Wolff, Antonio C

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: Preclinical data demonstrating androgen receptor (AR)–positive (AR+) triple-negative breast cancer (TNBC) cells are sensitive to AR antagonists, and PI3K inhibition catalyzed an investigator-initiated, multi-institutional phase Ib/II study TBCRC032. The trial investigated the safety and efficacy of the AR-antagonist enzalutamide alone or in combination with the PI3K inhibitor taselisib in patients with metastatic AR+ (≥10%) breast cancer. Patients and Methods: Phase Ib patients [estrogen receptor positive (ER+) or TNBC] with AR+ breast cancer received 160 mg enzalutamide in combination with taselisib to determine dose-limiting toxicities and the maximum tolerated dose (MTD). Phase II TNBC patients were randomized to receive either enzalutamide alone or in combination with 4 mg taselisib until disease progression. Primary endpoint was clinical benefit rate (CBR) at 16 weeks. Results: The combination was tolerated, and the MTD was not reached. The adverse events were hyperglycemia and skin rash. Overall, CBR for evaluable patients receiving the combination was 35.7%, and median progression-free survival (PFS) was 3.4 months. Luminal AR (LAR) TNBC subtype patients trended toward better response compared with non-LAR (75.0% vs. 12.5%, P = 0.06), and increased PFS (4.6 vs. 2.0 months, P = 0.082). Genomic analyses revealed subtype-specific treatment response, and novel FGFR2 fusions and AR splice variants. Conclusions: The combination of enzalutamide and taselisib increased CBR in TNBC patients with AR+ tumors. Correlative analyses suggest AR protein expression alone is insufficient for identifying patients with AR-dependent tumors and knowledge of tumor LAR subtype and AR splice variants may identify patients more or less likely to benefit from AR antagonists.

Members of the Translational Breast Cancer Research Consortium conducted an expert‐driven literature review to identify a list of domains and to evaluate potential measures of these domains for inclusion in a list of preferred measures. Measures were included if they were easily available, free of charge, and had acceptable psychometrics based on published peer‐reviewed analyses. A total of 22 domains and 52 measures were identified during the selection process. Taken together, these measures form a reliable and validated list of measurement tools that are easily available and used in multiple cancer trials to assess patient‐reported outcomes in relevant patients.

Abstract Purpose: Prior neoadjuvant trials with 12 weeks of dual anti-HER2 therapy without chemotherapy demonstrated a meaningful pathologic complete response (pCR) in patients with HER2-positive breast cancer. In this trial, we sought to determine whether longer treatment would increase the rate of pCR. Patients and Methods: TBCRC023 (NCT00999804) is a randomized phase II trial combining a Simon phase II design in the experimental arm with a pick-the-winner design, not powered for direct comparison. Women with HER2-positive breast tumors measuring ≥2 cm (median = 5 cm) were randomized in a 1:2 ratio to 12 versus 24 weeks of lapatinib and trastuzumab. Letrozole (along with ovarian suppression if premenopausal) was administered in patients whose tumors were also estrogen receptor (ER) positive. All evaluable patients were assessed for in-breast pCR. Results: Ninety-seven patients were enrolled (33 in 12-week arm and 64 in 24-week arm), of whom 94 were evaluable. Median age was 51 years, and 55% were postmenopausal. Median tumor size was 5 cm, and 65% were ER-positive. The rate of pCR in the 24-week arm was 28% and numerically superior to the 12-week arm (12%). This was driven by increased pCR in the ER-positive subgroup (33% vs. 9%). Study treatment was well tolerated, with grade 1–2 diarrhea and acneiform rash being the most common toxicities. Conclusions: Treatment with dual anti-HER2 therapy for 24 weeks led to a numeric increase in pCR rate in women with HER2-positive breast cancer, without using chemotherapy. If validated, this approach may help identify patients who may benefit from deescalation of therapy.

