Diagnostic value of prostate imaging reporting and data system version 1 and 2 in detection of prostate cancer in transition zone

Objective To evaluate the diagnostic value of prostate imaging reporting and data system version 1 (PI-RADS V1) and version 2 (PI-RADS V2) for detection of prostate cancer (PCa) in the transition zone (TZ). Methods Seventy-seven patients with suspicious lesions in TZ on mpMRI were scored according to the PI-RADS system (V1 and V2) before MR-TRUS fusion guided biopsy prospectively. In all of the patients with suspicious tumors, respectively at least one lesion with a PI-RADS V1 assessment category of ≥3, was selected for biopsy.Independent sample t test was used to compare scores of PI-RADS V1 and V2 between PCa and benign prostatic hyperplasia (BPH). The diagnostic performance of PI-RADS V1 and V2 for detection of PCa in the transition zone was compared by analyzing ROC basing on the results of MR-TRUS fusion guided biopsy. Results A cohort of 77 patients was performed including 31 cases of PCa (32 cores) and 46 cases of BPH (51 cores). PCa (V1:11.50±2.79; V2:4.28±0.99) had significantly higher scores of both PI-RADS V1 and PI-RADS V2 than BPH(V1:7.51±1.63; V2:2.61±0.67) (P<0.05). Using a PI-RADS V1 score cut-off ≥ 11, sensitivity and specificity in group PCa and BPH were calculated, which were 68.8%(22/32) and 96.1%(49/51) with a area under curve of 0.869; using a PI-RADS V2 score cut-off ≥ 4, which were 75.0% (24/32) and 90.2% (46/51) with a area under curve of 0.888, respectively. Conclusions PI-RADS system can indicate the likelihood of PCa of suspicious lesions in TZ on Mp-MRI. PI-RADS V2 perform better than V1 for the assessment of prostate cancer in TZ. Key words: Prostatic neoplasms; Magnetic resonance imaging; Prostate imaging reporting and data system; Comparative study