Prostate-specific membrane antigen (PSMA) positron emission tomography/computed tomography (PET/CT) can detect multiparametric magnetic resonance imaging (mpMRI)-invisible prostate tumours and improve the sensitivity of detection of prostate cancer (PCa) in comparison to mpMRI alone. Numerous risk calculators have been validated as tools for stratification of men at risk of being diagnosed with clinically significant (cs)PCa.
To develop a novel risk calculator using clinical parameters and imaging parameters from mpMRI and PSMA PET/CT in a cohort of patients undergoing mpMRI and PSMA PET/CT before biopsy.
A total of 291 men from the PRIMARY prospective trial underwent mpMRI and PSMA PET/CT before transperineal prostate biopsy with sampling of systematic and targeted cores.
Novel risk calculators were developed using multivariable logistic regression analysis to predict detection of overall PCa (International Society of Urological Pathology grade group [GG] ≥1) and csPCa (GG ≥2). The risk calculators were then compared with the European Randomised Study of Screening for Prostate Cancer risk calculator incorporating mpMRI (ERSPC-MRI). Resampling methods were used to evaluate the discrimination and calibration of the risk calculators and to perform decision curve analysis.
Age, prostate-specific antigen, prostate volume, and mpMRI Prostate Imaging-Reporting and Data System scores were included in the MRI risk calculator, resulting in area under the receiver operating characteristic curve (AUC) values of 0.791 for overall PCa (GG ≥1) and 0.812 for csPCa (GG ≥2). Addition of the maximum standardised uptake value (SUVmax) on PSMA PET/CT for the prostate lesion, and of SUVmax for the mpMRI lesions for the MRI-PSMA risk calculator resulted in AUCs of 0.831 for overall PCa and 0.876 for csPCa (≥ISUP2).The ERSPC-MRI risk calculator had AUCs of 0.758 (p = 0.02) for overall PCa and 0.805 (p = 0.001) for csPCa. Both the MRI and MRI-PSMA risk calculators were superior to the ERSPC-MRI for both overall PCa and csPCa.
These novel risk calculators incorporate clinical and radiological parameters for stratification of men at risk of csPCa. The risk calculator including PSMA PET/CT data is superior to a calculator incorporating mpMRI data alone.
We evaluated a new risk calculator that uses clinical information and results from two types of scan to predict the risk of clinically significant prostate cancer on prostate biopsy. This risk model can guide patients and clinicians in shared decision-making and may help in avoiding unnecessary prostate biopsies.
European urology open science. 2023 Jun 02*** epublish ***
Brian D Kelly, Gideon Ptasznik, Matthew J Roberts, Paul Doan, Phillip Stricker, James Thompson, James Buteau, Kenneth Chen, Omar Alghazo, Jonathan S O'Brien, Michael S Hofman, Mark Frydenberg, Nathan Lawrentschuk, Dara Lundon, Declan G Murphy, Louise Emmett, Daniel Moon
Division of Cancer Surgery, Peter MacCallum Cancer Centre, Melbourne, Australia., Royal Brisbane and Women's Hospital, Brisbane, Australia., Garvan Institute of Medical Research, Darlinghurst, Australia., St. Vincent's Prostate Cancer Centre, Darlinghurst, Australia., Department of Urology, St. George Hospital, Australia., Department of Molecular Imaging and Therapeutic Nuclear Medicine, Cancer Imaging and Prostate Cancer Theranostics and Imaging Centre of Excellence, Peter MacCallum Cancer, Melbourne, Australia., Department of Surgery, Monash University and Cabrini Institute, Cabrini Health, Melbourne, Australia., Department of Theranostics and Nuclear Medicine, St. Vincent's Hospital Sydney, Darlinghurst, Australia.