Role of Chemoradiotherapy in Elderly Patients With Limited-Stage Small-Cell Lung Cancer

Purpose To investigate outcomes for elderly patients treated with chemotherapy (CT) alone versus chemoradiotherapy (CRT) in the modern era by using a large national database. Patients and Methods Elderly patients (age ≥ 70 years) with limited-stage small-cell lung cancer clinical stage I to III who received CT or CRT were identified in the National Cancer Data Base between 2003 and 2011. Hierarchical mixed-effects logistic regression with clustering by reporting facility was performed to identify factors associated with treatment selection. Overall survival (OS) of patients receiving CT versus CRT was compared by using the log-rank test, Cox proportional hazards regression, and propensity score matching. Results A total of 8,637 patients were identified, among whom 3,775 (43.7%) received CT and 4,862 (56.3%) received CRT. The odds of receiving CRT decreased with increasing age, clinical stage III disease, female sex, and the presence of medical comorbidities (all P < .01). Use of CRT was associated with increased OS compared with CT on univariable and multivariable analysis (median OS, 15.6 v 9.3 months; 3-year OS, 22.0% v 6.3%; log-rank P < .001; Cox P < .001). Propensity score matching identified a matched cohort of 6,856 patients and confirmed a survival benefit associated with CRT (hazard ratio, 0.52; 95% CI, 0.50 to 0.55; P < .001). Subset analysis of CRT treatment sequence showed that patients alive 4 months after diagnosis derived a survival benefit with concurrent CRT over sequential CRT (median OS, 17.0 v 15.4 months; log-rank P = .01). Conclusion In elderly patients with limited-stage small-cell lung cancer, modern CRT appears to confer an additional OS advantage beyond that achieved with CT alone in a large population-based cohort. Our findings suggest that CRT should be the preferred strategy in elderly patients who are expected to tolerate the toxicities of the combined approach.