Validation of 7th TNM staging system for lung cancer, based on surgical outcomes

Abstract

Validation of the clinical classification for lung cancer of the 7th edition of the TNM staging system among surgical cases has not been reported previously. Data of 489 males and 246 females, with a mean age of 67.6 years, who underwent surgical resection for non-small-cell lung cancer were analyzed retrospectively. The 5-year survival rate of these patients was 72.2% for clinical stage IA (n = 365), 58.4% for IB (n = 158), 51.2% for IIA (n = 77), 49.1% for IIB (n = 42), 36.8% for IIIA (n = 86), 80% for IIIB (n = 5) and 50% for IV (n = 2). The 5-year survival rate of patients was 100% for pathological stage 0 (n = 2), 86.1% for IA (n = 216), 73.8% for IB (n = 173), 46.1% for IIA (n = 97), 47.2% for IIB (n = 69), 33.3% for IIIA (n = 155), 33.3% for IIIB (n = 3) and 30.9% for IV (n = 20). Prognostic factors included female sex and 70 years of age or younger, as well as adenocarcinoma histology. Deterioration in patient survival was indicated with the exception of stages IIIB and IV, each of which included only a small number of patients. Our study validated the current TNM staging system in surgical cases with regard to both clinical and pathological classifications.