Pulmonary embolism-the initial manifestation of renal cell carcinoma in a young woman.

We report a case of massive pulmonary embolus demonstrated on CT in a young woman presenting with dyspnea, with no known risk factors for embolism. Abdominal CT on further investigation showed a renal tumor invading the left renal vein and the inferior vena cava as the cause of the pulmonary embolus. In a patient presenting with pulmonary artery embolism without venous thrombosis, the differential diagnosis should include an occult tumor as the cause of the embolus.