Background: Postoperative prognosis for patients with pathologic (p-) stage IIIA-N2 non-small-cell lung cancer (NSCLC) is poor, and significant factors that influence the prognosis remain unclear.
Methods: A total of 99 patients who underwent complete resection for p-stage IIIA-N2 NSCLC without any preoperative therapy were retrospectively reviewed. Biological features such as tumor angiogenesis (intratumoral microvessel density [IMVD]), proliferative activity (proliferative index [PI]), and p53 status were also evaluated immunohistochemically.
Results: Univariate analysis revealed that the number of involved N2 stations was a significant prognostic factor; 5-year survival rates for a tumor with metastases in single N2 stations, tumor with metastases in two N2 stations, and tumor with metastases in 3 or more N2 stations were 41.6%, 35.3%, and 0.0%, respectively (P =.041) In addition, the 5-year survival rate for cN0-1 disease was significantly higher than that for cN2 disease (41.9% and 25.5%, respectively; P =.048) Tumor angiogenesis and proliferative activity were the most significant prognostic factors; 5-year survival rates for lower-IMDV tumor and higher-IMVD tumor were 53.6% and 15.9%, respectively (P =.002), and those for lower-PI tumor and higher-PI tumor were 47.0% and 20.4%, respectively (P =.019) There was no difference in the postoperative survival between tumor showing aberrant p53 expression and tumor showing no aberrant p53 expression. These results were confirmed by a multivariate analysis.
Conclusions: P-stage IIIA-N2 NSCLC cases represented a mixture of heterogeneous prognostic subgroups, and the number of involved N2 stations, cN status, PI, and IMVD were significant predictors of the survival.