Retrospective Study
Copyright ©The Author(s) 2016. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. May 7, 2016; 22(17): 4380-4388
Published online May 7, 2016. doi: 10.3748/wjg.v22.i17.4380
Clinicopathological features of familial adenomatous polyposis in Korean patients
Sung Min Jung, Yong Sik Yoon, Seok-Byeong Lim, Chang Sik Yu, Jin Cheon Kim
Sung Min Jung, Yong Sik Yoon, Seok-Byeong Lim, Chang Sik Yu, Jin Cheon Kim, Division of Colon and Rectal Surgery, Department of Surgery, University of Ulsan College of Medicine, Seoul 05505, South Korea
Sung Min Jung, Yong Sik Yoon, Seok-Byeong Lim, Chang Sik Yu, Jin Cheon Kim, Asan Medical Center, Seoul 05505, South Korea
Author contributions: Jung SM designed and wrote manuscript; Kim JC designed study and provided critical comments on manuscript; Yoon YS, Lim SB and Yu CS provided clinical data and were also involved in editing the manuscript; all authors have read and approved the final version to be published.
Supported by Korea Research Foundation, Ministry of Science, ICT, No. 2013R1A2A1A03070986 (to Kim JC); Future Planning, the Korea Health 21 R&D Project, No. HI06C0868 and No. HI13C1750; and the Center for Development and Commercialization of Anti-Cancer Therapeutics, Ministry of Health and Welfare, South Korea, No. HI10C2014.
Institutional review board statement: The study was reviewed and approved by the Institutional Review Board of Asan Medical Center (No. 2015-0585).
Conflict-of-interest statement: The authors declare that they have no conflict of interest.
Data sharing statement: No additional data are available.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (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:
Correspondence to: Jin Cheon Kim, MD, PhD, Professor, Division of Colon and Rectal Surgery, Department of Surgery, University of Ulsan College of Medicine, 88 Olympic-ro 43 gil, Songpa-gu, Seoul 05505, South Korea.
Telephone: +82-2-30103489 Fax: +82-2-4749027
Received: December 6, 2015
Peer-review started: December 7, 2015
First decision: January 28, 2016
Revised: February 2, 2016
Accepted: March 2, 2016
Article in press: March 2, 2016
Published online: May 7, 2016
Processing time: 145 Days and 8 Hours

AIM: To identify prognostic factors and to correlate APC mutations with clinical features, including extracolic manifestations.

METHODS: One hundred thirty-five patients who underwent surgical procedures for familial adenomatous polyposis (FAP) were included. FAP was diagnosed when the number of adenomatous polyps was > 100. Data related to patient, extracoloic manifestations, cancer characteristics, operative procedure, follow up and surveillance were collected. APC mutation testing was performed in the 30 most recent patients. DNA was extracted from peripheral blood and polymerase chain reaction products using 31 primer pairs on APC gene were sequenced. A retrospective study was performed to investigate a causal relationship between prognosis and feature of patient.

RESULTS: The mean age of the 51 patients with colorectal cancer (CRC) was older than that of those without CRC (30.5 vs 36.9, P = 0.002). Older individuals were more likely to have colon cancer at the time of FAP diagnosis [odds ratio, 4.75 (95%CI: 1.71-13.89) and 5.91(1.76-22.12) for 40-49 years and age > 50 vs age < 30). The number of confirmed deaths was 13 and the median age at death was 40 years (range, 27 to 85 years). Ten of the deaths (76.9%) were from CRC. Another cause of two cases of death were desmoid tumors (15.4%). Development of cancer on remnant rectal or ileal mucosa after surgery was not observed. The APC mutation testing revealed 23 pathogenic mutations and one likely pathogenic mutation, among which were four novel mutations. The correlation between mutational status and clinical manifestations was investigated. Mutations that could prodict poor prognosis were at codon 1309 which located on mutation cluster region, codon 1465 and codon 1507.

CONCLUSION: Identification of APC mutations should aid in the diagnosis and counseling of family members in terms of early diagnosis and management of FAP.

Keywords: Adenomatous polyposis coli, Colorectal neoplasms, APC gene, Prognosis, Survival

Core tip: Diagnostic delay to make adequate management harder, resulting in advanced colorectal cancer and accompanying morbidities, was not uncommon in patients with familial adenomatous polyposis. This study investigated prognostic factors and the correlation between APC mutations and clinical features, including extracolic manifestations. The present study revealed that early diagnosis and management of high-risk patients is essential and suggests the necessary APC mutations testing in the diagnosis and counseling of patients by informing on disease prognosis.