Five-year risk for advanced colorectal neoplasia after initial colonoscopy according to the baseline risk stratification: a prospective study in 2452 asymptomatic Koreans. Issue 11 (22nd March 2011)

• Record Type: Journal Article
• Authors: Chung, Su Jin; Kim, Young Sun; Yang, Sun Young; Song, Ji Hyun; Kim, Donghee; Park, Min Jung; Kim, Sang Gyun; Song, In Sung; Kim, Joo Sung
• Is Part Of: Gut. Volume 60:Issue 11(2011)
• Page Start: 1537
• Page End: 1543
• Publication Date: 2011-03-22
• Subjects: Colorectal neoplasia -- surveillance -- colonoscopy -- recurrence -- risk factor; Gastroenterology -- Periodicals; 616.33
• DOI: 10.1136/gut.2010.232876
• Languages: English
• ISSNs: 0017-5749

Abstract

Abstract : Objective: Postpolypectomy surveillance guidelines for colorectal cancer introduced the concept of 'risk stratification'; however, few studies have been conducted for validation of its usefulness. The aim of this study was to assess the 5-year incidence of advanced neoplasia recurrence based on the risk stratification scheme of the guidelines and to identify its risk factors. Methods: A prospective study of surveillance colonoscopy after screening colonoscopy was carried out at the Seoul National University Hospital Healthcare System Gangnam Center. 3803 asymptomatic Koreans aged 50–69 were enrolled prospectively and 5-year cumulative adenoma rates were analysed according to three risk groups: normal (no baseline adenoma), low-risk (1–2 adenomas <10 mm) and high-risk (an advanced adenoma or ≥3 adenomas) groups. The RR was computed by HR using Cox proportional regression after multivariate adjustments. The primary outcome was the 5-year cumulative rate of recurrent advanced adenoma in each risk category and the secondary outcome was its predictive factors. Results: Among 3803 subjects enrolled between 2003 and 2005, 2452 were followed-up within 5 years: 1242, 671 and 539 in the normal, low-risk and high-risk groups, respectively. Compared with the normal group, the low-risk group had a sufficiently low 5-year incidence and did not show an increased risk for subsequent advanced adenoma (2.4% vs 2.0%, HR=1.14, 95% CI 0.61 to 2.17). Conversely, a significantly higher 5-year rate (12.2%) and early recurrence (4.6, 7.4 and 9.6% at 1, 2 and 3 years) of advanced adenoma were revealed in the high-risk group. Among various patients and adenoma characteristics, only high-risk adenoma (HR=5.95, 95% CI 3.66 to 9.68) along with a number of ≥3 (HR=3.06, 95% CI 1.51 to 6.57) and size ≥10 mm (HR=3.02, 95% CI 1.80 to 5.06) were independent predictors. Conclusions: The surveillance interval for low-risk patients could be extended beyond 5 years. Colonoscopic surveillance should be targeted to high-risk patients, and 3-year follow-up after initial polypectomy may be appropriate.