Surgical results and staging of non-small cell lung cancer with interlobar pleural invasion.

The aim of this study was to compare the survival rates of non-small cell lung cancer (NSCLC) with interlobar pleural invasion (IPI) with that of patients with other T2 and T3 diseases according to the seventh TNM staging system. One thousand and one patients with pathologic T2 and T3 NSCLC (according to the seventh staging criteria) treated between 1980 and 2004 were retrospectively evaluated. Among these, 682 patients were pathologically staged as T2 without IPI (T2 group), 25 as T2 with IPI (IPI group) and 294 as T3 (T3 group). The 5-year survival rate for the T2, IPI and T3 groups were 52.0, 31.1 and 36.3%, respectively. In patients without nodal involvement, the 5-year survival rates of the T2N0, IPIN0 and T3N0 groups were 60.9, 40.0 and 45.9%, respectively. The survival rate was significantly different between the T3N0 and T2N0 groups (P < 0.001) and between the IPIN0 and T2N0 (P = 0.020) groups. There was no significant difference in the survival rate between the IPIN0 and T3N0 groups (P = 0.644). In patients without nodal involvement, the survival of NSCLC with IPI is similar to that of the T3 disease.