An Exploratory Analysis of the Cost-Effectiveness of a Multi-cancer Early Detection Blood Test Compared with Standard of Care Screening in Ontario, Canada.

Abstract

Determining whether multi-cancer early detection (MCED) tests are cost effective is important in deciding whether they should be included in the clinical path of cancer care, especially for cancers where screening tools do not exist. 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. Cost effectiveness was estimated from a provincial Ministry of Health perspective. 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 published by the Canadian Agency for Drugs and Technologies in Health (CADTH) for conducting a cost-effectiveness analysis, which included a discount rate of 1.5% applied to all costs and outcomes. Costs were also converted to 2022 Canadian dollars. To test the robustness of the model, both univariate and probabilistic sensitivity analyses were conducted. MCED screening resulted 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 with standard of care. 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 probabilistic sensitivity analyses revealed that the MCED intervention strategy was preferred to standard of care no more than 2% of the time at this WTP for both males and females. The model was most sensitive to the cost of MCED screening, and the levels of specificity of the MCED and colorectal cancer screening tests. 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.