A 58-year-old man who had gross hematuria and a right upper quadrant mass was found to have a right hypernephroma. Following demonstration of the lesion by renal arteriogram, an inferior vena cavogram demonstrated extension of tumor thrombus from the right renal vein through the inferior vena cava and into the right atrium. Forewarned we prepared for an aggressive surgical approach including cardiac bypass. First we performed segmental resection for a solitary metastasis to the right middle lobe. Then the primary tumor and its extension, including the intracardiac portion, were removed leaving the patient free of gross tumor. The patient recovered promptly and one year later is alive and asymptomatic.