox proportional hazards models evaluated the impact of clinical characteristics, pathologic response, calculated residual cancer burden (RCB) in patients with residual disease (RD), treatment assignment, and dose delivery during wP on LTOs, including event-free survival (EFS). Genomic predictors of treatment response and outcomes were assessed on pretreatment tumor samples by mRNA sequencing. RESULTS Among baseline characteristics, only the clinical stage was associated with LTOs. At a median follow-up of 7.9 years, LTOs were not significantly improved with either carboplatin or bevacizumab, overall or in patients with basal-like subtype cancers by genomic analysis. Patients with pCR (n = 205, 46.3%) had significantly higher 5-year EFS (85.5% v 56.6%, log-rank P < .0001) and overall survival (87.9% v 63.4%, P < .0001) rates compared with patients with RD, even those with RCB class I. Among clinical and genomic features, evidence of immune activation, including tumor-infiltrating lymphocytes and low B-cell receptor evenness, was associated with pCR and improved EFS. CONCLUSION Despite higher pCR rates, neither carboplatin nor bevacizumab appeared to improve LTOs although the study was not powered to assess these secondary end points. pCR was associated with superior LTOs even when compared with minimal RD. Markers of immune activation in pretreatment tumor biopsies were independently associated with higher pCR rates and improved survival.

Abstract Purpose: HER2 mutations (HER2mut) induce endocrine resistance in estrogen receptor–positive (ER+) breast cancer. Patients and Methods: In this single-arm multi-cohort phase II trial, we evaluated the efficacy of neratinib plus fulvestrant in patients with ER+/HER2mut, HER2 non-amplified metastatic breast cancer (MBC) in the fulvestrant-treated (n = 24) or fulvestrant-naïve cohort (n = 11). Patients with ER-negative (ER−)/HER2mut MBC received neratinib monotherapy in an exploratory ER− cohort (n = 5). Results: The clinical benefit rate [CBR (95% confidence interval)] was 38% (18%–62%), 30% (7%–65%), and 25% (1%–81%) in the fulvestrant-treated, fulvestrant-naïve, and ER− cohorts, respectively. Adding trastuzumab at progression in 5 patients resulted in three partial responses and one stable disease ≥24 weeks. CBR appeared positively associated with lobular histology and negatively associated with HER2 L755 alterations. Acquired HER2mut were detected in 5 of 23 patients at progression. Conclusions: Neratinib and fulvestrant are active for ER+/HER2mut MBC. Our data support further evaluation of dual HER2 blockade for the treatment of HER2mut MBC.

Recent epidemiologic data show an increasing incidence of breast cancer among premenopausal women in many higher-income countries. Among premenopausal women, those diagnosed under age 40 years experience inferior long-term outcomes, particularly in the setting of hormone receptor–positive, human epidermal growth factor receptor 2–negative disease. In addition to more advanced disease presentation and/or less favorable disease biology, suboptimal adjuvant endocrine therapy (ET) has emerged as an important driver of this age-related disparity. Historically, young women have been excluded from treatment with aromatase inhibitors (AIs), attained low rates of chemotherapy-related amenorrhea, and exhibited low adherence to ET. Recently, several studies have demonstrated treatment with ovarian function suppression (OFS) during the first 5 years postdiagnosis to be associated with improvements in breast cancer recurrence and mortality, with additional benefits achieved from pairing OFS with an AI. As the first 5 years of ET for premenopausal women has been transformed, extended ET, administered in years 5-10 postdiagnosis, has also become more common. However, the only studies of extending ET in premenopausal women have tested an additional 5 years of tamoxifen following an initial 5 years of tamoxifen and studies of AIs in the second 5 years have been limited to postmenopausal women. Herein, we review available data concerning potential benefits and risks to be considered when counseling premenopausal women on extended ET, including the continuation of OFS. We offer a pragmatic framework to support decision making given the current body of knowledge and call out the need for additional research into this issue.

