Colonic adenomas: prevalence and incidence rates, growth rates, and miss rates at colonoscopy

Cost-effective use of colonic imaging studies can be achieved through an understanding of the prevalence, incidence, growth, and miss rates of colon adenomas. High adenoma prevalence rates are associated with increasing age, male gender, and a family history of colorectal cancer or multiple first-degree relatives with colorectal neoplasia or neoplasia diagnosed at a young age. The incidence rate of advanced adenomas is higher in patients with multiple adenomas and is likely also associated with a family history of colorectal cancer, increased age, and large adenoma size at the index examination. Direct observational data on growth rates suggests that adenomas <1 cm in size have a fairly stable size over a 3-year interval. Although colonoscopy is the most sensitive colonic imaging study, substantial miss rates for small adenomas are inherent to the procedure. Advancements in endoscopic technology should lead to reduced miss rates, allowing expansion of intervals between examinations while reducing negative outcomes of fatal interval cancers.