| Abstract: |
Objectives: To measure the performance characteristics of combined T 2-weighted (T2W) and diffusion-weighted (DW) magnetic resonance imaging (MRI) suspicion scoring prior to MR-transrectal ultrasound (TRUS) fusion template transperineal (TTP) re-biopsy. Methods: Thirty-nine patients referred for prostate re-biopsy, with prior MRI examinations, were retrospectively included. The MR images, including T2W and DW-MRI, had been independently evaluated prospectively by two radiologists using a structured scoring system. An MR-TRUS fusion TTP re-biopsy was used for MR target and non-targeted biopsy cores. Targeting performance and correlation with disease status were evaluated on a per-patient and per-region basis. Results: The cancer yield was 41 % (16/39 patients). MR targeting accurately detected the disease in 12/16 (75 %) cancerous patients and missed the disease in 4/16 (25 %) patients, all with Gleason 3+3 disease. There was a significant relationship (P<0.01) between MR suspicion score and the significance of cancer. Reader 1 had significantly higher sensitivity in the transition zone (TZ; 0.84) compared with the peripheral zone (PZ; 0.32) (P=0.04). Inter-reader agreement was moderate for the PZ and substantial for the TZ. Conclusions: MRI targeting is beneficial in the setting of TTP MR-TRUS fusion re-biopsy and MR suspicion score relates to prostate cancer clinical significance. A T2W and DW-MRI structured scoring system results in good inter-reader agreement in this setting. Key Points: • Pre-biopsy MRI aids the detection of high significance cancer during prostate re-biopsy. • MRI suspicion level correlates with the clinical significance of prostate cancer detected. • T 2 W and DW-MRI structured scoring of pre-biopsy MRI permits good inter-reader agreement. © 2014 European Society of Radiology. |
