Prognostic factors in resected T3 non-small cell lung carcinoma: perineural invasion as a new prognostic factor

Currently the best prognostic indicator for resected non-small cell lung cancer (NSCLC) is the TNM stage. Moreover, certain histopathological properties of the tumor (such as lymphatic, vascular and perineural invasion) can help to predict the survival of the patients.

Between 1997 and 2004, the results of surgical treatment were retrospectively analyzed for 153 patients with T3 non-small cell lung cancer. One hundred and twenty-four of them had had complete (R0) resections, and 29 had had incomplete (R1) resections. The prognostic factors evaluated by univariate and multivariate analysis were: type of resection; N status; subgroup of pT3; effect of adjuvant therapy; tumor size; histological type; tumor differentiation; lymphatic invasion; vascular invasion; and perineural invasion.

The overall 5-year survival rate was 32 % in R0 patients, and 8 % in R1 patients ( P = 0.0002). The presence of N2 disease, vascular invasion, and perineural invasion were found to be significant prognostic indicators in univariate analysis ( P = 0.0058, P = 0.033, and P = 0.0058, respectively). Among these indicators, N2 disease and perineural invasion were also found to be significant prognostic factors in multivariate analyses ( P = 0.013, and P = 0.003, respectively).

Incomplete resection, N2 disease, vascular and perineural invasion were found to be prognostic indicators for the survival of T3 NSCLC patients. Of these indicators, perineural invasion was found to be the strongest predictor of poor prognosis and independently affected the patients' survival.