Original Article
Clinical significance of skipping mediastinal lymph node metastasis in N2 non-small cell lung cancer
Abstract
Background: Lymph node metastasis is critical for the prognosis of non-small cell lung cancer (NSCLC) patients, and understanding of the pattern of lymph node metastasis is key to the treatment. We aim to investigate the N2 NSCLC patients without N1 lymph node involvement.
Methods: From 1999 to 2005, a total of 803 patients with pN2 NSCLC were enrolled in this study. Among them, 137 pN2 patients with no metastasis at the hilar (N1) lymph nodes [skip (+) group] were compared with the other 666 patients [skip (−) group].
Results: The percentage of male, smoker and squamous cell carcinoma patients were significantly higher in the skip (+) group, (83.21% vs. 64.11%, P<0.001; 76.64% vs. 53.60%, P<0.001; 50.36% vs. 37.54%, P=0.007, respectively). Also, the primary tumor of skip (+) group patients were significantly more often located in the right upper and middle lobe (43.07% vs. 23.42%, 10.95% vs. 4.05%, P=0.001), and metastasis more frequently involved one lymph node station (75.18% vs. 49.55%, P<0.001). There was no significant difference in the number of total and N2 lymph node dissected. The postoperative survival of patients in both groups were also similar (P=0.379).
Conclusions: Skipping mediastinal lymph node metastasis happens in about 17% of NSCLC patients with mediastinal lymph nodes metastasis but it is not a prognostic factor.
Methods: From 1999 to 2005, a total of 803 patients with pN2 NSCLC were enrolled in this study. Among them, 137 pN2 patients with no metastasis at the hilar (N1) lymph nodes [skip (+) group] were compared with the other 666 patients [skip (−) group].
Results: The percentage of male, smoker and squamous cell carcinoma patients were significantly higher in the skip (+) group, (83.21% vs. 64.11%, P<0.001; 76.64% vs. 53.60%, P<0.001; 50.36% vs. 37.54%, P=0.007, respectively). Also, the primary tumor of skip (+) group patients were significantly more often located in the right upper and middle lobe (43.07% vs. 23.42%, 10.95% vs. 4.05%, P=0.001), and metastasis more frequently involved one lymph node station (75.18% vs. 49.55%, P<0.001). There was no significant difference in the number of total and N2 lymph node dissected. The postoperative survival of patients in both groups were also similar (P=0.379).
Conclusions: Skipping mediastinal lymph node metastasis happens in about 17% of NSCLC patients with mediastinal lymph nodes metastasis but it is not a prognostic factor.
