Granular cell tumor as an unusual cause of obstruction at the hepatic hilum: report of a case.

A diagnosis of malignancy is reasonably assumed when a lesion is found at the hilum or bile ducts in a patient with jaundice who has never undergone biliary surgery. Although benign tumors occasionally develop in this location, preoperative recognition is difficult and most are treated as malignant lesions. We illustrate this clinical scenario in this case report of a granular cell tumor (GCT) that developed at the biliary bifurcation, necessitating right hemi-hepatectomy with extrahepatic biliary tree excision. We describe the clinical presentation, imaging findings, treatment, and histological findings of this tumor. Although rare, a GCT can develop at the hilum and mimic a malignant lesion such as cholangiocarcinoma (CC) radiologically. To our knowledge, this is the fourth report of a GCT at the hilum of the liver. However, the possibility of this tumor should be considered in the differential diagnosis of a lesion in this location.