Fig. 1

A-D. Exemplar case where MRI changed both clinical stage and biopsy grade: 66-year-old biopsy-naïve patient, PSA 19 ng/mL. A, B: T2 axial images show a large 29 × 22 mm lesion centred on the central zone (arrow in A), with clear seminal vesicle invasion seen on sagittal imaging (arrow in B). C, D: The lesion demonstrates marked restricted diffusion on ADC maps (C) and clear early enhancement on DCE (D). Target cores demonstrated Gleason 4 + 5 = 9 (Grade Group 5), systematic cores however showed right-sided Gleason grade 4 + 3 = 7 (Grade group 3). The location in the central zone make systematic cores less likely to sample the tumour core, with additional T3b disease shown on MRI. The prognostic group changed from CPG3 to CPG5. E–F Exemplar case where clinical and MRI based investigations concurred: 52-year-old biopsy naïve patient, PSA 16.4 ng/mL. A, B: bilaterally PZ lesions with low T2 signal (E) and matching restricted diffusion on ADC map (F), measuring up to 15 mm in the right mid PZ (arrows) and 13 mm in the left mid PZ. Right-side target cores demonstrated Gleason grade 3 + 4 = 7 (Grade Group 2) and left targets exhibited Gleason grade 3 + 3 = 6 (Grade Group 1), replacing approximately 79% of cores. Systematic biopsy showed Gleason grade 3 + 4 = 7 (Grade Group 2). The large size of the lesions and in the mid gland PZ posteriorly, ensured adequate sampling by systematic biopsy. The prognostic group was unchanged as CPG2. (CPG—NICE Cambridge Prognostic Group model)