A StFX interdisciplinary health professor has just published a research paper in a leading journal aimed at estimating the duration that patients remain at reduced risk of colorectal cancer incidence and mortality after a complete colonoscopy.
Dr. Arlinda Ruco, who is first author on the paper with colleagues from the University of Melbourne, the University of Toronto, the University of Ottawa and ICES, explored the association between receipt of colonoscopy and colorectal cancer incidence and mortality. The paper titled “Duration of risk reduction in colorectal cancer incidence and mortality after a complete colonoscopy in Ontario, Canada: a population-based cohort study” was recently published in The Lancet Gastroenterology & Hepatology, one of the top journals in the field.
“This was a very large retrospective cohort study of over 5.2 million individuals that showed that those that have a complete colonoscopy with no findings remain at a lower risk for colorectal cancer incidence and mortality for more than 15 years after the procedure. The current screening guidelines typically recommend re-screening after 10 years. Our findings therefore suggest that this recommendation be reassessed,” says Dr. Ruco.
The study included over 69 million person-years of follow-up and the authors developed a 9-level time-varying measure of exposure to capture the time since most recent complete colonoscopy and whether any intervention had occurred during that procedure.
Their findings showed that compared with those who did not have a colonoscopy, the risk of colorectal cancer in those who had a complete negative colonoscopy was reduced at all timepoints, including when the procedure occurred more than 15 years earlier. A similar finding was observed for colorectal cancer mortality, with lower risk at all timepoints, including when the procedure occurred more than 15 years earlier.
The implications of these findings are multi-fold, Dr. Ruca says. If risk reduction persists past 10 years, the recommended screening interval could be extended, reducing the burden on the individual and health-care system.
