PERIPHERAL CHOLANGIOCARCINOMA OF THE LIVER - 2-PHASE SPIRAL CT FINDINGS

PURPOSE: To determine characteristic features of peripheral cholangioc arcinoma on two-phase spiral computed tomographic (CT) scans. MATERIAL S AND METHODS: Thirty-four patients with peripheral cholangiocarcinoma underwent two-phase spiral CT. Hepatic arterial phase and portal veno us phase images were obtained 30 and 65 seconds, respectively, after t he start of contrast material infusion. RESULTS: Thin, mild, incomplet e rimlike contrast enhancement at the tumor periphery was seen on CT s cans from both phases in 23 patients. Thick, continuous rimlike contra st enhancement and marked homogeneous contrast enhancement were presen t on scans in four patients and one patient, respectively, No definite contrast enhancement pattern was seen on scans in six patients. Other findings included increased lobar or segmental hepatic attenuation in adjacent normal liver during the arterial phase (n = 10), markedly lo w attenuation with amorphous areas of slightly high attenuation in the tumor during both phases (n = 33), internal septumlike linear structu res (n = 8), narrowing or obstruction of the portal vein as it travers ed the tumor (n = 16), and a patent hepatic vein (n = 4). CONCLUSION: Thin, mild, incomplete rimlike contrast enhancement at the tumor perip hery and markedly low intratumoral attenuation with amorphous areas of slightly high attenuation during both scanning phases are typical fin dings of peripheral cholangiocarcinoma.