S287 Comparison of Cost-Effectiveness Outcomes Between a Novel Multitargeted Stool-Based RNA Test and Alternative Non-Invasive Stool and Blood Tests for Colorectal Cancer Screening

Abstract

Introduction: Colorectal cancer (CRC) mortality has been significantly mitigated by increased CRC screening via colonoscopy. Colonoscopy has low compliance rates due to invasiveness, procedure-associated risks, bowel preparation, and time requirements. Existing non-invasive screening methods are limited by relatively low sensitivity for precancerous lesions, especially advanced adenomas (AAs). Using a Markov model, cost-effectiveness outcomes were compared between a novel multitargeted stool RNA (mt-sRNA) test, existing stool-based screening tests (fecal immunochemical test [FIT], and multitarget stool DNA [mt-sDNA]), no screening, and a recently introduced triennial blood-based screening test. Methods: The Markov model compared morbidity, mortality, and cost using 1,000 average-risk patients 45-75 years of age over a 30-year time horizon. The model input included test-specific sensitivity and specificity with a fixed incidence and prevalence of CRCs/AAs to assess lesion detection rates across each screening method. Reimbursement rates were assumed equal for blood, mt-sDNA, and mt-sRNA tests ($508). Data on distribution across disease stages and five-year survival rates predicted long-term outcomes for patients with CRC. The model accounts for the cost of screening, complications associated with colonoscopy, surveillance/follow-up requirements, and the cost of CRC treatment. For the primary analysis, adherence was assumed to be 100%. For secondary research, adherence was set at 40%, 60%, and 80%. Results: At 100% adherence, the mt-sRNA test resulted in an additional reduction in CRC cases by 68.1% (blood test), 42.5% (mt-sDNA test), 30.8% (FIT test), and 82.1% (no screening). The mt-sRNA screening strategy also resulted in the reduction of deaths by 64.7% (blood test), 39.8% (mt-sDNA test), 29.8% (FIT test), and 78.3% (no screening). When adherence is set at 40%, 60%, or 80%, use of the mt-sRNA test results in an increased number of pre-cancerous adenomas detected relative to all other screening strategies. Incremental costs associated with the mt-sRNA test were intermediary with higher costs associated with follow-on colonoscopy/surveillance, and lower costs associated with CRC treatment. Conclusion: This model suggests that CRC screening tests that target advanced adenomas detection have superior cost-effectiveness due to better cancer prevention. The mt-sRNA test is a more cost-effective alternative for colorectal cancer screening in the average-risk population than other non-invasive strategies (Table). Table 1. - Cost-effectiveness of mt-sRNA against other screening modalities at variable adherence rates, per 1000 patients over a 30-year time horizon Adherence rate mt-sRNA test vs. Incremental CRC cases prevented CRC cases reduction (%) CRC deaths reduction (%) Incremental costs per CRC case prevented Incremental costs per CRC case prevented 40% for all tests Blood test 14 39.5% 35.1% -$175,379 -$311,289 mt-sDNA 6 22.7% 19.9% -$168,747 -$302,667 FIT 6 21.2% 19.0% $8,666 $14,681 No screening 20 48.1% 42.8% $67,232 $122,252 60% for all tests Blood test 16 51.5% 47.0% -$182,381 -$309,202 mt-sDNA 7 30.8% 27.7% -$178,940 -$293,907 FIT 5 23.0% 21.2% $188,435 $296,188 No screening 27 63.6% 58.3% $29,789 $52,683 80% for all tests Blood test 17 60.3% 56.2% -$188,028 -$306,278 mt-sDNA 7 37.2% 34.2% -$182,141 -$284,899 FIT 4 26.1% 24.6% $409,606 $607,669 No screening 31 73.9% 69.2% $19,817 $34,312 100% for all tests Blood test 16 68.1% 64.7% -$3,104,328 -$103,478 mt-sDNA 6 42.5% 39.8% -$1,073,985 -$35,799 FIT 3 30.8% 29.8% $2,289,314 $76,310 No screening 35 82.1% 78.3% $612,243 $20,408