Twenty-year-old stapled pouches for ulcerative colitis without evidence of rectal cancer: implications for surveillance strategy?

Abstract

The risk of anal transition zone dysplasia/cancer after stapled IPAA for ulcerative colitis might be cumulative over time. The purpose of this work was to assess the long-term incidence and risk factors of anal transition zone dysplasia. This was a retrospective study from a prospectively maintained database. The study was conducted at a tertiary referral center. Participants included those in our surveillance program of serial anal transition zone biopsies after stapled IPAA from 1986 to 1992. Anal transition zone dysplasia was the main measured outcome. Of 532 patients, 285 had 2 or more anal transition zone surveillance biopsies, including 73 with ≥20 years of regular follow-up. No adenocarcinoma was detected, and 15 patients died of unrelated causes after a median follow-up of 13.4 years (range, 2.9-19.5 years) without dysplasia. The estimated survival rates at 10, 15, and 20 years were 99.6% (95% CI, 96.9-99.9), 98.9% (95% CI, 95.7-99.7), and 92.6% (95% CI, 86.5-96.0). The estimated rates of anal transition zone dysplasia based on the 9 patients were 2.9% (95% CI, 1.5-5.7) and 3.4% (95% CI, 1.8-6.4) at 10 and 15 years. No new-onset dysplasia was identified beyond 125 months. Postoperative anal transition zone dysplasia was significantly associated with both preoperative and pathology findings of colorectal dysplasia (p < 0.001 for each) or cancer (p = 0.025 and p <0.001) and was managed expectantly or with mucosectomy (5 and 4 patients), depending on the number of positive biopsies and degree of dysplasia. Continued surveillance after detection of anal transition zone dysplasia showed no evidence of recurrent dysplasia during a median follow-up of 125 months (range, 9-256 months). Approximately half of the eligible patients were excluded from the analysis because of insufficient follow-up. Long-term follow-up data corroborate the use of stapled IPAA for ulcerative colitis. Future studies should assess whether a less intensive surveillance strategy is safe 10 years after surgery.