P648. What is the risk of malignancy at normal appearing mucosa in left-side ulcerative colitis patients?
E. Altintas1, S. Yaras1, F. Ates1, B. Saritas1, M.K. Aydin1, O. Sezgin1, G. Orekici Temel2, E. Üçbilek1, T. Kara3, R. Arpaci3, 1Mersin University Faculty Of Medicine, Gastroenterology Departments, Mersin, Turkey, 2Mersin University Faculty of Medicine, Biostatistic Department, Mersin, Turkey, 3Mersin University Faculty of Medicine, Pathology Department, Mersin, Turkey
Colorectal malignancy risk is increased in ulcerative colitis patients. This risk is parallel with the extent of diseased colon and the duration. Proliferating cell nuclear antigen (PCNA), and Ki67 activities are known as immunohistochemical markers in proliferating cells. We designed a study to evaluate the differences between normal-appearing mucosa and diseased areas in left-side ulcerative colitis patients; in terms of dysplasia development.
Totally 20 consecutive patients enrolled in the study whose surveillance biopsies performed in our clinics with the diagnosis of left side ulcerative colitis. After obtaining informed consent from each patient, a colonoscopy performed and colonic biopsies were taken from the every 10 cms distances from caecum to anal verge. Then, the experienced pathologist investigated the samples according to the presence of inflammation and dysplasia, by means of PCNA and ki67 activities.
For all patients it is observed that, disease activity increased through proximal to distal colonic regions. 12/20 (60%) patients showed mild inflammation in the proximal colonic mucosa samples. No difference found between the normal appearing mucosa and the affected mucosa in terms of ki67 activities (19.3±29.9 versus 23.4±29.09, p = 0.323) and PCNA (39.25±25.922 versus 46.25±27.62, p = 0.332).
The activity of Ki67 and PCNA found to be similar in normal appearing mucosa and the affected mucosa of patients with distal ulcerative colitis, independent of disease activity. This can be explained by the presence of inflammation in normal-appearing mucosa. These results showed that, normal appearing mucosa is affected by disease histopathologically, and has a proliferation potential similar that of the diseased segment, as well.