The role of quantitative MRI-based prostate zonal parameters in predicting clinically significant prostate cancer A U.S. cohort.

Introduction: We aimed to investigate the clinical utility of quantitative prostatic zonal measurements on multiparametric magnetic resonance imaging (mpMRI) for the predication of clinically significant prostate cancer (csPCa).

Methods: A retrospective, single-institution study included 144 men who underwent mpMRI from 2015-2017. Prostate zone parameters were measured on mpMRI. Correlation and multivariable analysis evaluated the relationship between prostate zone parameters and the presence of csPCa.

Results: The mean age was 66.9±7.8 years old. The median (interquartile range [IQR]) prostate volume and prostate-specific antigen (PSA) were 51.6 ml (37.1-74.5) and 6.1 ng/ ml (4.5-8.2), respectively. Men with csPCa had significantly smaller total prostate volume (TPV), transitional zone volume (TZV), and transitional zone thickness (TZT), and larger transitional zone density (TZD) compared to those without PCa; however, on multivariate variable analysis, only TZD maintained significance. TZD had a comparable area under the curve to PSA density (PSAD) and PSA (0.74 vs. 0.73 vs. 0.60, respectively). In a subgroup analysis of men with PCa, PSAD and TZD were significantly higher in men with Gleason grade group (GG) ≥2 compared to those with GG <2 (p=0.002); however, this significance is not maintained on logistic regression in predicting GG.

Conclusions: Quantitative features of prostate zones on MRI may aid in identifying better predictors of csPCa. Zonal-based PSA density (TZD) may be a useful marker in identifying csPCa. Further exploration is needed to understand the clinical application of larger TZV in men with csPCa compared to those with insignificant disease.