Follow-up Colorectal Cancer Screening After Negative-Result and Positive-Result Multitarget Stool DNA Tests: A Population-Based Study in Southeast Minnesota

Objective

To provide contemporary data on subsequent screening after negative-result multitarget stool DNA (mt-sDNA) tests and follow-up colonoscopy after positive-result mt-sDNA tests.

Patients and Methods

Negative-result mt-sDNA tests (for patients aged 50-72 years) and positive-result mt-sDNA tests (for patients aged 50-75 years) were identified among average risk patients from a 9-county region in Southeast Minnesota from January 1, 2016 to December 31, 2022. Competing risks models of time to subsequent colorectal cancer (CRC) screening were modeled separately for the negative mt-sDNA and positive mt-sDNA cohorts. Multistate Cox proportional hazards models compared rates of CRC screening modality by patient demographic characteristics.

Results

At 3.5 years after a negative-result mt-sDNA test (n=18,739 tests), 55.0% (95% CI, 53.9%-56.3%) of patients were rescreened, which increased to 81.0% (95% CI, 80.0%-82.1%) at 5 years. Most tests were repeat mt-sDNA tests (48.3% at 3.5 years; 95% CI, 47.2%-49.5%). Rescreening with any modality was more likely with older age and among females and less likely among Black persons, Asian persons, and those with other or mixed race. After a positive-result mt-sDNA test (n=2863 tests), 80.9% (95% CI, 79.6%-82.6%) and 84.4% (95% CI, 83.2%-86.0%) of patients completed follow-up colonoscopy by 6 months and 1 year, respectively. Those of other or mixed race had lower rates of follow-up colonoscopy compared with White persons.

Conclusion

Although rates of overall rescreening after a negative-result mt-sDNA test and follow-up colonoscopy after positive-result mt-sDNA tests were high, racial disparities were apparent. Targeted interventions are needed to improve equity in CRC screening adherence and follow-up care across diverse patient populations.