Background: The multi-target stool DNA test (mt-sDNA) is an FDA approved, high sensitivity, colorectal cancer screening test. We evaluated mt-sDNA in non-screening-compliant Medicare patients and assessed compliance and diagnostic colonoscopy usage and correlated positive mt-sDNA results with colonoscopy findings.

Methods: We performed a retrospective medical records review (October 2014 - September 2015) to identify mt-sDNA use in average-risk Medicare eligible patients treated by USMD Physician Services (Dallas, Tx) who were not previously compliant with colon cancer screening. We offered mt-sDNA to patients who were either >10 years since last colonoscopy and/or >1 yr. since last fecal occult blood test. Follow-up colonoscopy was advised for all patients with a positive result. Colonoscopy and pathology results were reviewed with patient classification based on the most significant pathology finding (index lesion). Size, location and total number of polyps and adenomas were tabulated.

Results: Over 12 months, 77 providers ordered 393 mt-sDNA studies with 347 completed (88.3% compliance). Patient mean age was 69.8 (50-85) and patients were 64% female. Mt-sDNA was negative in 85.3% (296/347) and positive in 14.7% (51/347). Follow-up colonoscopy was performed in 46 positive patients (90.2% colonoscopy compliance) with 3 patients refusing colonoscopy and two patients lost to follow up. Index findings included: colon cancer (4/46, 8.7%), advanced adenomas (21/46, 45.6%), non-advanced adenoma (9/46, 19.6%), and negative results (12/46,23.0%). The positive predictive value for advanced colorectal lesions was 54.3% and for any colorectal neoplasia was 73.9%.

Conclusions: The availability of mt-sDNA provided significant medical benefit to our previously screening non-compliant Medicare population. Patients with clinically critical advanced colorectal neoplasia were identified in this cohort due to high compliance with both mt-sDNA screening and follow-up diagnostic colonoscopy.

Citation Format: Mark Prince, Lynn Lester, Rupal Chinawala, Barry M. Berger. Multi-target sDNA increases colorectal cancer screening among previously non-compliant patients: The USMD physician services experience. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr LB-296.