Prevalence of colorectal neoplasia in an average-risk Chinese population: a systematic review and meta-analysis

Abstract

BackgroundColorectal cancer is the third most commonly diagnosed cancer and the second leading cause of cancer mortality globally. Colorectal adenomas are recognised as precursors in most new cases of colorectal cancer. However, few studies reported the prevalence of different types of colorectal neoplasia among the Chinese population. This systematic review and meta-analysis estimated the prevalence of any type of adenomas, advanced adenomas, and colorectal cancer according to age and gender among average-risk Chinese populations. MethodsWe did a PRISMA-compliant search in MEDLINE, Embase, CNKI, and Wanfang Database to identify studies reporting the prevalence of colorectal neoplasia among asymptomatic Chinese individuals receiving direct colonoscopy for colorectal cancer screening, from database inception until May 29, 2019, including studies published in English and Chinese. Metaprop was used to model within-study variability by binomial distribution and Freeman-Tukey Double Arcsine Transformation to stabilise the variances in the meta-analysis. Heterogeneity was measure by I2 statistic. The prevalence data were presented by proportions and their 95% CIs using random-effects models. FindingsThis meta-analysis included 16 studies reporting on a total of 81 262 people between 1996 and 2015. The overall prevalence of adenomas was 8699 people (21·1% [95% CI 17·3–25·1]), 1855 people (4·0% [3·1–5·1]) for advanced adenomas, and 210 (0·4% [0·2–0·6]) for colorectal cancer. Subgroup analysis indicated prevalence of adenomas, advanced adenomas, and colorectal cancer was higher among men (25·0%, 4·3%, and 0·1%, respectively) than women (15·5% [p=0·14], 2·7% [p<0·0001], and <0·1% [p=0·06]). Adults aged 50 years or older had significantly higher prevalence (25·8% for adenomas; 4·9% for advanced adenomas; and 0·6% for colorectal cancer) than adults younger than 50 years (13·6% [p<0·0001], 1·1% [p<0·0001], and 0·1% [p=0·03], respectively). InterpretationThe high prevalence of colorectal neoplasia among Chinese men and older adults highlighted the need to expand colorectal cancer screening programmes for these groups. The pooled prevalence estimates can be used as quality indicators for established colorectal cancer screening programmes. Future research should investigate its time-trend prevalence that could provide important data to inform health policy making. FundingNone.