Cost-effectiveness of genotype-guided aspirin use for colorectal cancer prevention.

Abstract

e18318 Background: Colonoscopy is the “gold standard” for colorectal cancer (CRC) screening. However, adherence rates are low and detection is not optimal. Concomitant aspirin chemoprevention is recommended by US Preventive Task Force, but bleeding complications can be limiting. Variant genotypes in aspirin metabolism can modify CRC and adenoma risk. Genotype guided aspirin (ggASA) use will identify a targeted average-risk population for maximal aspirin benefit while minimizing adverse events rates compared to the general population. We conducted a cost-effectiveness analysis (CEA) of primary chemoprevention in CRC using ggASA compared to no intervention, and colonoscopy ±general aspirin in healthy average-risk individuals. Methods: Our Markov decision analytical model consisted of 5 possible health states: no CRC/polyps, adenoma, pre-clinical CRC, CRC, and death. Model probabilities for CRC and its prevalence were estimated using SEER database and published literature. A microsimulation of 10,000 individuals aged 50-64 years was used to estimate cost-effectiveness from US payer perspective over lifetime. One way and probabilistic sensitivity analyses and model validation results will be reported in the final poster. Results: Our results suggest that compared to colonoscopy and no intervention, ggASA was associated with fewer CRC cases, and CRC-related deaths and MI cases. Compared to colonoscopy + general aspirin, ggASA was associated with fewer bleeding events, similar rates of CRC and CRC-related deaths, and fewer MI cases prevented. From a cost-effectiveness standpoint, ggASA use over a lifetime had the lowest costs and highest quality adjusted life years gained compared to other strategies, if testing costs were ignored. Once genetic testing costs exceeds $63, colonoscopy + general aspirin becomes the most cost effective strategy. Between genetic testing cost of $63-283, the costs of using ggASA per quality adjusted life year gained is below $100,000. Conclusions: Genotype-guided aspirin use precisely identifies an average-risk population, and lowers adverse events rates compared to general aspirin. The economic value of genotype-guided aspirin is dependent on the genetic testing costs.