Research Article The Prevalence of Colorectal Adenomas in Asymptomatic Korean Men and Women Moon Hee Yang 1 , Sanjay Rampal 4,5 , Jidong Sung 1,2 , Yoon-Ho Choi 1,2 , Hee Jung Son 1,2 , Jun Haeng Lee 2 , Young-Ho Kim 2 , Dong Kyung Chang 2 , Poong-Lyul Rhee 2 , Jong Chul Rhee 2 , Eliseo Guallar 5 , and Juhee Cho 3,5 Abstract Background: Colorectal cancer incidence is rapidly rising in many Asian countries, with rates approaching those of Western countries. This study aimed to evaluate the prevalence and trends of colorectal adenomas by age, sex, and risk strata in asymptomatic Koreans. Methods: Cross-sectional study of 19,372 consecutive participants aged 20 to 79 years undergoing screening colonoscopy at the Center for Health Promotion of the Samsung Medical Center in Korea from January 2006 to June 2009. Results: Among participants at average risk, those without a history of colorectal polyps or a family history of colorectal cancer, the prevalence of colorectal adenomas and advanced adenomas were 34.5% and 3.1%, respectively, in men and 20.0% and 1.6%, respectively, in women. The prevalence of adenomas increased with age in both men and women, with a more marked increase for advanced adenoma. Participants with a family history of colorectal cancer or with a history of colorectal polyps had significantly higher prevalence of adenomas compared with participants of average risk (36.9% vs. 26.9%; age- and sex-adjusted prevalence ratio ¼ 1.16; 95% confidence interval, 1.09–1.22). The prevalence of adenomas increased annually in both men and women. Conclusions: In this large study of asymptomatic Korean men and women participating in a colonoscopy screening program, the prevalence of colorectal adenomas was comparable and possibly higher than previously reported in Western countries. Impact: Cost-effectiveness studies investigating the optimal age for starting colonoscopy screening and etiological studies to identify the reasons for the increasing trend in colorectal adenomas in Koreans are needed. Cancer Epidemiol Biomarkers Prev; 23(3); 499–507. Ó2014 AACR. Introduction Colorectal cancer incidence is rapidly rising in many Asian countries, with rates approaching those of Western countries (1). In Korea, the age-standardized incidence rate of colorectal cancer has increased from 20.4 to 36.2 per 100,000 between 1999 and 2009, with a higher increase in men (from 26.2 to 49.0 per 100,000 population) compared with women (16.4 to 25.9 per 100,000 population; ref. 2). The increasing incidence of colorectal cancer in recent years among Asian countries has been attributed to die- tary changes, and higher prevalence of smoking, alcohol consumption, and sedentary lifestyle (3, 4). Indeed, in 2012 colorectal cancer accounted for 13.7% of new cancer cases and 11.2% of cancer deaths in Korea (5), highlighting the need for better colorectal cancer prevention and screening. Between 1998 and 2004, the average prevalence of colorectal adenomas and advanced adenomas were esti- mated at 30.2% and 4.1%, respectively, among average- risk Koreans older than 50 (6). These participants had no symptoms of colorectal disease, no personal history of colorectal cancer, polyps, or inflammatory bowel disease, no colon examination within the last 10 years, no pre- vious colonic surgery, and no family history of colorec- tal polyps. Similarly, a multicenter colonoscopy survey conducted in 2003 to 2004 among 11 university hospitals in Korea found prevalence rates of 33.3% and 2.2% for colorectal adenomas and advanced adenomas, respec- tively (7). Although it is assumed that the incidence of colorectal adenomas is increasing in proportion to colo- rectal cancer rates, there is limited data on recent ade- noma trends in Korea (8). Our study aimed to evaluate the prevalence and trends of colorectal adenomas by age, sex, and risk strata in asymptomatic Korean men Authors' Affiliations: 1 Center for Health Promotion, Samsung Medical Center; 2 Department of Internal Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine; and 3 Department of Health Sciences and Technology, SAIHST, Sungkyunkwan University, Seoul, Korea; 4 Department of Social and Preventive Medicine, Julius Centre University of Malaya, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia; and 5 Department of Epidemiology and Welch Center for Prevention, Epidemiology, and Clinical Research, Johns Hopkins Univer- sity Bloomberg School of Public Health, Baltimore, Maryland M.H. Yang and S. Rampal contributed equally as first authors to this work. Corresponding Author: Juhee Cho, Department of Health Sciences and Technology, SAIHST, Sungkyunkwan University, 50, Irwon-Dong Kang- nam-Gu, Seoul 135-710, Korea. Phone: 82-2-3410-1448; Fax: 82-2-3410- 6639; E mail: jcho@skku.edu doi: 10.1158/1055-9965.EPI-13-0682 Ó2014 American Association for Cancer Research. Cancer Epidemiology, Biomarkers & Prevention www.aacrjournals.org 499 Downloaded from http://aacrjournals.org/cebp/article-pdf/23/3/499/2278486/499.pdf by guest on 26 January 2023