Time-to-Treatment-Failure and Related Outcomes Among 1000+ Advanced Non–Small Cell Lung Cancer Patients: Comparisons Between Older Versus Younger Patients (Alliance A151711)

Abstract Background Time-to-treatment-failure (TTF) is the interval from chemotherapy initiation to premature discontinuation. We evaluated TTF based on age. Methods Pooled analyses were conducted with, first-line chemotherapy trials for advanced non-small cell lung cancer (CALGB 9730, 30203, and 30801). Comparisons -- with age 65+ and 70+ years -- were performed for TTF (primary endpoint), reasons for early chemotherapy cessation, grade 3+ adverse events, and overall survival. Results Among 1006 patients, 460 (46%) were 65+ years of age. 145 older patients (32% of this age cohort) completed all six, planned chemotherapy cycles, as did 170 (32%) younger patients. Median TTF was 2.9 months (95% confidence interval (CI) = (2.7, 3.2)) in older and 3 months (95% CI=(2.9, 3.5)) in younger patients; adjustment for performance status and stratification by chemotherapy by trial yielded no statistically significant age-based difference in TTF. However, reasons for early chemotherapy cessation differed between age groups (multivariate p=0.004). Older patients were less likely to discontinue from cancer progression (41% versus 55%) and more likely from toxicity or patient choice (16% and 15%, respectively) compared to younger patients (13% and 6%, respectively). Older patients were more likely to experience grade 3+ adverse events (86% versus 79%) with no statistically significant difference in survival. An age cut point of 70+ showed no difference in TTF, a lower trend of early cessation due to cancer progression, and somewhat shorter older patient survival. Conclusion TTF was comparable between older and younger patients; but different, age-based, and potentially modifiable reasons account for it.