Hansen NL, et al. – The purpose of this study was to analyze sub–differentiation of prostate imaging–reporting and data system–3 prostate lesions using pre–defined T2– and diffusion–weighted (DWI) MRI criteria, to aid the biopsy decision process. The obtained data indicate that identification of certain objective imaging criteria as well as a subjective biopsy recommendation from an experienced radiologist can help to increase the predictive value of equivocal prostate lesions and inform the decision making process of whether or not to biopsy.

Methods

• For this study, 143 patients with PIRADS-3 index lesions on MRI underwent targeted transperineal-MR/US fusion biopsy.
• In this study, radiologists with 2 and 7-years experience performed blinded retrospective second-reads using set criteria and assigned biopsy recommendations.
• They computed and compared inter-reader agreement, Gleason score (GS), positive (PPV) predictive values (±95% confidence intervals) by Fisher’s exact test with Bonferroni-Hom correction.

Results

• It was noted that 43% (61/143) patients had GS 6-10 and 21% (30/143) Gleason score (GS) ≥3 + 4 cancer.
• For peripheral zone lesions, they observed significant differences in any cancer detection for shape (0.26 ± 0.13 geographical vs. 0.69 ± 0.23 rounded; p = 0.0055) and ADC (mild 0.21 ± 0.12 vs marked 0.81 ± 0.19; p = 0.0001).
• For transition zone, they observed significantly increased cancer detection for location (anterior 0.63 ± 0.15 vs. mid/posterior 0.31 ± 0.14; p = 0.0048), border (pseudo-capsule 0.32 ± 0.14 vs. ill-defined 0.61 ± 0.15; p = 0.0092), and ADC (mild 0.35 ± 0.12 vs marked restriction 0.68 ± 0.17; p = 0.0057).
• According to the results, biopsy recommendations had 62% inter-reader agreement (89/143).
• The obtained data indicate that experienced reader PPVs were significantly higher for any cancer with “biopsy-recommended” 0.61 ± 0.11 vs. “no biopsy” 0.21 ± 0.10 (p = 0.0001), and for GS 7-10 cancers: 0.32 ± 0.10 vs. 0.08 ± 0.07, respectively (p = 0.0003).