Cumulative Risk of Colorectal Cancer and Colorectal Cancer Mortality in Screen-Eligible Older Adults with History of Adequate Screening

Ronit Dalmat | 2022

Advisor: Jessica Chubak

Research Area(s): Aging & Neurodegenerative Diseases

Full Text

The decision of whether or not to continue colorectal cancer (CRC) screening at older ages is complex. Although most guidelines recommend routine screening of adults older than age 45 years for CRC, there is ambiguity on when to stop screening. The United States Preventive Services Task Force (USPSTF), American Cancer Society, and the Multi-Society Task Force all recommend screening until age 75 years, followed by individualized and shared decision-making for people 76-85 years and cessation after 85 years. However, few empirical data are available to inform older adults’ decision-making based on prior screening, particularly among persons with a prior negative test. Using a retrospective cohort of older adults in the Optimizing Colorectal Cancer Screening PREcision and Outcomes in CommunIty-baSEd Populations (PRECISE) cohort, I estimated cumulative risk of CRC incidence and mortality among two groups of screen-eligible older adults. The first had a negative colonoscopy ten years earlier; the second had a negative stool-based test one year earlier. Each group had a low risk of CRC diagnosis and of CRC mortality. Overall, cumulative CRC incidence and mortality among screen-eligible older adults occur in the context of much higher risk of death from other causes, reinforcing guidelines that recommend the benefits of ongoing screening be carefully weighed against the burdens and risks.