Muss, Hyman B.

PURPOSE Older women with breast cancer remain under-represented in clinical trials. The Cancer and Leukemia Group B 49907 trial focused on women age 65 years and older. We previously reported the primary analysis after a median follow-up of 2.4 years. Standard adjuvant chemotherapy showed significant improvements in recurrence-free survival (RFS) and overall survival compared with capecitabine. We now update results at a median follow-up of 11.4 years. PATIENTS AND METHODS Patients age 65 years or older with early breast cancer were randomly assigned to either standard adjuvant chemotherapy (physician’s choice of either cyclophosphamide, methotrexate, and fluorouracil or cyclophosphamide and doxorubicin) or capecitabine. An adaptive Bayesian design was used to determine sample size and test noninferiority of capecitabine. The primary end point was RFS. RESULTS The design stopped accrual with 633 patients at its first sample size assessment. RFS remains significantly longer for patients treated with standard chemotherapy. At 10 years, in patients treated with standard chemotherapy versus capecitabine, the RFS rates were 56% and 50%, respectively (hazard ratio [HR], 0.80; P = .03); breast cancer–specific survival rates were 88% and 82%, respectively (HR, 0.62; P = .03); and overall survival rates were 62% and 56%, respectively (HR, 0.84; P = .16). With longer follow-up, standard chemotherapy remains superior to capecitabine among hormone receptor–negative patients (HR, 0.66; P = .02), but not among hormone receptor–positive patients (HR, 0.89; P = .43). Overall, 43.9% of patients have died (13.1% from breast cancer, 16.4% from causes other than breast cancer, and 14.1% from unknown causes). Second nonbreast cancers occurred in 14.1% of patients. CONCLUSION With longer follow-up, RFS remains superior for standard adjuvant chemotherapy versus capecitabine, especially in patients with hormone receptor–negative disease. Competing risks in this older population dilute overall survival benefits.

e18132 Background: Older adults (65+ years) make up > 50% of cancer patients in the US,1 yet, older patient enrollment onto trials remains < 30%.2 This study’s aim was to determine the association between trial level variables and accrual rates of adults 65+ to better design trials that can more improve enrollment of these patients. Methods: We analyzed enrollment percentages of patients age 65+ in non-age specific Alliance trials with > 50 patients, that completed accrual between 1995- 2015. Enrollment percentage by 65+ for each study was compared to cancer incidence percentage by 65+ according to the Surveillance, Epidemiology, and End Results (SEER) Program for the same time periods. Enrollment Disparity Difference (EDD)3, defined as the difference between SEER incidence percentage of patients 65+ and the trial percentage enrollment of 65+ was calculated for each trial ( SEER % – trial %). Univariate analyses (UVA) were performed using simple linear regression to determine trial variables associated with larger EDDs (higher disparity). Variables that had an F-test p-value < 0.20 were included in a multivariable fixed-effects linear model for multivariate analysis (MVA). Results: Median age of 66,708 patients across 237 trials with 10 cancer types was 60 years. Average % of 65+ in trials was lower than average SEER comparison % 65+ per trial (37.6% vs. 57.8%). The median trial EDD, was 16.7%. On UVA, cancer type was significantly associated with higher EDD (see Table). Use of fewer modalities (1, 2, vs 3+) was associated with lower estimated EDDs (1 = -11 [+/-3.6], 2 = -8.9 [+/-3.9], F-test p = .012). On MVA, non-genitourinary (GU) cancer type, number of treatment modalities, and the phase (II or III compared to observational/other) were all significantly associated with higher EDD. Conclusions: Older adults were under-represented in this large sample of trials. This information can be used as a platform to better design disease-specific trials to improve older patient accrual, particularly in disease areas which are under-performing. Support: U10CA180821, U10CA180882, UG1CA189823: https://acknowledgments.alliancefound.org . References: 1. Smith BD et al. J Clin Oncol 27:2758-65, 2009; 2. Hurria A, et al. J Geriatr Oncol 1:40-44, 2010; 3. Pang HH, et al. J Clin Oncol, 2016.[Table: see text]

