An exploratory analysis of the cost-effectiveness of a multi-cancer early detection blood test in Ontario, Canada

Abstract

Background: Cancer is one of the main causes of death globally and early detection of tumors through screening is key to preventing morbidity and mortality. However, screening tools only exist for a few types of cancers, and so, many cancers go undetected until symptoms appear. New multi-cancer early detection (MCED) screening tools are currently being developed and have the potential to be cost-effective.

Research Objective: The main objective of this study is to determine the cost-effectiveness of including a MCED screening regimen together with existing provincial screening protocols for selected cancers that are prevalent in Ontario, Canada, among average risk persons aged 50 – 75 years. The selected cancers include breast, colorectal, lung, esophageal, liver, pancreatic, stomach and ovarian. The proposed intervention strategy was compared to current standard of care screening strategies for these selected types of cancers.

Methods: Cost-effectiveness was estimated using a cost-utility analysis from a provincial Ministry of Health perspective. To conduct this analysis, a state-transition Markov model representing the decision path of both the proposed and existing screening strategies along the natural history of the selected types of cancers was implemented. The incremental cost-effectiveness ratio (ICER) was calculated using data from available literature and the guidelines forwarded by the Canadian Agency for Drugs and Technologies in Health (CADTH) for conducting a cost-utility analysis, which included a discount rate of 1.5%. To test the robustness of the model, both univariate and probabilistic sensitivity analyses were conducted to determine the importance of selected input parameters.

Results: The analysis demonstrated that the adoption of MCED screening results in more diagnosed cases of each type of cancer, even at an earlier stage of disease. This was also associated with fewer related deaths compared to the standard of care option. Notwithstanding, the analysis revealed that the MCED intervention was not cost-effective (ICER: CAD$143,369 per Quality-adjusted life year (QALY)), given a willingness to pay (WTP) threshold of $100,000 per QALY. The model was most sensitive to the cost of screening and the level of specificity of the MCED and colorectal cancer screening tests. Notwithstanding, the probabilistic sensitivity analyses revealed that the MCED intervention strategy was at least 63% preferred to standard of care screening at the willingness to pay of $150,000 per QALY for both males and females.

Contribution: The main contribution of the study is to present and execute a methodological approach that can be adopted to test the cost-effectiveness of an MCED tool in the Canadian setting. The model is also sufficiently generic that it could be adapted to other jurisdictions, and with consideration for increasing the WTP threshold beyond the common $100,000 per QALY limit, given the life-threatening nature of cancer, to ensure that MCED interventions are cost-effective.