Session: MP40: Prostate Cancer: Detection & Screening I
MP40-17: Clinical and high-resolution micro-ultrasound risk factors for detecting clinically significant prostate cancer in men with PI-RADS 3 lesions: update from a large single center experience.
Introduction: Multiparametric magnetic resonance imaging (mpMRI) is an invaluable diagnostic tool in prostate biopsies (PBx) decision making. However, most Prostate Imaging–Reporting and Data System (PI-RADS) 3 lesions do not contain clinically significant prostate cancer (CSPCa; grade group =2). This study is an update of a previous study aimed to investigate clinical and high-resolution micro-ultrasound (microUS) derived risk factors that predict CSPCa in men with PI-RADS 3 lesions. Methods: A total of 200 patients who underwent microUS-guided PBx with the ExactVu system for a PI-RADS 3 lesion were prospectively enrolled between October 2017 and September 2022. The Prostate Risk Identification using microUS (PRI-MUS) protocol was used to identify suspicious areas; PBx included targeted and systematic sampling. The primary endpoint was the assessment of microUS diagnostic accuracy in detecting csPCa. Secondary endpoints included determining: the proportion of patients with a PIRADS 3 lesion who may avoid PBx after microUS examination; predictors of csPCa in patients presenting with PI-RADS 3 lesions. Results: Median patient age was 64 (IQR 58–69) years, median total PSA was 6 (IQR 4.5–8.4) ng/mL and median prostate volume was 51.6 (IQR 35–73.7) mL. Overall, 91 (45.5%) patients were in the repeat biopsy setting. Micro-US detected prostate lesions with a PRI-MUS score of 3, 4 and 5 in respectively 47 (35.3%), 63 (47.4%) and 23 (17.3%) patients, while in 67 (33.5%) individuals micro-US did not identify any target. Overall, 44 (22.0%) harbored csPCa. Considering csPCa detection rate, microUS showed optimal sensitivity and negative predictive value (respectively 95.4% and 97.0%), while specificity and positive predictive value were 41.6% and 31.6%, respectively. 65 (32.5%) patients with negative microUS examination could have avoided PBx with 2 (4.5%) missed csPCa. In multivariable logistic regression models (MLRMs), positive microUS, age, and PSA density =0.15 emerged as independent predictors of PCa. The accuracy of a model including PRI-MUS score, age, PSA density, family history and previous biopsies was 0.764 (95% CI: 0.673 - 0.854). Conclusions: Our update findings confirm that MicroUS could represent a helpful tool capable of discriminating patients harbouring csPCa among subjects with PI-RADS 3 lesion. Further studies are still needed to corroborate our findings and to better establish the role of this promising strategy within the diagnostic work up of PCa patients. SOURCE OF Funding: none
