Metastatic lesions in the liver derived from colorectal cancer rarely invade the portal vein macroscopically. Little is known about the clinical characteristics and outcome of surgical treatment in patients with tumor thrombus in the portal vein. Medical charts of 142 consecutive patients who underwent hepatic resection for colorectal metastasis were reviewed retrospectively. Of the 142 patients, 4 (2.8%) had macroscopic portal vein invasion. The most prominent characteristic on preoperative imaging was segmental staining in the arterial phase shown by dynamic computed tomography (CT) or by CT arteriography. This finding was positive in all four of the patients. All patients underwent anatomic liver resection and were alive with no evidence of disease for an average of 52.3 months (range 21-102 months). Macroscopic tumor thrombus in the portal vein is rare with colorectal metastasis. It is accurately detected by CT by checking for signs of segmental staining. In this setting, anatomic major resection of the liver is essential for curative treatment.