Size of Stage IIIA Primary Lung Cancers and Survival: A Surveillance, Epidemiology and End Results Database Analysis

Abstract

Size of early-stage lung cancer is important in the prognosis of patients. We examined the large population-based Surveillance, Epidemiology and End Results database to determine if tumor size was an independent risk factor of survival in patients undergoing lobectomy for N2 positive Stage IIIA nonsmall cell lung cancer (NSCLC). This study identified 1971 patients diagnosed with N2 positive Stage IIIA NSCLC, from 1998 to 2007, and who underwent lobectomy. Five tumor groups based on the seventh edition TNM lung cancer staging system (pathologic T1a 2 cm or less; T1b greater than 2 cm and 3 cm or less; T2a greater than 3 cm and 5 cm or less; T2b greater than 5 cm and 7 cm or less; T3 greater than 7 cm) were analyzed. Survival was reduced in patients with T3, T2a, and T2b tumors compared with patients with T1a and T1b (P < 0.001). Survival estimates correlated with tumor size with poorer survival in T3 followed by T2b, T2a, and then T1b and T1a. Cohorts with T1a (hazard ratio [HR], 0.53; P = 0.01) and T1b (HR, 0.54; P = 0.01) were both found to have decreased hazard of death. Negative predictors of survival, in addition to increasing tumor size, included age and male gender, whereas positive predictors included tumor Grade I and upper lobe location. Increasing size of tumor is an independent negative risk factor for survival in patients undergoing lobectomy for N2 positive Stage IIIA NSCLC.