Dr Jill Tinmouth and colleagues conducted a systematic review and meta-analysis of the risk of advanced adenomas, colorectal cancer, and/or colorectal cancer-related death among individuals with low-risk adenomas.
The team searched PubMed and Embase for studies published between 2006 and 2015.
Quality and strength of the evidence were rated using the Newcastle-Ottawa Scale (NOS) and the GRADE framework, respectively.
The researchers identified 11 observational studies.
A meta-analysis of 8 cohort studies showed a small but statistically significant increase in the incidence of advanced adenomas in individuals with LRAs compared with those with a normal baseline colonoscopy.
|There was a 25% reduction in colorectal cancer mortality in individuals with low-risk adenomas |
|American Journal of Gastroenterology|
The research team noted that the pooled 5-year cumulative incidence of advanced adenomas was 3%, 5%, and 17% for the no adenoma, low-risk adenomas, and advanced adenoma baseline groups, respectively.
The team found that 2 studies, which could not be pooled, showed a reduction in the risk of colorectal cancer in individuals with low-risk adenomas compared with the general population at a median follow-up of 8 years and odds ratio of 0.4.
The researchers observed that 1 large retrospective cohort study found a 25% reduction in colorectal cancer mortality in individuals with low-risk adenomas compared with the general population.
Dr Tinmouth's team concludes, "We observed a small but significant increase in the risk of advanced adenomas in people with low-risk adenomas compared with those with a normal baseline colonoscopy, but compared with the general population, people with LRAs have significantly lower risks of colorectal cancer and of colorectal cancer-related mortality."