Postoperative Chemotherapy after Pneumonectomy in PIIB-PIIIB Non-Small-Cell Lung Cancer: A Safe Treatment but Lack of Survival Benefits

Abstract Background. Few reports have focused on postoperative chemotherapy (POCT) in stage pIIB-pIIIB non-small-cell lung cancer (NSCLC) patients after pneumonectomy. The safety and survival benefits of POCT have not been thoroughly evaluated among these patients. Methods. Records of patients who underwent pneumonectomy for stage pIIB-pIIIB NSCLC at a single institution between Jan. 2008 and Dec. 2016 were retrospectively reviewed.Results. Among the 169 patients included, 143 cases received R0 resection and survived over 90 days postoperatively. Among these, 98 cases received POCT (Chem(+) cohort), and 45 cases did not (Chem(-) cohort). The 5-year rate of non-cancer specific death (death caused by reasons other than cancer) after pneumonectomy was 7% in all patients, 11.1% in the Chem(-) cohort and 5.5% in the Chem(+) cohort. The recurrence rate had a tendency to decrease after POCT (HR=0.95, P=0.883), both in the local recurrence and distant recurrence (HR=0.58, P=0.290; HR=0.85, P=0.645), but the change did not reach statistical significance. pTNM stage and pleural invasion were independent factors associated with the recurrence rate (HR=1.91, P=0.003; HR=1.65, P=0.027). Cancer-specific survival (CSS) was not reduced by POCT (HR=1.27, P=0.614), neither in the N2 station negative group (N2(-) group) (HR=0.55, P=0.474), nor in the N2 station positive group (N2(+) group) (P=1.64; P=0.482).Conclusions. POCT after pneumonectomy is safe among carefully selected patients in pIIB-pIIIB NSCLC. Patients who achieved R0 resection probably benefit from POCT in terms of recurrence, but not in cancer-specific survival, particularly in stage pIIIA/pIIIB-N2 patients.