Recurrence of mucosal carcinoma of the bile duct, with superficial flat spread, 12 years after operation.

We report herein a case of recurrent mucosal cancer of the extrahepatic bile duct, with superficial flat spread, 12 years after operation. A 67-year-old woman had undergone common bile duct (CBD) resection and Roux-en-Y reconstruction. Histologically, the tumor was papillary adenocarcinoma, with superficial flat spread, with no invasive component. The epithelium at the distal margin had been exfoliated, so the absence or presence of any remnant cancerous lesion was unclear. But the superficial flat spread had expanded to within at least 3 mm from the distal margin. About 12 years postoperatively, she was hospitalized with upper abdominal pain, and duodenoscopy demonstrated a tumor in the second portion of the duodenum. Biopsy identified adenocarcinoma. Computed tomography showed a low-density mass between the duodenum and pancreatic head. Pancreatoduodenectomy was performed. Histologically, papillary adenocarcinoma was found within the whole of the intrapancreatic bile duct, and its histological appearance resembled that of the original tumor. Moderately differentiated tubular adenocarcinoma had invaded around the tissue of the intrapancreatic CBD. These findings suggest that remnant intramucosal flat carcinoma within the intrapancreatic bile duct had developed into invasive carcinoma over the course of 12 years. This case suggests that remnant intraepithelial flat carcinoma within the CBD may develop a late local recurrence.