Survival of patients with resected pIIIa - N2 non small cell lung cancer: suggestion for subclassification

The group of completely resected stage IIIa- N2 non small cell lung cancer (NSCLC) patients is considered heterogeneous in various aspects including survival and pattern of recurrence. The prognostic factors still remain controversial. Clinical trials dealing with multimodal strategy for N2 NSCLC are being watched with keen interest, and the feasibility of this strategy is to be confirmed. In the present study we attempted to clarify the role of different clinicopathological factors which separate patients into high and low- risk groups based on the disease-free and overall survival.

The study comprised 60 consecutive patients with pathologically (p) proven N2 NSCLC who had undergone complete surgical disease resection with curative intent between January 1997 and September 2000. All patients had an apparently resectable disease at preoperative staging and thoracotomy. Extensive mediastinal lymph node dissection was performed when possible and consisted of removal of all ipsilateral mediastinal lymph nodes. Patients were submitted to postoperative split course adjuvant radiotherapy. Cumulative survival rates were calculated by the Kaplan-Meier method. The analyzed prog- nostic factors were age, histological type and grade of differentiation, clinical (c) stage, cN status and tumor size and were tested for statistical significance by univariate analysis using log-rank test and Willcoxon test.

The median follow-up period was 36 months (range 24-72 months). Tumor size, cN status and age were significant predictors of survival. Large tumor size (T3) was significantly worse predictor compared to T1 (p=0.046) and cN2 status evaluated by computed tomography (CT= also showed statistically significant unfavorable prognosis in comparison with cN0 and cN1 (p=0.0185). Patients over 65 years had significantly worse prognosis compared to those under 65 years (p=0.008).

This study identified stage IIIa - N2 NSCLC prognostic subgroups and suggests different therapeutic approach according to the subgroup profile.