Gallbladder cancer associated with cholesterosis.

We report herein two cases of carcinoma in situ of the gallbladder associated with cholesterosis. The patient in case 1 was an 81-year-old man who underwent a cholecystectomy for cholelithiasis. The resected specimens revealed gallbladder cancer in the fundus which was diagnosed histologically as mucinous carcinoma. Other findings included 13-mm, 12-mm, and 5-mm polypoid lesions in the neck of the gallbladder which macroscopically appeared to be cholesterol polyps, but histologically demonstrated carcinoma in situ with cholesterosis. The patient in case 2 was a 76-year-old man in whom ultrasonography revealed a highly echogenic, elevated lesion in the gallbladder. Cholecystectomy was performed, and a 33 x 28-mm papillary, elevated lesion with cholesterosis was resected from the neck of the gallbladder. Histologically, this was demonstrated to be papillary adenocarcinoma in situ with cholesterosis surrounded by glandular dysplasia. The distribution of the carcinomas and cholesterosis in both of these patients suggests that the adenoma or carcinoma of the gallbladder had occurred first. Then, the tumor epithelium absorbed cholesterol from the bile, and foamy cells were produced. Thus, when treating cholesterol polyps, it should be remembered that it is often difficult to distinguish between cholesterol polyp and gallbladder cancer with cholesterosis.