Incidence and distribution of intrathoracic metastases from renal cell carcinoma.

Chest roentgenographic findings in 46 patients with renal cell carcinoma were analyzed and correlated to clinical and pathologic findings. Twenty-five patients (54.3%) had intrathoracic metastasis, 17 (37%) of whom had roentgenographic evidence of intrathoracic metastasis at the time of initial diagnosis. Lung metastasis was present in 14 patients (30%), alone in ten patients and along with mediastinal or pleural metastasis in four patients. Mediastinal lymph node metastasis was present in 13 patients (28.2%) and was distributed in the following locations: bilateral hila, six; right hilum, two; right paratracheal area, two; left hilum, one; left paratracheal area, one; and left hilum and right paratracheal area, one. Mediastinal lymph node enlargement was the sole roentgenographic finding in six patients (13%). Metastasis to the lungs or mediastinum may already be present in more than a third of the patients with renal cell carcinoma at the time of diagnosis. Mediastinal lymph node metastasis from renal cell carcinoma occurs more frequently than previously reported and may be the only chest roentgenographic manifestation of the disease.