Purpose CALGB 49907 showed the superiority of standard therapy, which included either cyclophosphamide/doxorubicin (AC) or cyclophosphamide/methotrexate/fluorouracil over single-agent capecitabine in the treatment of patients age ≥ 65 with early-stage breast cancer. The treatment allowed dosing adjustments of methotrexate and capecitabine for pretreatment renal function. The purpose of the current analysis was to assess the relationship between pretreatment renal function and five end points: toxicity, dose modification, therapy completion, relapse-free survival, and overall survival. Methods Pretreatment renal function was defined as creatinine clearance (CrCl) using the Cockcroft-Gault equation. Multivariable logistic and proportional hazards regression were used to model separately for each regimen the relationship between CrCl and the first three binary end points and the last two time-to-event end points, respectively, after adjusting for variables of prognostic importance. Results Six hundred nineteen assessable patients were analyzed. The incidence of stage III (moderate) or stage IV (severe) renal dysfunction was 72%, 64%, and 75% for treatment with cyclophosphamide/methotrexate/fluorouracil, AC, and capecitabine, respectively. There was no relationship for any regimen between pretreatment renal function and the five end points. For AC, as CrCl increased, the odds of nonhematologic toxicity decreased (P = .008), whereas for capecitabine, as CrCl increased, the odds of experiencing toxicity of any type also increased (P = .035). Patients with renal insufficiency who received dose modifications were not at increased risk for complications compared with those who did not have renal insufficiency and received a full dose. Conclusion Excluding from clinical trials patients with renal insufficiency but good performance status on the basis of concern of excessive hematologic toxicity or poor outcomes may not be justified with appropriate dosing modifications. Results should be considered in the design of clinical trials for older patients.

Background Lapatinib (L) plus trastuzumab (T) improves outcomes for metastatic human epidermal growth factor 2–positive breast cancer and increases the pathologic complete response in the neoadjuvant setting, but their role as adjuvant therapy remains uncertain. Methods In the Adjuvant Lapatinib and/or Trastuzumab Treatment Optimization trial, patients with centrally confirmed human epidermal growth factor 2–positive early breast cancer were randomly assigned to 1 year of adjuvant therapy with T, L, their sequence (T→L), or their combination (L+T). The primary end point was disease-free survival (DFS), with 850 events required for 80% power to detect a hazard ratio (HR) of 0.8 for L+T versus T. Results Between June 2007 and July 2011, 8,381 patients were enrolled. In 2011, due to futility to demonstrate noninferiority of L versus T, the L arm was closed, and patients free of disease were offered adjuvant T. A protocol modification required P ≤ .025 for the two remaining pairwise comparisons. At a protocol-specified analysis with a median follow-up of 4.5 years, a 16% reduction in the DFS hazard rate was observed with L+T compared with T (555 DFS events; HR, 0.84; 97.5% CI, 0.70 to 1.02; P = .048), and a 4% reduction was observed with T→L compared with T (HR, 0.96; 97.5% CI, 0.80 to 1.15; P = .61). L-treated patients experienced more diarrhea, cutaneous rash, and hepatic toxicity compared with T-treated patients. The incidence of cardiac toxicity was low in all treatment arms. Conclusion Adjuvant treatment that includes L did not significantly improve DFS compared with T alone and added toxicity. One year of adjuvant T remains standard of care.

Purpose To determine long-term outcomes in a clinical trial evaluating the role of taxane type and schedule in operable breast cancer and evaluate the impact of obesity and black race on outcome. Patients and Methods A total of 4,954 eligible women with stage II to III breast cancer treated with four cycles of doxorubicin plus cyclophosphamide were randomly assigned to receive paclitaxel or docetaxel every 3 weeks for four doses or weekly for 12 doses using a 2 × 2 factorial design. The primary end point was disease-free survival (DFS). Results are expressed as hazard ratios (HRs) from Cox proportional hazards models. All P values are two sided. Results When compared with the standard every-3-week paclitaxel arm, after a median follow-up of 12.1 years, DFS significantly improved and overall survival (OS) marginally improved only for the weekly paclitaxel (HR, 0.84; P = .011 and HR, 0.87; P = .09, respectively) and every-3-week docetaxel arms (HR, 0.79; P = .001 and HR, 0.86; P = .054, respectively). Weekly paclitaxel improved DFS and OS (HR, 0.69; P = .010 and HR, 0.69; P = .019, respectively) in triple-negative breast cancer. For hormone receptor–positive, human epidermal growth factor receptor 2–nonoverexpressing disease, no experimental arm improved OS, and black race and obesity were associated with increased risk of breast cancer recurrence and death. Conclusion Improved outcomes initially observed for weekly paclitaxel were qualitatively similar but quantitatively less pronounced with longer follow-up, although exploratory analysis suggested substantial benefit in triple-negative disease. Further research is required to understand why obesity and race influence clinical outcome in hormone receptor–positive disease.

