Adjuvant chemotherapy for elderly patients with non-small-cell lung cancer

Background Adjuvant chemotherapy after complete surgical resection is currently the standard of care for patients with stage IB, II, or IIIA non-small-cell lung cancer. However, the generalizability of this treatment to elderly patients is controversial. We investigated the effects of adjuvant chemotherapy in patients aged over 75 years with stage IB-IIIA non-small-cell lung cancer. Methods We retrospectively analyzed 246 consecutive patients aged over 75 years with stage IB-IIIA non-small-cell lung cancer who underwent standard lung cancer surgery between January 2001 and December 2015. They were divided into 102 who had adjuvant chemotherapy and 144 who had none (control group). The outcomes were compared between the two groups, and prognostic factors were evaluated. Results Relapse-free survival and overall survival were significantly shorter in the control group than the chemotherapy group ( p = 0.006 and p = 0.008, respectively). In multivariable analyses, adjuvant chemotherapy was found to be an independent prognostic factor for relapse-free survival and overall survival (hazard ratio = 0.594, 95% confidence interval: 0.396-0.893, p = 0.012; and hazard ratio = 0.616, 95% confidence interval: 0.397-0.957, p = 0.031, respectively). After inverse-probability-of-treatment weighting adjustment using the propensity score for baseline characteristics, chemotherapy almost improved relapse-free survival and overall survival (hazard ratio = 0.652, 95% confidence interval: 0.433-0.981, p = 0.040; and hazard ratio = 0.657, 95% confidence interval: 0.429-1.004, p = 0.052, respectively). Conclusions Adjuvant chemotherapy improved the prognosis after standard lung cancer surgery in patients aged over 75 years with stage IB-IIIA non-small-cell lung cancer.