A study published in The Lancet Oncology examined surveillance colonoscopy's effect on colorectal cancer risk.
Wendy Atkin, PhD, of London-based Imperial College, and colleagues conducted a retrospective, multicenter, cohort study using lower gastrointestinal endoscopy and pathology data from patients who were diagnosed with intermediate-risk adenomas at 17 United Kingdom-based hospitals.
Researchers identified 253,798 patients who underwent colonic endoscopy 11,944 were had intermediate-risk adenomas.
Here's what they found.
1. After a median follow-up of seven to nine years, physicians diagnosed 210 colorectal cancer cases.
2. Forty-two percent or 5,019 patients did not attend surveillance. Fifty-eight percent or 6,925 patients did attend one or more surveillance visits.
3. One or two surveillance visits significantly reduced colorectal cancer incidence rates.
4. Without surveillance, colorectal cancer incidence rates in patients with suboptimal quality colonoscopy, proximal polyps or large adenomas was higher than the general population.
5. Patients without the aforementioned features had lower colorectal cancer incidence rates than the general population.
Researchers concluded, "Colonoscopy surveillance benefits most patients with intermediate-risk adenomas. However, some patients are already at low risk after baseline colonoscopy and the value of surveillance for them is unclear."