Low incidence of asymptomatic brain metastases in patients with renal cell carcinoma. Brain metastases from renal cell carcinoma are uncommon. The present study was undertaken to determine the value of routine computerized tomographic (CT) scanning of the brain in patients with renal cell carcinoma. A review of 106 patients with renal cell carcinoma who had undergone CT scan of the brain revealed brain metastases in only 13.2 percent. Brain metastases were accompanied by central nervous system (CNS) symptoms in 78.6 percent of patients, with headaches constituting the most common presenting symptom (64.3%). Brain metastases were detected in only 3.3 percent of patients who had no CNS symptoms at the time of evaluation. It is concluded that CT scanning of the brain should be performed routinely only for those patients who report CNS symptoms at the time of evaluation. 