Effectiveness of radical systematic mediastinal lymphadenectomy in patients with resectable non-small cell lung cancer: results of a prospective randomized trial.

OBJECTIVE: To evaluate the effectiveness of lymphadenectomy in the treatment of non-small cell lung cancer (NSCLC).

SUMMARY BACKGROUND DATA: The extent of lymphadenectomy in the treatment of NSCLC is still a matter of controversy. Although some centers perform mediastinal lymph node sampling (LS) with resection of only suspicious lymph nodes, others recommend a radical, systematic mediastinal lymphadenectomy (LA) to improve survival and to achieve a better staging.

METHODS: In a controlled, prospective, randomized clinical trial, the effects of LA on recurrence rates and survival were analyzed, comparing LS and LA in 169 patients with operable NSCLC.

RESULTS: After a median follow-up of 47 months, LA did not improve survival in the overall group of patients (hazard ratio: 0.78; 95% confidence interval: 0.47-1.24). Although recurrences rates tended to be reduced among patients who underwent LA, these decreases were not statistically significant (hazard ratio: 0.82; 95% confidence interval: 0.54-1.27). However, analysis of subgroups of patients according to histopathologic lymph node staging revealed that LA appears to prolong relapse-free survival (p = 0.037) with a borderline effect on overall survival (p = 0.058) in patients with limited lymph node involvement (pN1 disease or pN2 disease with involvement of only one lymph node level); in patients with pN0 disease, no survival benefit was observed.

CONCLUSIONS: Radical systematic mediastinal lymphadenectomy does not influence disease-free or overall survival in patients with NSCLC and without overt lymph node involvement. However, a small subgroup of patients with limited mediastinal lymph node metastases might benefit from a systematic lymphadenectomy.