Urinary Molecular Biomarker Test Impacts Prostate Biopsy Decision-making in Clinical Practice

Introduction:There is an unmet need for noninvasive methods to better identify patients at increased risk for clinically significant prostate cancer. SelectMDx (R) is a molecular urine test validated for the detection of Gleason score 7 and higher cancers (ISUP [International Society of Urological Pathology] Grade Group 2-5). In this multicenter trial we evaluated the test's impact on prostate biopsy decision making in clinical practice.Methods:The study involved 5 U.S. community urology practices which sequentially enrolled 418 patients who received a SelectMDx test between May 2016 and April 2017 while undergoing evaluation for initial prostate biopsy. All tests were ordered by the urologist for patient management. We determined biopsy and prostate cancer detection rates in patients with SelectMDx positive versus SelectMDx negative results.Results:Of the 418 subjects evaluated with SelectMDx 253 (61%) had negative results and 165 (39%) had positive results. Subsequent biopsy rates for SelectMDx positive and negative cases were 60% (99) and 12% (32), respectively (p <0.001). Time from SelectMDx result to biopsy was shorter for those with positive vs negative results (median 2 vs 5 months, p=0.001). Of patients who underwent biopsy within 3 months of testing 71 (43%) with positive results underwent biopsy and 27 had cancers identified, including 10 greater than Grade Group 2. Of 9 patients with SelectMDx negative results (3.6%) who underwent biopsy 4 were diagnosed with cancer, all Grade Group 2 or less.Conclusions:SelectMDx had a significant impact on initial prostate biopsy decision making. Biopsy rates in SelectMDx positive cases were fivefold higher than in SelectMDx negative cases. These results describe the clinical utility of SelectMDx in real-world community urology practice.