Inappropriate mucin production in gall bladder metaplasia and neoplasia--an immunohistological study

This study demonstrates the presence of three antigens in glandular metaplasia occurring in patients with cholecystitis and cholelithiasis: specifically carcinoembryonic antigen (CEA), large intestinal mucin antigen (LIMA) and small intestinal mucin antigen (SIMA). These antigens could not be detected in normal gall bladder mucosa or in squamous metaplasia of the gall bladder. The occurrence of the three intestine-associated antigens in three carcinomas was irregular. In one mucinous carcinoma, only SIMA could be demonstrated. In one adenocarcinoma, SIMA was present in small areas of mucinous change, whilst CEA was present in the non-mucinous malignant tissue. In a mixed mucinous and non-mucinous adenocarcinoma with widespread dissemination, the three antigens were present both in the primary tumour and the metastases. These observations suggest that all forms of glandular metaplasia of the gall bladder are intestinal in nature and at least a proportion of gall bladder carcinomas are of an intestinal type. Finally they provide further immunological evidence that glandular metaplasia of the gall bladder should be considered a pre-malignant condition.