Clinicopathological features of ulcerative colitis-associated colorectal cancer pointing to efficiency of surveillance colonoscopy in a large retrospective Japanese cohort

Cancer surveillance has been conducted in patients with ulcerative colitis (UC), and the number of operative cases of ulcerative colitis-associated colorectal cancer (UC-CRC) has been increasing. The aim of this study was to clarify the clinicopathological features and prognoses of UC-CRC patients and the relationship between surveillance colonoscopy and UC-CRC. The clinical records of 1,274 UC patients who required surgery between 1984 and 2010 at a single institution were reviewed retrospectively. Of these, 83 patients had CRC (107 sections). All cases were extracted from the database, along with their clinicopathological data. The 5-year survival rate of the UC-CRC group was 89 %. The 5-year survival rate was 100 % in stages 0 and II, 96 % in stage I, 56 % in stage III, and 0 % in stage IV. Surveillance colonoscopy was performed for 40 of the 83 patients. Of 40 patients, 30 with UC who underwent surveillance colonoscopies and 22 of 43 patients without surveillance colonoscopies were in stages 0 to I (P = 0.04). The number of UC-CRC patients who are diagnosed by surveillance colonoscopy is increasing, and many of them are detected in the very early stages (stages 0 or I). Thus, the survival rate of UC-CRC is better than before. Surveillance colonoscopy proofs efficient as CRC are detected in earlier stages.