Objective  To investigate the clinicopathological characteristics of lung cancer patients with axillary lymph node metastasis (ALNM).

  Methods  The clinical data of 91 lung cancer patients with ALNM who were treated in Zhejiang Cancer Hospital from January 1st, 2007 to December 31st, 2013 were retrospectively analyzed. The relevance of the sites of the tumor site, local lymph node, and axillary lymph node was checked by contingency table. Survival rates were calculated by the Kaplan-Meier method and compared by a log-rank test. Cox proportional hazards model was applied to analyze the prognostic factors.

  Results  The proportion of lung cancer patients with ALNM was 0.63%, and the patients were often presented with adenocarcinoma, peripheral tumor type, pleura invasion with pleural effusion, or chest wall invasion. A relationship between tumor sites, local lymph node sites, and axillary lymph node sites was observed. The median survival time of lung cancer patients with ALNM was 19.02 months, and the two-year survival rate is 62.64%. Patients identified with ALNM at the initial diagnosis reported poor prognosis (P=0.002). Cox regression analysis showed that the relative risk of death in patients with ALNM at initial diagnosis was elevated 2.18 times (95%CI: 1.330-3.572, P=0.003).

  Conclusion  ALNM in lung cancer is rare, and it may involve through direct chest wall invasion and spread from supraclavicular and mediastinal lymph node metastasis or systemic origin. Patients detected with ALNM at the initial diagnosis indicated poor prognosis.