Adjuvant therapy in stage IIIA-N2 non-small cell lung cancer after neoadjuvant concurrent chemoradiotherapy followed by surgery

Background: This study aimed to determine whether adjuvant therapy improves survival in patients with stage IIIA-N2 non-small cell lung cancer (NSCLC) after neoadjuvant concurrent chemoradiotherapy (CCRT) followed by surgery. Methods: We retrospectively reviewed 467 consecutive patients with stage IIIA-N2 NSCLC who received neoadjuvant CCRT followed by surgery between 2004 and 2013. From these, we identified 398 eligible patients and their clinical outcomes were compared according to whether adjuvant therapy was provided. Results: In total, 296 patients (74%) received adjuvant therapy consisting of chemotherapy alone (n=71) radiotherapy alone (n=118) and both chemotherapy and radiotherapy (n=107). Adjuvant therapy was not given to remaining 102 patients. Patients who receiving adjuvant therapy were significantly younger (P=0.001), and predominantly male (P=0.014) compared to patients who did not receive adjuvant therapy. Regarding to the pathologic response, the adjuvant therapy group had a significantly poor pathologic response. However, the 5-year overall survival (OS) rate did not significantly differ between the groups (adjuvant therapy group, 52.9%; no adjuvant therapy group, 54.9%; P=0.369). After adjusting for age, sex, type of operation, cell type and yp stage, adjuvant therapy was significantly associated with better OS (hazard ratio =0.59; 95% CI, 0.38-0.92; P=0.019) and disease free survival (hazard ratio =0.62; 95% CI, 0.44-0.87; P=0.006). Conclusions: Our data indicate that adjuvant therapy is more often given to patients with poor pathologic findings. Adjuvant treatment after trimodal therapy is a significant predictor of survival after adjustment of clinical variables.