Patterns of treatment and survival among older patients with stage III non-small cell lung cancer

Introduction: Patterns of treatment and survival are largely unknown for older patients with stage III non-small cell lung cancer (NSCLC) in daily clinical practice. Methods: All patients >= 65 years with stage III NSCLC (2009-2013) were included from the population-based Netherlands Cancer Registry. Descriptive and multivariable treatment and survival analyses were stratified for patients aged 65-74 years and >= 75 years. Results: Compared to older patients (n = 3163), those aged 65-74 years (n = 3876) underwent more often surgery (21% vs 12% for stage IIIA), chemoradiotherapy (47% vs 22% for both stage IIIA and IIIB), and chemotherapy (23% vs 12% for stage IIIB), and received less radiotherapy (8% vs 22% for both stage IIIA and IIIB). One-year survival was significantly higher among patients aged 65-74 compared to those aged >= 75 (61% vs 43%, for stage IIIA and 45% vs 30% for stage IIIB; P <.01). However, stratification of treatment showed similar survival rates between age groups. Among patients aged 65-74 years, the multivariably adjusted hazard ratio (HR) of death was twice as high for patients receiving radiotherapy (HR 1.9 (95%CI 1.6-2.2) for stage IIIA and HR 2.5 (95%CI 2.1-3.0) for stage IIIB) and chemotherapy (HR 2.2 (95%CI 1.9-2.5) and HR 2.2 (95%CI 1.8-2.7), respectively) compared to chemoradiotherapy, and were slightly lower for patients aged >= 75 years receiving radiotherapy (HR 1.6 (95%CI 1.4-1.9) and HR 1.8 (95%CI 1.5-2.1), respectively) and chemotherapy (HR 2.2 (95%CI 1.8-2.7) and HR 1.8 (95%CI 1.5-2.2), respectively). Comorbidity was not significantly associated with poorer survival (p = .07). Conclusion: Chemoradiotherapy was more often applied among patients aged 65-74 years compared to those aged >= 75. While survival was worse for patients aged >= 75 years, differences between age groups largely disappeared after stratification for treatment. Future research should focus on predictive patient characteristics to distinguish patients within the heterogeneous older population who can benefit from curative-intent treatment.