[Prognostic Factors of N2 Stage Non-small Cell Lung Cancer after Surgery]

Patients with N2 stage non-small cell lung cancer have prognostic heterogeneity, and this study attempted to explore the prognostic factors among those patients.

Patients with N2 stage undergoing radical resection in Department of Thoracic Surgery, West China hospital, Sichuan University between January 2007 and December 2016 were included. Cox proportional hazard regression model was used to explore the prognostic value of clinicopathological features. Survival curves were plotted by Kaplan-Meier method. Subgroup analyses considering the situation of lymph node involvement were performed.

In total, 773 patients were included. The median follow-up time was 57.2 months, and the 5-year overall survival rate was 34.8%. Tumor-node-metastasis (TNM) stage, number of involved lymph node stations, skip metastasis, lymphatic or vascular invasion and adjuvant chemotherapy were independent prognostic factors. The patients with stage T1-3 had similar prognosis, while the patients with stage T4 had worse survival. In addition, the patients with single station involvement and skip metastasis had the best prognosis with a 5-years overall survival rate of 48.9%.

T4 stage patients had worse survival in N2 group. To get a more precisely stratification, skip metastasis and number of involved lymph node stations should be considered in future N stage classification.