Cost-effectiveness of a two-gene urine biomarker assay in MRI strategies for the initial detection of prostate cancer.

Abstract

91 Background: MRI is increasingly used in men with a suspicion for prostate cancer (PCa) to target abnormal areas next to systematic biopsy. Although, MRI increases the detection of clinically significant PCa compared to systematic biopsy alone, overdiagnosis and overtreatment of insignificant disease still exists. The 2-gene mRNA PCR urine test combined with traditional risk factors SelectMDx (MDxhealth Irvine Ca) predicts clinically significant PCa, and can be used to reduce overdiagnosis and overtreatment. We assessed the cost-effectiveness of SelectMDx in a population of U.S. men who in the current situation undergo initial MRI and biopsies. Methods: We developed a decision-analytic model to simulate the downstream outcomes in the current MRI strategy, i.e. systematic biopsy plus targeted biopsy in case of a positive MRI. SelectMDx was assessed in two different diagnostic pathways: 1) before MRI to select patients for MRI and biopsy, 2) after a negative MRI to select patients for systematic biopsy. Outcomes were quality-adjusted life years (QALYs) and costs. Model parameters were informed by literature. Two scenarios regarding the mortality of missed PCa were used, using SPCG trial data and using data from the PIVOT trial. Results: Using SelectMDx before MRI (1) resulted in a health gain of 0.003 and 0.030 QALY per patient compared to the current MRI strategy, using the SPCG and PIVOT data, respectively. Cost savings were $1590 per patient and about $496 million for the yearly population of men at risk in the U.S. (n = 311,879). SelectMDx after negative MRI (2) resulted in a health gain of 0.008 and 0,011 QALY per patient using the SPCG and PIVOT data.. Cost savings were $436 per patient and about $136 million for the yearly population. Conclusions: The use of SelectMDx to guide prostate biopsy decision-making can improve health outcomes and lower costs. Cost savings were highest when SelectMDx was used before MRI to select patients for MRI and biopsy. With respect to health gain, the use of SelectMDx after negative MRI was most beneficial when assuming higher mortality for missed PCa (SPCG). When the mortality was assumed to be lower (PIVOT) SelectMDx should be used before MRI to result in the highest health gain.