Randomised comparison of postpolypectomy surveillance intervals following a two-round baseline colonoscopy: the Japan Polyp Study Workgroup. Issue 8 (2nd November 2020)

• Record Type: Journal Article
• Authors: Matsuda, Takahisa; Fujii, Takahiro; Sano, Yasushi; Kudo, Shin-ei; Oda, Yasushi; Hotta, Kinichi; Shimoda, Tadakazu; Saito, Yutaka; Kobayashi, Nozomu; Sekiguchi, Masau; Konishi, Kazuo; Ikematsu, Hiroaki; Iishi, Hiroyasu; Takeuchi, Yoji; Igarashi, Masahiro; Kobayashi, Kiyonori; Sada, Miwa; Yamaguchi, Yuichiro; Hasuda, Kiwamu; Shinohara, Tomoaki; Ishikawa, Hideki; Murakami, Yoshitaka; Taniguchi, Hirokazu; Fujimori, Takahiro; Ajioka, Yoichi; Yoshida, Shigeaki
• Is Part Of: Gut. Volume 70:Issue 8(2021)
• Page Start: 1469
• Page End: 1478
• Publication Date: 2020-11-02
• Subjects: colonoscopy -- endoscopic polypectomy -- surveillance -- colorectal cancer -- colorectal adenomas; Gastroenterology -- Periodicals; 616.33
• DOI: 10.1136/gutjnl-2020-321996
• Languages: English
• ISSNs: 0017-5749

Abstract

Abstract : Objective: To assess whether follow-up colonoscopy after polypectomy at 3 years only, or at 1 and 3 years would effectively detect advanced neoplasia (AN), including nonpolypoid colorectal neoplasms (NP-CRNs). Design: A prospective multicentre randomised controlled trial was conducted in 11 Japanese institutions. The enrolled participants underwent a two-round baseline colonoscopy (interval: 1 year) to remove all neoplastic lesions. Subsequently, they were randomly assigned to undergo follow-up colonoscopy at 1 and 3 years (2-examination group) or at 3 years only (1-examination group). The incidence of AN, defined as lesions with low-grade dysplasia ≥10 mm, high-grade dysplasia or invasive cancer, at follow-up colonoscopy was evaluated. Results: A total of 3926 patients were enrolled in this study. The mean age was 57.3 (range: 40–69) years, and 2440 (62%) were male. Of these, 2166 patients were assigned to two groups (2-examination: 1087, 1-examination: 1079). Overall, we detected 29 AN in 28 patients at follow-up colonoscopy in both groups. On per-protocol analysis (701 in 2-examination vs 763 in 1-examination group), the incidence of AN was similar between the two groups (1.7% vs 2.1%, p=0.599). The results of the non-inferiority test were significant (p=0.017 in per-protocol, p=0.001 in intention-to-treat analysis). NP-CRNs composed of dominantly of the detected AN (62%, 18/29), and most of them were classified into laterally spreading tumour non-granular type (83%, 15/18). Conclusion: After a two-round baseline colonoscopy, follow-up colonoscopy at 3 years detected AN, including NP-CRNs, as effectively as follow-up colonoscopies performed after 1 and 3 years.