Retrospective Study
Copyright ©The Author(s) 2022. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Aug 14, 2022; 28(30): 4152-4162
Published online Aug 14, 2022. doi: 10.3748/wjg.v28.i30.4152
Cumulative incidence and risk factors for pouch adenomas associated with familial adenomatous polyposis following restorative proctocolectomy
Hyo Seon Ryu, Chang Sik Yu, Young Il Kim, Jong Lyul Lee, Chan Wook Kim, Yong Sik Yoon, In Ja Park, Seok-Byung Lim, Jin Cheon Kim
Hyo Seon Ryu, Chang Sik Yu, Young Il Kim, Jong Lyul Lee, Chan Wook Kim, Yong Sik Yoon, In Ja Park, Seok-Byung Lim, Jin Cheon Kim, Division of Colon and Rectal Surgery, Department of Surgery, University of Ulsan College of Medicine, Asan Medical Center, Seoul 05505, South Korea
Author contributions: Ryu HS designed and performed the research and wrote the paper; Yu CS designed the research and supervised the report; Kim YI, Lee JL, Kim CW, Yoon YS, Park IJ, Lim SB, and Kim JC provided clinical advice and supervised the report.
Institutional review board statement: The protocol for this research project has been approved by a suitably constituted ethics committee of the institution (Committee of Asan Medical Center, Approval No. 2021-0309), and it conforms to the provisions of the Declaration of Helsinki.
Informed consent statement: Patients were not required to give informed consent to the study because the analysis used anonymous clinical data that were obtained after each patient agreed to treatment by written consent.
Conflict-of-interest statement: This study did not receive a specific grant from any funding agency in the public, commercial, or not-for-profit sectors.
Data sharing statement: No additional data are available.
Open-Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: https://creativecommons.org/Licenses/by-nc/4.0/
Corresponding author: Chang Sik Yu, MD, PhD, Professor, Division of Colon and Rectal Surgery, Department of Surgery, University of Ulsan College of Medicine, Asan Medical Center, 88 Olympic-ro 43-gil, Songpa-gu, Seoul 05505, South Korea. csyu@amc.seoul.kr
Received: March 3, 2022
Peer-review started: March 3, 2022
First decision: April 11, 2022
Revised: April 24, 2022
Accepted: July 18, 2022
Article in press: July 18, 2022
Published online: August 14, 2022
Processing time: 159 Days and 19.7 Hours
Abstract
BACKGROUND

The emergence of restorative total proctocolectomy has significantly reduced the lifetime colorectal cancer risk associated with familial adenomatous polyposis (FAP). However, adenomas may develop in the ileal pouch over time and may even progress to carcinoma. We evaluated the cumulative incidence, time to development, and risk factors associated with ileal pouch adenoma.

AIM

To evaluate the cumulative incidence, time to development, and risk factors associated with pouch adenoma.

METHODS

In this retrospective, observational study conducted at a tertiary center, 95 patients with FAP who underwent restorative proctocolectomy at our center between 1989 and 2018 were consecutively included. The mean follow-up period was 88 mo.

RESULTS

Pouch adenomas were found in 24 (25.3%) patients, with a median time of 52 mo to their first formation. Tubular adenomas were detected in most patients (95.9%). There were no high-grade dysplasia or malignancies. Of the 24 patients with pouch adenomas, 13 had all detected adenomas removed. Among the 13 patients who underwent complete adenoma removal, four (38.5%) developed recurrence. Among 11 (45.8%) patients with numerous polyps within the pouch, seven (63.6%) exhibited progression of pouch adenoma. The cumulative risks of pouch adenoma development at 5, 10, and 15 years after pouch surgery were 15.2%, 29.6%, and 44.1%, respectively. Severe colorectal polyposis (with more than 1000 polyps) was a significant risk factor for pouch adenoma development (hazard ratio, 2.49; 95% confidence interval: 1.04-5.96; P = 0.041).

CONCLUSION

Pouch adenomas occur at a fairly high rate in association with FAP after restorative proctocolectomy, and a high colorectal polyp count is associated with pouch adenoma development.

Keywords: Adenomatous polyposis coli; Familial adenomatous polyposis; Adenoma; Intestinal polyps; Proctocolectomy, restorative; Ileal pouch anal anastomosis

Core Tip: This is a retrospective study that evaluated the cumulative incidence and risk factors for pouch adenoma in association with familial adenomatous polyposis following restorative proctocolectomy. The incidence of pouch adenoma was 25.3%, and the cumulative risk 15 years after pouch surgery was 44.1%. Severe colorectal polyposis was a significant risk factor for pouch adenoma development. In our series, 62% of adenomas did not recur after endoscopic removal, but 63% of patients under observation showed progression. There was no spontaneous adenoma diminution or disappearance. Close endoscopic pouch surveillance is essential, and new pouch adenoma management guidelines are needed.