Single‑center, retrospective, evaluator‑blinded, pilot and pivotal clinical trials: Assessing the mirCaP Kit (hsv2‑miR‑H9/hsa‑miR‑3659) as a diagnostic marker for prostate cancer in patients with PSA levels in the gray zone

Prostate-specific antigen (PSA) remains a key biomarker for the diagnosis and monitoring of prostate cancer (PCa). For patients within the 'PSA gray zone', the positive predictive value (PPV) of PSA for PCa detection by biopsy is estimated to be between 30 and 42%. In the present study, a single-center, retrospective, evaluator-blinded, pilot and pivotal clinical trial was performed to assess the clinical performance of the mirCaP kit (Urotech, Inc.), which measures the herpes simplex virus 2-microRNA (miR)-H9/hsa-miR-3659 ratio, with respect to helping physicians make appropriate decisions regarding further assessment of patients with PSA levels within this gray zone. For the patients in the initial clinical trial group who were in the PSA gray zone, the sensitivity, specificity, accuracy, PPV and negative predictive value (NPV) of the mirCaP kit were 94.29, 77.50, 85.33, 78.57 and 93.94%, respectively. For those in the pivotal clinical trial, these values were 94.50, 82.73, 87.90, 81.10 and 95.04%, respectively. These results suggest that the mirCaP kit may be an effective non-invasive diagnostic marker for PCa in patients with PSA levels in the gray zone. Thus, the mirCaP kit is a promising tool that can help physicians make a decision regarding the need for prostate biopsy in these patients. Of note, the NPV of >90% indicates that the mirCaP kit could prevent unnecessary prostate biopsies in >90% of these cases.