Giant cell tumor of the distal common bile duct: report of a rare, benign entity that may mimic malignant biliary obstruction

Undifferentiated Carcinoma with Osteoclast-Like Giant Cells of the Common Bile Duct: A Case Report of a Rare Entity at an Unusual Location

Undifferentiated carcinoma with osteoclast-like giant cells (UCOGC) is a rare variant of carcinoma with unique radiological and pathological features. This unusual carcinoma has been reported in a variety of organs and pancreas is the most frequently involved anatomical site. UCOGC of pancreas attains a relatively indolent clinical behavior and should be distinguished from ordinary pancreatobiliary adenocarcinoma. This paper presents the first case of UCOGC involving the entire segment of common bile duct (CBD) and common hepatic duct (CHD) without extending to the pancreatic tissue. Getting familiar with its clinical, radiological and pathological characters can help establish accurate diagnosis despite the occurrence of an unusual location.

Benign giant-cell tumor of the common bile duct: A case report

Primary giant-cell tumors rarely arise in the common bile duct. We herein report a case of primary giant-cell tumor of the common bile duct. The patient was an 81-year-old male who was diagnosed with a well-defined 1.2-cm mass projecting into the lumen of the middle common bile duct. Excision of the gallbladder and extrahepatic bile duct and a Roux-en-Y cholangiojejunostomy were performed. Histologically, the tumor had no association with carcinomas of epithelial origin and was similar to giant-cell tumors of the bone. The tumor consisted of a mixture of mononuclear and multinucleated osteoclast-like giant cells. The mononuclear cells showed no atypical features, and their nuclei were similar to those of the multinucleated giant cells. CD68 was expressed on the mononuclear and multinucleated osteoclast-like giant cells, whereas CD163 immunoreactivity was restricted to the mononuclear cells. Six months after the operation, the patient was still alive and had no recurrence. The interest of this case lies in the rarity of this entity, the difficulty of preoperative diagnosis, and this tumor’s possible confusion with other malignant tumors.