Clear cell change in colonic polyps.

In this study, the pathogenesis of clear cell change in colorectal epithelial lesions was studied. A total of 4 cases of clear cell change (1 hyperplasic polyp and 3 adenomas) were characterized using histochemistry, immunohistochemistry, and electron microscopy. All lesions developed in the left colon. In all, 1 adenoma with clear cell dysplastic glands progressed to adenocarcinoma without clear cell change. Clear cell cytoplasmatic vacuoles were negative for glycogen and mucins (MUC 2, MUC 5AC). Ki-67 LI in clear cell adenoma components was lower than in common adenoma components of the same dysplasia grades (while p53 and beta-catenin were similarly expressed). Ultrastructural features of clear cell change showed features of lipid-like material. Clear cell change is found in hyperplastic and neoplastic lesions of the colon and is not due to the accumulation of glycogen or mucins. A degenerative nature of clear cell change is suggested by the demonstration of lipid-like material in the vacuoles of clear cells.