Malignant Granular Cell Tumor of the Bile Duct

Abstract

A 56-year-old man presented to the emergency department with painless jaundice and weight loss. Abdominal ultrasound detected dilation of the common bile duct and the intrahepatic bile ducts. Follow-up with endoscopic retrograde cholangiography exposed a stricture of the common hepatic duct, with cholangioscopy identifying an infiltrating tumor. Biopsy revealed a granular cell tumor, which was confirmed by positive S-100 immunohistochemical staining. Surgical excision confirmed granular cell tumor of the bile duct with morphological features suggestive of malignancy.