DNA aneuploidy in colonic biopsies predicts future development of dysplasia in ulcerative colitis.

The objective of the present study was to determine whether abnormal epithelial DNA content (aneuploidy) in colonic biopsy specimens from ulcerative colitis (UC) patients correlated with and predicted histological progression to dysplasia. Aneuploidy was absent in 20 low-cancer risk patients. In 81 high-cancer risk patients aneuploidy correlated significantly with the severity of histological abnormality (negative, indefinite, dysplasia, or cancer). Statistically our data suggest that many more biopsy specimens than are usually taken are needed to detect focal dysplastic lesions. Prospective study of 25 high risk patients without dysplasia revealed 5 with aneuploidy, all of whom progressed to dysplasia in 1-2.5 years, whereas 19 patients without aneuploidy did not progress to either aneuploidy or dysplasia within 2-9 years. Our data indicate that aneuploidy in mucosal biopsy specimens correlates with histological grade and identifies a subset of patients without dysplasia who are more likely to develop it. It was concluded that more frequent and extensive colonoscopic surveillance of this minority subset of high risk patients and less frequent surveillance in the remaining majority may reduce cost and detect more curable lesions.