Granular Cell Tumor of the Gallbladder: A Rare Entity.

Background/Aim: Granular cell tumor (GCT) is a rare, typically benign neoplasm most likely derived from Schwann cells. GCTs occur in the biliary tract in less than 1% of cases, with the gallbladder being the least common location for this tumor. Case Report: We report a case of a 37-year-old female who presented with persistent biliary colic. Histopathological analysis revealed a polypoid lesion in the gallbladder composed of large polygonal cells with abundant, eosinophilic, granular cytoplasm. Immunohistochemical staining showed positivity for S-100, SOX10 and focally positive for CD68 confirming the diagnosis of a benign GCT. Conclusion: GCT of the gallbladder is an exceptionally rare entity, with this representing only the tenth reported case in the literature. These tumors frequently mimic more common conditions such as cholecystitis, often presenting as biliary colic. Despite its rarity, GCT should be included in the differential diagnosis of gallbladder lesions, especially in younger populations.