Ki-67 and p53 expression in ileal pouches.

Development of dysplastic lesions that may potentially lead to cancer is sometimes reported within the ileal pouches. Dysplasia is in turn associated with increased expression of proliferation indices. The goal of this study was to evaluate the mitotic activity and possible expression of p53 in the epithelium within the ileal pouches in patients with chronic ulcerative colitis. The study involved archive material consisting of ileal pouches surgically removed from 17 patients diagnosed with ulcerative colitis. Several specimens were collected from each pouch. The immunohistochemistry (Ki-67 and p53 protein) control group (14 cases) consisted of the resection line specimens of colons removed due to colorectal adenocarcinoma. Intensity of the expression of the markers under study within the inflammatory infiltrates was assessed using a 5-point scale proposed by Berstein et al. Ki-67 expression was observed in all studied patients with marked intensity (Bernstein scale score +3, +4). Protein p53 expression was observed only in eight patients, and was mostly of low intensity (Bernstein scale score +1, +2). Immunohistochemical results confirmed the histopathological results that revealed dysplastic lesions, which are often an indication for radical procedures in ulcerative colitis patients. Our results suggest the usefulness of these examinations, also in the ileal pouch material.