Hilar and mediastinal lymph node metastases in malignant melanoma.

Of 65 patients with intrathoracic metastases from melanomon, 35 had metastasis to hilar or mediastinal nodes. In 28 of these 35, hilar and mediastinal lymph node enlargement was radiographically visible, hilar node enlargement was more commonly seen than mediastinal node enlargement. Pulmonary nodules were demonstrated radiographically in 25 of the 28 patients. Although lymph node enlargement was often asymmetric, symmetric hilar adenopathy mimicking sarcoidosis occurred in five of the 28 patients. Seven patients had unilateral involvement of lung and hilar and mediastinal nodes. In patients with melanoma, indirect metastatic spread via pulmonary nodules to hilar and mediastinal nodes may account for the frequent association of node metastases with lung nodules, the occurrence of intrathoracic adenopathy in the absence of extrathoracic node metastases, and the common finding of unilateral lung and nodal disease.