PURPOSE This guideline updates recommendations of the ASCO guideline on chemotherapy and targeted therapy for patients with human epidermal growth factor receptor 2–negative metastatic breast cancer (MBC) that is either endocrine-pretreated or hormone receptor (HR)–negative. METHODS An Expert Panel conducted a targeted systematic literature review guided by a signals approach to identify new, potentially practice-changing data that might translate into revised guideline recommendations. RESULTS The Expert Panel reviewed abstracts from the literature review and retained 14 articles. RECOMMENDATIONS Patients with triple-negative, programmed cell death ligand-1–positive MBC may be offered the addition of immune checkpoint inhibitor to chemotherapy as first-line therapy. Patients with triple-negative, programmed cell death ligand-1–negative MBC should be offered single-agent chemotherapy rather than combination chemotherapy as first-line treatment, although combination regimens may be offered for life-threatening disease. Patients with triple-negative MBC who have received at least two prior therapies for MBC should be offered treatment with sacituzumab govitecan. Patients with triple-negative MBC with germline BRCA mutations previously treated with chemotherapy may be offered a poly (ADP-ribose) polymerase inhibitor rather than chemotherapy. Patients with HR-positive human epidermal growth factor receptor 2–negative MBC for whom chemotherapy is being considered should be offered single–agent chemotherapy rather than combination chemotherapy, although combination regimens may be offered for highly symptomatic or life-threatening disease. Patients with HR-positive MBC with disease progression on an endocrine agent may be offered treatment with either endocrine therapy with or without targeted therapy or single-agent chemotherapy. Patients with HR-positive MBC with germline BRCA mutations no longer benefiting from endocrine therapy may be offered a poly (ADP-ribose) polymerase inhibitor rather than chemotherapy. No recommendation regarding when a patient's care should be transitioned to hospice or best supportive care alone is possible. Additional information is available at www.asco.org/breast-cancer-guidelines .

PURPOSE Predictive biomarkers to identify patients with human epidermal growth factor receptor 2 (HER2)–positive breast cancer who may benefit from targeted therapy alone are required. We hypothesized that early measurements of tumor maximum standardized uptake value corrected for lean body mass (SULmax) on 18 F-labeled fluorodeoxyglucose positron emission tomography-computed tomography (PET-CT) would predict pathologic complete response (pCR) to pertuzumab and trastuzumab (PT). PATIENTS AND METHODS Patients with stage II or III, estrogen receptor–negative, HER2-positive breast cancer received four cycles of neoadjuvant PT. 18 F-labeled fluorodeoxyglucose positron emission tomography-computed tomography was performed at baseline and 15 days after PT initiation (C1D15). Eighty evaluable patients were required to test the null hypothesis that the area under the curve of percent change in SULmax by C1D15 predicting pCR is ≤ 0.65, with a one-sided type I error rate of 10%. RESULTS Eighty-eight women were enrolled (83 evaluable), and 85% (75 of 88) completed all four cycles of PT. pCR after PT alone was 22%. Receiver operator characteristic analysis of percent change in SULmax by C1D15 yielded an area under the curve of 0.72 (80% CI, 0.64 to 0.80; one-sided P = .12), which did not reject the null hypothesis. However, between patients who obtained pCR and who did not, a significant difference in median percent reduction in SULmax by C1D15 was observed (63.8% v 41.8%; P = .004) and SULmax reduction ≥ 40% was more prevalent (83% v 52%; P = .03; positive predictive value, 31%). Participants not obtaining a 40% reduction in SULmax by C1D15 were unlikely to obtain pCR (negative predictive value, 91%). CONCLUSION Although the primary objective was not met, early changes in SULmax predict response to PT in estrogen receptor–negative and HER2-positive breast cancer. Once optimized, this quantitative imaging strategy may facilitate tailoring of therapy in this setting.

Abstract Purpose: We evaluated the prognostic and predictive value of circulating tumor cells (CTCs) hormone receptor–positive (HR+) metastatic breast cancer (MBC) patients randomized to letrozole alone or letrozole plus bevacizumab in the first-line setting (CALGB 40503). Experimental Design: Blood samples were collected at pretreatment and three additional time points during therapy. The presence of ≥5 CTCs per 7.5 mL of blood was considered CTC positive. Association of CTCs with progression-free survival (PFS) and overall survival (OS) was assessed using Cox regression models. Results: Of 343 patients treated, 294 had CTC data and were included in this analysis. Median follow-up was 39 months. In multivariable analysis, CTC-positive patients at baseline (31%) had significantly reduced PFS [HR, 1.49; 95% confidence interval (CI), 1.12–1.97] and OS (HR, 2.08; 95% CI, 1.49–2.93) compared with CTC negative. Failure to clear CTCs during treatment was associated with significantly increased risk of progression (HR, 2.2; 95% CI, 1.58–3.07) and death (HR, 3.4; 95% CI, 2.36–4.88). CTC-positive patients who received only letrozole had the worse PFS (HR, 2.3; 95% CI, 1.54–3.47) and OS (HR, 2.6; 95% CI, 1.59–4.40). Median PFS in CTC-positive patients was significantly longer (18.0 vs. 7.0 months) in letrozole plus bevacizumab versus letrozole arm (P = 0.0009). Restricted mean survival time analysis further revealed that addition of bevacizumab was associated with PFS benefit in both CTC-positive and CTC-negative patients, but OS benefit was only observed in CTC-positive patients. Conclusions: CTCs were highly prognostic for the addition of bevacizumab to first-line letrozole in patients with HR+ MBC in CALGB 40503. Further research to determine the potential predictive value of CTCs in this setting is warranted.