Intestinal obstruction caused by colonic metastasis from intrahepatic cholangiocarcinoma 6 years after removal of the primary tumor: report of a case

We report a case of intestinal obstruction caused by metastasis that manifested 6 years after surgery for intrahepatic cholangiocarcinoma (ICC). The patient, a 57-year-old man, had undergone resection of the hepatic left lobe, Spiegel lobe, and extrahepatic bile duct, following which histopathological examination had confirmed the diagnosis of ICC and that the resection margins were free from disease. There had been no signs of recurrence until an increase in the CA19-9 level was detected 6 years later. Colonoscopy revealed an ulcer-like lesion and stenosis at the level of the hepatic flexure. The patient was subsequently admitted to our hospital with abdominal pain and underwent right hemicolectomy with partial resection of hepatic segment V. Based on the immunohistological finding that the expression pattern of cytokeratins and mucins was consistent with ICC origin rather than colon cancer origin, we diagnosed colon metastasis from ICC.