Carcinoma in situ of the cystic duct

Cholelithiasis and cholesterolosis associated with carcinoma in situ of the cystic duct epithelium was observed in a male patient. Ultrastructurally, small acini-like lined a thickened, reduplicated basal lamina encompassing a pleiomorphic population of cells, including typical cholecystocytes, a poorly differentiated type, and cells containing modified mucous vesicles with heterogeneous fatty deposits. Even though the etiology of this apparent neoplastic epithelium and of its thickened basal lamina is unclear, it is hypothesized to be the result of an altered control of cell adhesion mechanisms, resulting from a repeated renewal of the typical epithelium abraded by the passage of the stones and the biliary sludge, associated with inflammatory stimuli that accompany cholecystolithiasis. Based on recent studies, it is suggested that investigations of molecular markers in extrahepatobiliary tract lesions and retrospective studies of these archival tissues could clarify the association of these neoplastic changes with other hepato-biliary lesions.