Effect of mediastinal lymph nodes sampling in patients with clinical stage I non-small cell lung cancer

Objective : Systematic nodal dissection has been recommended for patients with resectable non-small cell lung cancer because of its staging accuracy. However, in patients with clinical stage I non-small cell lung cancer whether systematic nodal dissection provides more benefits than mediastinal lymph node sampling or not is controversial. In this retrospective study, we evaluated the effect of mediastinal lymph node sampling in patients with clinical stage I NSCLC. Methods : One hundred and nineteen consecutive patients with clinical stage I NSCLC, who underwent curative operation between January 1994 and December 2000, were retrospectively reviewed (dissection group = 58 : sampling group= 61). Systematic nodal dissection was defined as complete removal of mediastinal lymph node, and mediastinal lymph node sampling was defined as removal of lymph node levels 3, 4, and 7 for right-sided tumors and levels 5, 6, and 7 for left-sided tumors. Results : The total number of removed mediastinal lymph nodes in patients who underwent systematic nodal dissection was 22.1 +/- 9.7, which was significantly higher than that in patients who underwent mediastinal lymph node sampling of 11.4 +/- 7.0 (p < 0.001). Postoperatively N2 disease was detected in 8 patients (13.8%) in the dissection group and 7 (11.5%) in the sampling group. After the median follow up of 79 months, the cancer specific survival rate at 5 year was 78.0% in the dissection group and 76.2% in the sampling group (p = 0.60). Conclusions : Mediastinal lymph node sampling showed the similar effect to systematic nodal dissection in patients with clinical stage I non-small cell lung cancer.