Is lobe specific lymph node dissection adequate for cN0–1 non-small cell lung cancer?

PURPOSE: This study aims to explore whether lobe specific lymph node dissection (LND) is adequate for cN0–1 non-small cell lung cancer (NSCLC) or not. METHODS: Among 5613 cN0–1 NSCLC patients, 394 cases (7.0%) with pN2 were enrolled and the distribution of mediastinal lymph node metastasis was analyzed. The included patients were divided into the non-lobe specific lymph node metastasis (NLSLNM) group and the lobe specific lymph node metastasis (LSLNM) group. The clinicopathological characteristics were compared between two groups and multivariable analysis was performed to find independent factors predicting NLSLNM. RESULTS: The incidence of pN2 cases deserved serious attention. The proportion of upper zone lymph node metastases was not rare in right (55.0%) and left (35.7%) lower lobe tumors. The proportion of subcarinal zone lymph node involvement was also high in right (21.8%) and left (25.8%) upper lobe tumors. Multivariable analysis showed that elevated carcinoembryonic antigen (CEA) level (P = 0.034), right lower lobe (RLL) tumors (P = 0.022) and station 11 involvement (P = 0.030) were independent risk factors for NLSLNM. CONCLUSION: Systematic LND seems to be superior to lobe specific LND in the assessment of lymph node status and high CEA level, RLL tumors and station 11 involvement are predictors for NLSLNM.