Contrast-free MRI-first screening in young asymptomatic men: Prostate characteristics and cancer detection rates
摘要
Early-onset prostate cancer is becoming increasingly prevalent, and MRI-first strategies are gaining interest as a potential screening tool. However, MRI characteristics of the prostate in younger men remain underexplored. This study aimed to characterize prostate MRI features in a young, asymptomatic male cohort undergoing contrast-free biparametric MRI for prostate cancer screening, to determine the detection rate of clinically significant prostate cancer, and to identify clinical and imaging predictors of clinically significant disease.
MethodsA total of 659 prostate MRIs were acquired; after excluding men who declined biopsy, 641 participants formed the final cohort. Peripheral-zone signal patterns on T2-weighted imaging (T2WI), diffusion-weighted imaging (DWI), and apparent diffusion coefficient (ADC) maps were assessed by two blinded radiologists. PI-RADS scores were assigned independently. Men with PI-RADS ≥ 4 were offered targeted MRI–TRUS fusion biopsy (PI-RADS 3 in case of PSAD ≥ 0.16). Multivariable logistic regression was performed to identify independent predictors of csPCa.
ResultsMedian PSA 1.02 ng/mL (IQR 0.58–2.03) and PSA density (PSAD) 0.03 ng/mL/mL (IQR 0.02–0.05). The most common peripheral-zone appearance was heterogeneous T2 hypointensity (74.7%), homogeneous DWI hyperintensity (59.4%), and homogeneous ADC hypointensity (66.1%). PI-RADS distribution was: 0.5% PI-RADS 1, 81.1% PI-RADS 2, 14.2% PI-RADS 3, 3.6% PI-RADS 4, and 0.6% PI-RADS 5. Forty-one men (6.4%) underwent biopsy, yielding 5 ciPCa, 23 csPCa, and 13 negative results, corresponding to csPCa in 3.6% of the entire cohort. In multivariable analysis, PSAD ≥ 0.15 ng/mL/mL, PI-RADS 4–5, and family history were independently associated with csPCa (all p < 0.01).
ConclusionsContrast-free bpMRI effectively characterizes prostate morphology in younger men and identifies csPCa at an early stage. PSAD, PI-RADS category, and family history significantly enhance risk stratification, supporting the integration of bpMRI-based approaches into future MRI-first screening strategies for younger, asymptomatic populations.