Clinical analysis on characteristics of lymph node metastasis in lung cancer

Objective To investigate the characteristics and patterns of lymph node metastasis in lung cancer and to provide evidence for determining the range of lymph node dissection.Methods One hundred and eighteen patients with lung cancer received complete resection combined with systematic lymph node dissection according to the mapping system developed by Naruke.Results A total of 835 lymph nodes were dissected from 118 lung cancer patients.The positive ratios of N1 and N2 were 15.6% and 17.4% respectively.Fifteen patients were found with skipping N2 which were located in 2,4,5,6 and 7 lymph node groups respectively.There was no significant relationship between the size of primary tumor and lymph node metastasis.Small cell lung cancer showed the highest risk of lymph node metastasis.The metastatic rate of lymph node in adenocarcinoma was markedly higher than that of squamous cell carcinoma.Skipping mediastinal lymphatic metastasis was found more frequently in lower lobar tumors than that in upper lobar ones.Conclusion Lymph node metastasis of lung cancer may occur in multiple groups and regions,even in a skipping pattern.Systematic lymph node dissection may be routinely performed in pulmonary resection for lung cancer.