The differentiation of true adenomas from colitis-associated dysplasia in ulcerative colitis: a comparative immunohistochemical study.
Adenomas in areas involved by ulcerative colitis (UCA) are difficult to identify because of their morphological similarity to ulcerative colitis-associated dysplasia (UCD) and have an uncertain biology. Recently, a set of morphopathologic criteria were published for the diagnosis of UCA versus UCD. As a first step to analyze these criteria, we studied p53 and bcl-2 expression in groups of UCA and UCD along with a sporadic adenoma control group. Ninety lesions from UC areas (62 patients) were examined, including 24 UCA without high-grade dysplasia (HGD) and 66 UCD consisting of 43 polypoid and 23 flat dysplastic lesions (29 with HGD). Immunohistochemical p53 and bcl-2 expression were evaluated semiquantitatively. P53-positive cases were significantly less frequent in the UCA (4%) versus the UCD group (30%, P = .01) and the polypoid UCD subgroup (35%, P = .005). Moderate or strong bcl-2 expression was significantly more frequent in the UCA than in the UCD group (96% v 70%, P = .01) and in the UCA versus both polypoid and flat UCD subgroups. Comparison of UCA with low-grade dysplastic polypoid UCD cases alone showed a difference just below significance for p53 (P = .07). p53 and bcl-2 expression rates were very similar in the UCA group and the sporadic adenoma (n = 25) control group. These results show that UCA has phenotypic features more similar to sporadic adenomas than UCD and supports the concept that adenomas in UC have a biology different from UC-associated dysplasia.
Mueller
E
E
Institute of Pathology, Klinikum rechts der Isar, Technische Universität München, Munich, Germany.
Vieth
M
M
Stolte
M
M
Mueller
J
J
D000236:Adenoma / Q000209:etiology* / Q000378:metabolism / Q000473:pathology*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003093:Colitis, Ulcerative / Q000150:complications* / Q000378:metabolism / Q000473:pathology*; D018450:Disease Progression; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000096:biosynthesis; D016159:Tumor Suppressor Protein p53 / Q000096:biosynthesis
D019253:Proto-Oncogene Proteins c-bcl-2; D016159:Tumor Suppressor Protein p53