Introduction: PSA screening and multi parametric MRI are widely used to identify patients with suspected prostate cancer who may benefit from prostate biopsy. Patients with PIRADs scores 3-5 are typically biopsied, however up to 17% of patients with PIRADs scores of 1-2 will harbour clinically significant cancers that would remain undiagnosed using these criteria, while up to 80% of PIRADs 3 patients do not have clinically significant cancers. Hence there is a requirement for additional tests better able to guide prostate biopsy decisions. MiCheck Prostate is a serum-based test for aggressive prostate cancer (GS3+4 or higher) developed by Minomic International that uses a proprietary algorithm to combine results from three standard blood markers with clinical factors to provide a risk score for clinically significant cancer. The current study was designed to assess the test performance of MiCheck Prostate in an Australian study cohort. Methods: The study was conducted at Macquarie University Hospital (MUH, Ethics approval 5201500707). Serum samples were collected from patients undergoing prostate biopsies. Blood markers were measured at Douglass Hanley Moir (DHM) laboratories using Abbott Architect and Alinity immunoassays. Results: 192 patient samples were collected: 78 (41%) had no cancer, 37 (19%) had insignificant cancer (Gleason 3+3) and 77 (40%) had Gleason 3+4 or higher. 2 (1%) patients had PIRADs 1, 16 (8%) had PIRADS 2, 23 (12%) PIRADs 3, 88 (46%) had PIRADs 4 and 55 (29%) had PIRADs 5 and 8 (4%) patients had no PIRADs data. When used prior to MRI, MiCheck Prostate had 92% sensitivity for detection of clinically significant cancers. The AUC for MiCheck Prostate was significantly higher than PSA (0.71 vs 0.58, p = 0.03). When used post MRI, MiCheck Prostate showed sensitivity of 94% and specificity of 39% for detection of significant prostate cancer in the overall patient population. The AUC for MiCheck Prostate was significantly higher than PSA (0.79 vs 0.58, p <0.0001). In 49 patients with PIRADs score of 3 or lower, MiCheck Prostate showed sensitivity of 92% and specificity of 65%, with NPV of 96%. Conclusions: The current study demonstrates MiCheck Prostate has high sensitivity for detection of significant prostate cancer in an Australian population. MiCheck Prostate has high sensitivity in both the pre-MRI and post-MRI settings as well as in the PIRADs 1-3 subgroup. MiCheck Prostate provides additional information to urologists and patients in the decision to proceed to prostate biopsy with patients suspected of having prostate cancer. SOURCE OF Funding: Minomic International Ltd, Australian Government SIEF
