A case of sigmoid colon cancer with synchronous bile duct metastasis which was difficult in differential diagnosis of intrahepatic cholangiocarcinoma

Abstract

A 74-year-old man who underwent Sigmoidectomy due to Sigmoid colon cancer in October 2018 was introduced to our hospital because of left intrahepatic bile duct dilation. Enhanced CT scan revealed the intrahepatic bile duct dilation and the enhanced mass in junction of B4. MRCP revealed the obstruction in junction of B4. Peroral cholangioscopy (POCS) showed the papillary mass in junction of B4 to left hepatic duct and the biopsy revealed class V. The operation was performed with diagnosis of intrahepatic cholangiocarcinoma on January 2019. We recognized the small white mass on the liver surface during the surgery and judged as liver metastasis of sigmoid colon cancer. All lesions were limited in the liver left lobe and the intraoperative frozen section revealed that the resection stump of left bile duct was cancer negative, so the left lobectomy was performed. Histopathological findings were adenocarcinoma and Cytokeratin (CK) 7 (-), CK20 (+), CDX2 (+) in the both lesion of bile duct and liver, so the origin was colorectal cancer. The diagnosis was sigmoid colon cancer with synchronous bile duct and liver metastasis.