AbstractBackgroundStudies point to a direct association between social support and better cancer outcomes. This study examined whether baseline social support is associated with better survival and fewer chemotherapy‐related adverse events in older, early‐stage breast cancer patients.MethodsThis study is a pre‐planned secondary analysis of CALGB 49907/Alliance A171301, a randomized trial that compared standard adjuvant chemotherapy versus capecitabine in breast cancer patients 65 years of age or older. A subset reported on the extent of their social support with questionnaires that were completed 6 times over 2 years.ResultsThe median age of this 331‐patient cohort was 72 years (range: 65, 90); 179 (55%) were married, and 210 (65%) lived with someone. One hundred forty‐five patients (46%) described a social network of 0–10 people; 110 (35%) of 11–25; and 58 (19%) of 26 or more. The Medical Outcomes Study (MOS) social support survey revealed that the median scores (range) for emotional/informational, tangible, positive social interaction, and affectionate social support were 94 (3, 100), 94 (0, 100), 96 (0, 100), and 100 (8, 100), respectively. Social support scores appeared stable over 2 years and higher (more support) than in other cancer settings. No statistically significant associations were observed between social support and survival and adverse events in multivariate analyses. However, married patients had smaller tumors, and those with arthritis reported less social support.ConclusionAlthough social support did not predict survival and adverse events, the exploratory but plausible inverse associations with larger tumors and arthritis suggest that social support merits further study. Copyright © 2015 John Wiley & Sons, Ltd.

Abstract Purpose: Tigatuzumab (TIG), an agonistic anti-DR5 antibody, triggers apoptosis in DR5+ human tumor cells without crosslinking. TIG has strong in vitro/in vivo activity against basal-like breast cancer cells enhanced by chemotherapy agents. This study evaluates activity of TIG and chemotherapy in patients with metastatic triple-negative breast cancer (TNBC). Experimental Design: Randomized 2:1 phase II trial of albumin-bound paclitaxel (nab-PAC) ± TIG in patients with TNBC stratified by prior chemotherapy. Patients received nab-PAC weekly × 3 ± TIG every other week, every 28 days. Primary objective was within-arm objective response rate (ORR). Secondary objectives were safety, progression-free survival (PFS), clinical benefit, and TIG immunogenicity. Metastatic research biopsies were required. Results: Among 64 patients (60 treated; TIG/nab-PAC n = 39 and nab-PAC n = 21), there were 3 complete remissions (CR), 8 partial remissions (PR; 1 almost CR), 11 stable diseases (SD), and 17 progressive diseases (PD) in the TIG/nab-PAC arm (ORR, 28%), and no CRs, 8 PRs, 4 SDs, and 9 PDs in the nab-PAC arm (ORR, 38%). There was a numerical increase in CRs and several patients had prolonged PFS (1,025+, 781, 672, 460, 334) in the TIG/nab-PAC arm. Grade 3 toxicities were 28% and 29%, respectively, with no grade 4–5. Exploratory analysis suggests an association of ROCK1 gene pathway activation with efficacy in the TIG/nab-PAC arm. Conclusions: ORR and PFS were similar in both. Preclinical activity of TIG in basal-like breast cancer and prolonged PFS in few patients in the combination arm support further investigation of anti-DR5 agents. ROCK pathway activation merits further evaluation. Clin Cancer Res; 21(12); 2722–9. ©2015 AACR. See related article by Paoletti et al., p. 2771