Xanthogranulomatous cholecystitis. A clinicopathological study of 20 cases and review of the literature.

Xanthogranulomatous cholecystitis (XGC) is a focal or diffuse destructive inflammatory process of the gall bladder, characterized macroscopically by yellowish tumour-like masses in the wall of the gall bladder. Microscopically, it is characterized in the early stages by a large number of foamy histiocytes and acute inflammatory cells. Later stages demonstrate increasing fibrosis. The gall bladder from 20 of 352 consecutive patients subjected to cholecystectomy showed XGC. Gall stones were found in the gall bladder of all 20 patients and in the ductus choledochus in 3 cases. Perforation of the gall bladder was observed at operation in six cases; in one case there was also a fistula to the colon. A perivesical abscess was found in five other cases. Adhesions to the surrounding structures were seen in a total of 16 cases. Pathogenetically, XGC is probably due to an interplay between obstruction of the gall flow, infection with subsequent inflammation, and leakage of gall fluid to the tissue, where histiocytes accumulate and phagocytize the bile pigment, haemosiderin and cholesterol, resulting in the formation of xanthoma cells. The correct diagnosis of XGC is important for several reasons, first and foremost due to the high frequency of complications, but not least because the condition may give rise peroperatively to the suspicion of malignancy. The new laparoscopic method for cholecystectomies further stresses the necessity of correct preoperative diagnosis of complicating disease.