In 13 of 398 patients who underwent hepatectomy, tumor thrombi of the remnant portal vein was concomitantly removed by the balloon catheter method in 8, an open method under hepatic vascular exclusion in 1, and resection of the occlusive portal segment followed by portal reconstruction in 4. In 8 of these patients the liver was cirrhotic. The mode of hepatectomy consisted of bisegmetectomy or trisegmentectomy in 11, segmentectomy in one, and partial resection in one patient. Two patients died of portal thrombosis or hepatic failure in the hospital. The mean survival in four patients was 12 months. Seven are still alive (mean, 16 months). In the corresponding period, nine patients with occlusive tumor thrombi of the portal confluence were hospitalized without operation and survived up to 4 months (mean, 64 days) after detection of the tumoral occlusion. The causes of death of the nine patients were bleeding esophageal varices, rupture of the tumor, or hepatic failure. It was revealed that removal of tumor thrombi in the remnant portal vein contributes to (1) portal decompression, (2) feasibility of arterial embolization, and (3) increase in resectability of the main tumor. At present, this procedure might be regarded as an emergency procedure for the avoidance of the above lethal impendence, but it may open the door to an adjuvant therapy.