Global Prevalence of Colorectal Neoplasia: A Systematic Review and Meta-Analysis

Abstract

BACKGROUND & AIMS:Most colorectal cancers (CRC) arise from colorectal adenomas, yet there is not enough information on global prevalence to inform health care policy. We examined the prevalence of any type of adenomas, advanced adenomas (AADs), and CRC according to age, sex, ethnicity, geographic regions, and anatomic location (proximal vs distal). METHODS:MEDLINE and Embase were searched from their inception through May 1, 2018, to identify population-based, observational studies that reported the prevalence of colorectal neoplasia. Studies on participants 15 years or older, with a sample size of 500 persons or more, were included. Metaprop (College Station, TX) was used to model within-study variability by binomial distribution and Freeman-Tukey Double Arcsine Transformation to stabilize the variances. The prevalence figures were presented by proportions and their 95% CIs using random-effects models. RESULTS:Our meta-analysis included 70 studies involving 637,414 individuals. The overall prevalence rates of adenoma (23.9%; 95% CI, 22.2%-25.8%), AAD (4.6%; 95% CI, 3.8%-5.5%), and CRC (0.4%, 95% CI, 0.3%-0.5%) were calculated. Subgroup analysis indicated that prevalence values (adenomas, AADs, and CRCs) were higher among men (29.7%, 6.5%, and 0.8%, respectively) than women (19.3%, 3.8% and 0.4%, respectively), among older adults (25.9%, 5.2%, and 0.6%, respectively) than younger adults (14.6%, 1.6%, and 0.1%, respectively), among Caucasians (23.7%, 6.6%, and 0.5%, respectively) than other ethnicities, in European countries (25.9%, 8.4%, and 0.8%, respectively) than other countries, and among patients with proximal (25.9%, 5.3%, and 0.1%, respectively) vs distal neoplasia. CONCLUSIONS:In a systematic review and meta-analysis, we found a high prevalence of colorectal neoplasia among some populations. This indicates a need to expand CRC screening programs for these groups. The pooled prevalence estimates can be used as quality indicators for established CRC screening programs.

AGA Clinical Practice Guidelines on the Gastrointestinal Evaluation of Iron Deficiency Anemia

“…As a comparison, a recent meta-analysis found a prevalence of colorectal cancer of 0.8% (95% CI, 0.4%-0.7%) in individuals age 50 years and older. 8 High-quality evidence from randomized controlled trials of flexible sigmoidoscopy 9,10 showed that endoscopic screening reduces colorectal cancer incidence and mortality. Indirectly, this suggests that detection of colorectal cancer through endoscopic evaluation of patients with IDA is important, particularly with the ongoing advances in therapy for colorectal cancer and subsequent improvements in survival.…”

“…As a comparison, a recent meta-analysis found a prevalence of colorectal cancer of 0.1% (95% CI, 0%-0.1%) in individuals younger than 50 years, but did not estimate incidence separately for men and women. 8 It should also be noted that the incidence of colorectal cancer has increased in younger cohorts recently. 17 We did not find reliable data to define the risk of gastrointestinal malignancy in premenopausal women at different ages or with different degrees of anemia, but the prevalence of either upper or lower gastrointestinal malignancy will decrease with decreasing age in this population.…”

Variation in changes in the incidence of colorectal cancer by age and association with screening uptake: an observational study

“…However, this is highly unlikely, given that the fall in incidence seen in the flexible sigmoidoscopy screening trials was accompanied by reductions in mortality. 7 In addition, just as North America, Oceania and most European countries, 6 CRC mortality in the 50-74 years age range in Scotland has fallen over time and it is likely that part of this effect can be attributed to early detection and prevention of disease as a result of screening. 16 It is also interesting that we did not observe a fall in CRC mortality in the under 50 years age range, lending further strength to the argument that screening has contributed to this trend.…”

“…3 In a recent analysis of incidence and mortality databases from 39 countries, it was confirmed that countries with the highest HDI had a decrease in CRC incidence, but that incidence of colon and rectal cancers has continued to increase in countries with medium-high HDI, and in younger populations. 6 It has been postulated that screening may be responsible for the reduction in incidence in the group aged over 50 years, especially where this is associated with high rates of large bowel endoscopy, which facilitates the diagnosis and removal of pre-malignant adenomas. 3 Since there is now robust evidence from randomised trials of endoscopic screening that removal of adenoma leads to a reduction in CRC incidence, 7 this is an attractive hypothesis, but one that is difficult to test.…”

Classifying colorectal cancer or colorectal polyps in endoscopic setting using convolutional neural network: protocol for a systematic review and meta-analysis

“…A new systematic review and meta-analysis combined 70 primary population-based cross-sectional studies that used colonoscopy for assessing different colorectal neoplastic lesions. This study reported the worldwide prevalence of adenoma, advanced adenoma and CRC as 25.9%, 5.2% and 0.6% in patients older than 50 years, respectively 3 . Brenner et al investigated almost 850,000 colonoscopies of German national screening of CRC.…”