Endoscopic screening for dysplasia and mucosal aneuploidy in adolescents and young adults with childhood onset colitis

OBJECTIVES: In adults, the premalignant nature of ulcerative colitis (UC) has long been accepted. Currently there is increasing concern that Crohn's disease (CD) may be equally premalignant. As a consequence, most adults with long-standing UC and many with chronic CD are enrolled in ongoing endoscopic cancer surveillance programs. In contrast, the risk of colonic cancer in adolescents and young adults with either form of colitis is less well recognized, and the need for dysplasia and cancer screening in this population has not been systematically evaluated. We therefore report the prospective results of colonoscopic cancer screening in such a young population. METHODS: Thirty-five adolescents and young adults with long-standing colitis (18 UC, 17 CD; 21 +/- 3 yr old, 11 +/- 3 yr colitis duration) underwent colonoscopic cancer screening. All had multiple biopsies for flow cytometry and light microscopy. RESULTS: Seven subjects had aneuploidy (3/18 UC, 4/17 CD). Of these seven, only two had dysplasia [one high grade (UC), one low grade (CD)]. One additional subject had indefinite dysplasia with normal flow cytometry. The remaining 27 subjects had both normal flow cytometry and light microscopy. Five of the seven aneuploid subjects underwent surgery within 1 yr of screening. Four, including both subjects with dysplasia, had no evidence of colon cancer at surgery. However, a 24-yr-old female with a 14-yr history of UC and no evidence of dysplasia or cancer at screening had a Dukes C adenocarcinoma. CONCLUSIONS: Adolescents and young adults with childhood onset UC or CD are at risk for aneuploidy, dysplasia, and colon cancer. Aneuploidy can be evident 10 yr after the onset of colitis and in patients as young as 16 yr of age. Therefore, the risk for colon cancer in patients with childhood onset colitis must be based on the duration of the illness, not on their chronological age. Incorporation of flow cytometry into an endoscopic screening protocol appears to enhance the ability to identify individuals at highest risk for colon cancer.