Abstract Background Less than 3% of older patients with cancer are enrolled in clinical trials. To reverse this underrepresentation, we compared older patients enrolled with older-patient-specific trials, defined as those designed for older patients with cancer, with those enrolled in age-unspecified trials. Materials and Methods We focused on individual patient data from those ≥65 years (younger patients excluded) and included all Alliance phase III adjuvant breast cancer trials from 1985–2012. Results Among 2,277 patients, 1,014 had been enrolled to older-patient-specific and 1,263 to age-unspecified trials. The median age (range) in the older-patient-specific trials was 72 (65–89) years compared with 68 (65–84) years in the cohort of older patients in age-unspecified trials; p &lt; .0001. A greater percentage of patients 75 years or older had enrolled in older-patient-specific trials compared with the cohort of age-unspecified trials: 26% versus 6% (p &lt; .0001). Median overall survival (OS) was 12.8 years (95% confidence interval [CI], 11.9–13.7) and 13.5 years (95% CI, 12.9–14.1) for older-patient-specific and age-unspecified trials, respectively. OS was comparable (hazard ratio [HR], 1.08; 95% CI, 0.92–1.28; p = .34; referent: age-unspecified trials), after adjusting for age, estrogen receptor status, tumor size, and lymph node status. Similar findings were reached for recurrence-free survival. A lower rate of grade 3–5 adverse events (hematologic and nonhematologic) was reported in older-patient-specific trials (43% vs. 58%; p &lt; .0001). Sensitivity analysis with chemotherapy only trials and subset analysis, adjusted for performance score, yielded similar OS results. Conclusion Older-patient-specific trials appear to address this underrepresentation of older patients with ostensibly comparable outcomes. Clinical trial identification numbers. NCT00003088 (CALGB 9741); NCT00024102 (CALGB 49907); NCT00068601 (CALGB 40401); NCT00005970 (NCCTG N9831)

Abstract Purpose A few previous studies report a direct relationship between older age and chemotherapy-induced neuropathy. This study further evaluated this adverse event's age-based risk. Methods CALGB 40101 investigated adjuvant paclitaxel (80 mg/m2 once per week or 175 mg/m2 every 2 weeks) in patients with breast cancer and served as a platform for the current study that investigated age-based differences in neuropathy. Grade 2 or worse neuropathy, as per Common Terminology Criteria for Adverse Events version 4, was the primary endpoint; patients were assessed at baseline, every 6 months for 2 years, and then annually for 15 years. Results Among these 1,881 patients, 230 were 65 years of age or older, 556 were 55–64 years, and 1,095 were younger than 55; 1,226 neuropathy events (commonly grade 1 or 2) were reported in 65% of the cohort. The number of grade 2 or worse events was 63 (27%), 155 (28%), and 266 (24%) within respective age groups (p = .14). In univariate analysis, only motor neuropathy had a higher age-based incidence: 19 (8%), 43 (8%), and 60 (5%), respectively (p = .04); in multivariate analyses, this association was no longer statistically significant. Other endpoints, such as time to onset of neuropathy (time from trial enrollment to neuropathy development) and time to improvement (time from maximal grade sensory neuropathy to a one-category improvement), showed no statistically significant age-based differences. In contrast, obesity was associated with neuropathy, and every 2-week paclitaxel was associated with trends toward neuropathy. Conclusion Although paclitaxel-induced neuropathy is common, older age is not an independent risk factor. Clinical trial identification number. NCT00041119 (CALGB 40101).

e21545 Background: A nocebo is an inert substance that causes adverse events. Although previous studies have examined the favorably positive (placebo) effects of an inert substance, few studies have examined negative (nocebo) effects, particularly in older patients who sometimes experience frequent and severe adverse events from cancer therapy. Methods: This study focused on placebo/nocebo-exposed patients who participated in two double-blind, placebo-controlled, cancer therapeutic studies, namely, North Central Cancer Treatment Group (NCCTG) 97-24-51 and American College of Surgeons Oncology Group (ACOSOG) Z9001, with the goal of reporting comparative, age-based adverse event rates. Results: Among the 446 patients who received placebo/nocebo exclusively, 161 were 65 years of age or older at the time of respective trial entry; 5234 adverse events occurred. Unadjusted adverse event rates did not differ significantly between patients 65 years of age or older and those younger: rate ratio (99% confidence intervals (CI): 1.01 (0.47, 2.02) with similar findings for grade 2 or worse adverse events and for all symptom-driven adverse events (for example, pain, loss of appetite, anxiety). Adjustment for sex, ethnicity, baseline performance score, and trial resulted in no significant age-based rate differences in adverse event rates. Similar findings were observed with an age threshold of 70. Conclusions: A nocebo effect appears to occur irrespective of age. This observation suggests that adverse events should be taken no less seriously in older than in younger cancer patients and that education to manage patients’ expectations from cancer therapy might improve tolerability. [Table: see text]