Survival impact of pN2a and pN2b nodal status in stage IIB-IIIB non-small cell lung cancer under the 9th TNM classification

Background: Surgical resection in non-small cell lung cancer (NSCLC) is a potentially curative option in selected patients.Current TNM staging systems emphasize the prognostic role of pathological N (pN) status, and in the 9 th TNM system pN2 disease is subdivided into single-(pN2a) and multiple-station (pN2b) N2 involvement.This study aimed to evaluate the impact of nodal status and other prognostic factors on survival in patients with stage IIB-IIIB NSCLC reclassified according to the 8 th and 9 th TNM systems.Methods: A total of 824 patients aged ≥18 years who underwent lung resection for NSCLC between 2007 and 2021 and were stage IIB, IIIA, or IIIB according to the 8 th TNM system were included.Demographic, histopathologic, surgical, and survival data were retrospectively analyzed.All cases were restaged according to both the 8 th and 9 th TNM criteria, and the effects of lymph node status and pathological factors on survival were investigated.Results: The mean age was 59.7±8.58 years; 10.4% of patients were female.Squamous cell carcinoma (61.7%) and adenocarcinoma (32.5%) were the most common histologies.Lobectomy, pneumonectomy, and segmentectomy were performed in 52.3%, 46.8%, and 0.8% of patients, respectively.Age >70 years (p