Improved uptake and survival with systemic treatments for metastatic non-small cell lung cancer: younger versus older adults

Background: Over the past decade, there has been increasing availability of novel therapeutics with improved tolerability and efficacy for advanced non-small cell lung cancer (NSCLC). The study goals were: to compare the uptake of systemic therapy (ST) before and after the availability of targeted tyrosine kinase inhibitors (TKI) and immunotherapy and to examine the changes in overall survival (OS) over time between younger and older adults with advanced NSCLC.

Methods: All patients with advanced NSCLC referred to British Columbia (BC) Cancer in 2009, 2011, 2015 and 2017 were included. One-year time points were based on molecular testing implementation and funded drug availability: baseline (2009), epidermal growth factor receptor TKI (2011), anaplastic lymphoma kinase TKI (2015) and Programed Death-1 (PD-1) inhibitors (2017). Age groups were <70years and ≥70years. Baseline demographics, simplified comorbidity scores (SCS), disease characteristics, and ST details were collected retrospectively. Variables were compared using X2, Fisher's exact tests and logistic-regression analysis. OS was calculated using the Kaplan-Meier method and compared using the log-rank test.

Results: 3325 patients were identified. Baseline characteristics were compared between ages < 70 years and ≥ 70 years for each time cohort with significant differences noted in baseline Eastern Cooperative Oncology Group (ECOG) performance status and SCS. The rate of ST delivery trended upwards over time with age <70 years: 2009 44%, 2011 53%, 2015 50% and 2017 52% and age ≥70 years: 22%, 25%, 28% and 29% respectively. Predictors for decreased use of ST for age <70 years: ECOG ≥2, SCS ≥9, year 2011, and smoking history; and age ≥70 years: ECOG ≥2, years 2011 and 2015, and smoking history. The median OS of patients who received ST improved from 2009 to 2017: age <70 years 9.1 m vs. 15.5 m and age ≥70 years 11.4 m vs. 15.0 m.

Conclusions: There was an increased uptake of ST for both age groups with the introduction of novel therapeutics. Although a smaller proportion of older adults received ST, those who received treatment had comparable OS to their young counterpart. The benefit of ST in both age groups was seen across the different types of treatments. With careful assessment and selection of appropriate candidates, older adults with advanced NSCLC appear to benefit from ST.