Results of surgical treatment of non-small cell lung cancer: Validation of the new postoperative pathologic TNM classification

Objective: Prognostic relevance of the current TNM stage grouping for lung cancer is still a matter of debate. Methods: To validate the new pathologic TNM classification for non-small cell lung cancer, we analyzed the survival data of 586 patients who underwent complete pulmonary resection and pathologic staging at one institution. Results: The current TNM stage grouping well reflected the long-term prognostic hierarchy. There was a good distinction between new substages IA and IB (5-year survivals of 66% and 53%, respectively). The subdivision of stage II led to an under-representation of stage IIA (6 patients [1.0%]), and therefore the appropriateness of this modification could not be verified. Five-year survival in the T3 N0 category (30%) was significantly better than that found in the new stage IIIA (15%). No difference was found between T3 NO and T2 N1, the categories constituting new stage IIB. Within stage IIIA there was a significant survival difference between T3 N2 (6%) and the remaining T and N designations (18%). Moreover, the 5-year survival in the T3 N1 category (35%) was similar to that found in the new stage LIE (27%) and better than in any T N2 tumors (12%). Conclusion: Most of our findings confirmed prognostic relevance of the current pTNM stage grouping in patients with resectable non-small cell lung cancer. However, despite recent modifications, there is still a significant heterogeneity that flaws stage IIIA.