Comparison of initial and second opinion reads of multiparametric magnetic resonance imaging of the prostate for transperineal template-guided biopsies with MRI-Ultrasound fusion.

Purpose: To investigate the value of second-opinion evaluation of multiparametric prostate magnetic resonance imaging (MRI) by subspecialised uroradiologists for the detection of significant cancer in transperineal fusion prostate biopsy.

Methods: The evaluated data included age, PSA (ng/ml), PSA density, Gleason score, digital rectal examination (DRE), prostate volume of 149 patients. Twenty-seven patients (18%) had no previous prostate biopsy, 114 patients (77%) had a previous negative biopsy, and 8 patients (5%) were on active surveillance. Using PI-RADS v2 scores for mpMRI a second report was performed by a specialist uroradiologist. In all cases a subsequent transperineal biopsy was performed with at least 2 cores per target and additional background systemic cores. Initial and second-opinion radiology reports were evaluated for detection of any cancer and Gleason score (GS) 7-10 cancer, including positive predictive value and negative (NPV) and compared by Fisher's exact test.

Results: At transperineal biopsy, 51 % (76/149) of patients had a GS 6-10 prostate cancer (PCa), 27 % (40/149) of patients had a GS 3 + 3 PCa and 12 % (18/149) a GS 3 + 4 and 12 % (18/149) had a GS ≥4 + 3 PCa. Agreement between initial and second-opinion reads was observed in 57.7% (86/149; kappa value = 0.32). The detection of clinically significant cancers with second-opinion reads was significantly higher (0.61; 17/28) compared to initial reads (0.35; 17/49); P = 0.034.

Conclusions: Second reading of prostate mpMRIs by subspecialised uroradiologists significantly improved the positive predictive value for detection of clinically significant prostate cancer and showed a trend towards improved NPV for MRI-negative cases where biopsy could be safely avoided. Urologists should be aware that the experience of the reporter will affect the report when making decisions if and how to obtain biopsies. Reporter experience may help to reduce overcalling and avoid over-targeting of lesions.