[Evaluation of new TNM classification for lung cancer, especially T3N0M0, stage IIIA, stage IIIB, and pm]

The purpose of this study was to evaluate the results of new TNM staging system for lung cancer in 1997, especially T3N0M0, stage IIIA, stage IIIB, and pm. Five-year survival rates of the patients with stage IIIA and stage IIIB were 16% and 18% respectively (NS). Five-year survival rates of patients with T3N1M0, T1N2M0, T2N2M0, and T3N2M0 were 40%, 28%, 15%, and 3%, respectively. The prognosis of T3N2M0 was significantly worse than that of T3N1M0, T1N2M0, and T2N2M0. Five-year survival rates of the patients excluding pm 1 with T4N0M0, T4N1M0, T4N2M0, and T4N3M0 were 21%, 10%, 10%, and 0%, respectively. The prognosis of the patients with T4N0 was significantly better than that of T4N2 and T4N3. In the patients with pm, 5-year survival rates of the patients with pm 1 and pm 2 were 26% and 7%, respectively (p < 0.01). In the patients with pm 1, 5-year survival rates of the patients with N0 + N1 and N1 + N2 were 53% and 16%, respectively (p < 0.01). From our these results, we supported the new TNM system as putting T3N0M0 to stage IIB, putting pm 2 into stage IV. We proposed; 1) chest wall invasion with bone destruction stay in stage IIIA or is T4, 2) T3N1M0 is classified with stage IIB, 3) main stem bronchus invasion is classified with T2, 4) pm 1 is subdivide by N status. Furthermore, stage III seemed to be reasonably subdivided into T1-2N3M0, T4N0-1M0 as stage IIIA and T3-4N2, T1-4N3 as stage IIIB.