Lichtman, Stuart M.

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 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).

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.