Xanthogranulomatous cholecystitis. Histopathological study and classification.

Xanthogranulomatous cholecystitis (XC) is a chronic inflammatory lesion of the gallbladder histologically characterized by the presence of varying amounts of foamy histiocytes in the inflammatory infiltrate. In this study a review of 63 cases selected from 1207 surgically removed gallbladder is presented; the percentage found (5.2%) is slightly higher than that of previous reports showing that XC is less uncommon than generally believed. A detailed microscopic study is performed: the authors observed according to the histological features particularly the different patterns of distribution of the inflammatory infiltrate and postulate the existence of three subtypes of XC: multinodular, focal and diffuse XC. Finally, the main etiopathogenetic hypotheses are briefly discussed.