Multiparametric MRI (mpMRI) and biopsy-based molecular tests such as the 17-gene Oncotype DX®Genomic Prostate Score™ (GPS) assay are increasingly used to improve risk stratification in men with clinically localized prostate cancer (PCa). The GPS assay was previously shown to be a significant independent predictor of adverse pathology (AP) at radical prostatectomy (RP) in men diagnosed with systematic biopsies only. We therefore investigated the ability of GPS to predict AP in the setting of MRI-guided prostate biopsy.
We identified men diagnosed with NCCN very low/low/intermediate-risk PCa who underwent simultaneous mpMRI fusion-targeted and systematic prostate biopsy with subsequent RP within 6 months. GPS testing was performed on biopsy tissue of the highest Gleason score (GS). The primary outcome was AP (GS≥4+3 and/or pT3+ at RP). Independent predictors of AP were determined using a multivariable model to adjust for clinical parameters.
134 men were eligible for primary analysis. In univariable analysis, UCLA MRI score, GPS results and biopsy GS were significant predictors of AP. After multivariable adjustment, GPS values remained a significant predictor of AP (OR for GPS per 20 units 3.28, 95%CI 1.74-6.62, p<0.001). A wide and overlapping distribution of GPS results were seen across PI-RADSv2 scores.
The GPS result is an independent predictor of AP in patients who were diagnosed with very low/low/intermediate-risk PCa in the setting of mpMRI-fusion prostate biopsy. This assay can be useful as an independent or adjunct technology to mpMRI for individualizing risk stratification in low and intermediate risk PCa.
The Journal of urology. 2018 Mar 07 [Epub ahead of print]
Amirali Salmasi, Jonathan Said, Alan W Shindel, Pooria Khoshnoodi, Ely R Felker, Anthony E Sisk, Tristan Grogan, Debbie McCullough, John Bennett, Helen Bailey, H Jeffrey Lawrence, David A Elashoff, Leonard S Marks, Steven S Raman, Phillip G Febbo, Robert E Reiter
Institute of Urologic Oncology, Department of Urology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA., Department of Pathology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA., Genomic Health Inc, Redwood City, CA., Department of Radiology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA., Department of Medicine Statistics Core, David Geffen School of Medicine, University of California, Los Angeles, California, United States of America., Institute of Urologic Oncology, Department of Urology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA; Department of Radiology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA., Institute of Urologic Oncology, Department of Urology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA; Jonsson Comprehensive Cancer Center, David Geffen School of Medicine, University of California, Los Angeles,. Electronic address: .