Intracardiac Wilms' tumor: diagnosis and management.

Complete excision of Wilms' tumor may require resection of adjacent organs and removal of intracaval tumor propagation. Extension of tumor to the right atrium can be determined preoperatively guiding a direct and safe approach to intracardiac tumor at the time of nephrectomy. Preoperative ultrasonography of two children with Wilms' tumor demonstrated caval and right atrial tumor. Laparotomy for nephrectomy and abdominal caval exposure was combined with cardiopulmonary bypass and atriotomy. In both patients, tumor contiguous with the renal pelvis extended from the iliac bifurcation into the right atrium with a large atrial mass. In one patient nephrectomy was performed first, and she was then placed on cardiopulmonary bypass. Caval tumor was easily removed through the atriotomy and open renal vein. In the second patient, bypass was instituted first because of cardiac instability. The large right atrial mass extended through an atrial septal defect into the left atrium. The cardiac tumor and a large amount of caval tumor were removed. Bypass was discontinued after repair of the ASD. Tumor remained in the IVC below the renal veins necessitating a separate venotomy. Combined abdominal and cardiac exploration allows safe and complete excision of all gross tumor. Ultrasonography is a sensitive and noninvasive method of diagnosing retrohepatic and atrial tumor extension and can be obtained easily even on very sick patients.