Cost-effectiveness of SelectMDx for Prostate Cancer in Four European Countries: A modelling study
The low specificity of PSA results in a considerable number of unnecessary prostate biopsies in current practice. The urinary biomarker-based test (SelectMDx) is based on a biomarker expression profile (HOXC6 and DLX1) combined with traditional risk factors. The outcome is a risk score to detect high-grade prostate cancer (Gleason score (GS) >= 7) upon biopsy. As the negative predictive value (NPV) of this test is 98% for high-grade prostate cancer (PCa), the test is used to reduce the number of unnecessary prostate biopsies. Furthermore, overdiagnosis and overtreatment of insignificant PCas can be lowered. Besides the diagnostic accuracy of the test, the context of its use also determines its cost-effectiveness. This context can differ between countries. Therefore, the potential health benefit and cost-effectiveness of the test was assessed in France, Italy, The Netherlands and Germany.
The current standard of care (SOC) in which patients undergo transrectal ultrasound (TRUS)-guided biopsies in case of an elevated PSA was compared to a strategy in which the SelectMDx test was used to determine which patients needed to undergo prostate biopsies. We used a decision tree to represent the diagnostic and treatment pathway, followed by a Markov model to simulate the long term consequences on costs and effects. Per country, the current detection rate of significant and insignificant PCa, the management strategy and the costs of diagnostics and treatments were used as input for the model. The accuracy of the SelectMDx test, patients quality of life after the different diagnostic or treatment modalities, and the influence of missed PCas on the survival, were assumed to be identical among the countries. The main measure of effect was Quality Adjusted Life Year (QALY). Costs and QALYs were calculated over 18 years for both strategies.
In all four countries, the negative consequences of missed significant PCas in the SelectMDx strategy were outweighed by the prevention of negative effects associated with biopsies in this strategy. Most important was the prevention of overdiagnosis and overtreatment of insignificant PCa. In France, the new strategy resulted in 0.020 QALYs gained and a cost saving of 1,217 Euro per patient compared to the SOC. In Italy the expected QALY gain and cost savings were 0.028 and 762 Euro, while in the Netherlands this was 0.01 and 129 Euro, respectively. For the German situation the model showed a QALY gain of 0.014 and a cost saving of 442 Euro.
The results of the Markov model showed that using SelectMDx in addition to serum PSA in the diagnostic pathway, QALY could be gained while saving healthcare costs. Despite some differences between the countries the significant presence of overtreatment and overdiagnosis in the current SOC was the main factor that resulted in the beneficial outcomes using SelectMDx for risk stratification.
Funding: This study was funded by MDxHealth