Extrahepatic bile duct metastasis from rectal adenocarcinoma: case report and literature review.

INTRODUCTION AND IMPORTANCE: Extrahepatic metastasis is an exceptional site for rectal adenocarcinoma. Its clinical and radiological presentations are similar to those of cholangiocarcinoma, and its management requires collaboration between surgeons, endoscopists, and oncologists.

CASE PRESENTATION: We present a unique case of a 58-year-old woman previously treated two and a half years ago for middle rectal adenocarcinoma with liver metastasis. In the immediate postoperative period, following restoring digestive continuity, she presented cholestatic jaundice from malignant obstruction of the extrahepatic bile duct. A midline laparotomy revealed a tumor of the common bile duct invading the hepatic pedicle. Therefore, external bile drainage, biopsy and hepatic lymph node dissection were performed. Immunohistochemical staining confirmed the diagnosis of extrahepatic bile duct metastasis from rectal adenocarcinoma.

CLINICAL DISCUSSION: Extrahepatic bile duct metastasis from rectal adenocarcinoma manifests as bile duct stenosis or intraluminal lesions, and only pathological examination with immunochemical staining confirms the diagnosis. Radical treatment is possible when general conditions allow it.

CONCLUSION: Our case is the twelfth to describe a solitary metastasis of the bile duct metastasis from colorectal adenocarcinoma. The rarity of published cases in the literature means that their development mechanism and management are not well-codified.