[Metastases to the mediastinal lymph nodes in lung cancer and their extensive dissection].

OBJECTIVE: To study the metastatic frequency, distribution and feature of mediastinal nodes in lung cancer and to establish criteria for nodal dissection. METHODS: Clinical data of 386 patients who underwent resection of lung cancers in the past 9 years were analyzed retrospectively. Based on the distribution map of mediastinal lymph nodes developed by Naruke, ipsilateral hilar and mediastinal nodes were resected. RESULTS: 147 cases (38.1%) had mediastinal nodal involvement (N2). A total of 289 groups of nodes were dissected. The rate of N2 disease among squamous-cell, adeno-, small-cell and large-cell carcinomas was 30.1%, 44.1%, 48.0% and 50.0%, respectively. In 71 cases with N2 disease in the upper lobes, 146 groups of N2 nodes were resected, including 124 groups in the upper mediastinum (84.9%) and 22 groups in the lower mediastinum (15.1%). In 76 cases with N2 nodes in the lower and middle lobes, 143 groups of N2 nodes were dissected, including 76 groups in the upper mediastinum (53.1%) and 67 groups in the lower mediastinum (46.9%). Saltatory metastases occurred in 79 patients, accounting for 53.7% of N2 nodes and in 16 cases that occurred in the mediastinum (10.9%). CONCLUSION: The feature of mediastinal lymph node metastases in lung cancer may be saltatory and multiple. Cure can be achieved only after extensive dissection of the upper and lower mediastinal nodes.