Distal Bile Duct Metastasis after Colorectal Cancer Surgery: A Case Report

Distal bile duct metastasis of colorectal cancer is a rare presentation. The patient was an 82-year-old man who had previously undergone ileocecal resection, partial resection of the stomach, and left hepatectomy for ascending colon cancer, early gastric cancer, and liver metastasis of the colon cancer, respectively, when he was 80 years old. The patient received adjuvant combination chemotherapy of S-1 and oxaliplatin plus bevacizumab. Two years later, during routine follow up, CT scans revealed a high-density tumor with a diameter of 22 mm in the distal bile duct. ERCP also revealed a defect in the distal bile duct, and subsequent biopsy confirmed that the tumor was an adenocarcinoma. Pylorus-preserving pancreaticoduodenectomy (PPPD) was performed based on the diagnosis of distal cholangiocarcinoma. A 35-mm papillary tumor was found in the resected specimen. Pathologically, the tumor was a moderately differentiated tubular adenocarcinoma. The morphology and immunohistochemical staining patterns of the tumor cells were similar to those of the previous colon cancer. Thus, the tumor was strongly suspected to be a bile duct metastasis of the colon cancer. The patient’s recovery following surgery was unremarkable and there has been no recurrence to date.