A randomized trial of systematic nodal dissection in resectable non-small cell lung cancer.

Purpose: We conducted a randomized trial to investigate whether systematic nodal dissection (SND) is superior to mediastinal lymph nodal sampling (MLS) in surgical treatment of non-small cell lung cancer (NSCLC).

Methods: The patients resectable clinical Stage I-IIIA NSCLC were randomly assigned to lung resection combined with SND or lung resection combined with MLS. After postoperative pathological re-staging, eligible cases were followed up until 30 November 2000. The Kaplan-Meier method was used for survival analysis. COX proportional hazards model was used for prognostic analysis.

Results: Of the 532 patients who were enrolled in the study, 268 patients were assigned to lung resection combined with SND and 264 were assigned to lung resection combined with MLS. After surgical restaging only 471 cases were eligible for follow-up. The median survival was 59 months in the group given SND and 34 months in the group given MLS (P=0.0000 by the log rank test). There was significant difference in survival in Stage I (5-year survival 82.16 vs. 57.49%) and Stage IIIA (26.98 vs. 6.18%) by the log rank test and Breslow test. There was no significant yet marginal difference in survival by log rank test (10-year survival 32.04 vs. 26.92%, P=0.0523) but significant difference in survival by Breslow test (5-year survival 50.42 vs. 34.05%, P=0.0284) in Stage II. Types of mediastinal lymph node dissection, pTNM stage, tumor size and number of lymph node metastasis were four factors that influenced long-term survival rate by multivariate analysis.

Conclusions: As compared with MLS, lobectomy (pneumonectomy) combined with SND can improve survival in resectable NSCLC.