Case Report: Radical prostatectomy without prostate biopsy in PI-RADS 5 lesions on 3T multi-parametric MRI of the prostate gland

Abstract

Objective: Current practice mandates a prostate biopsy for histological confirmation of prostate cancer prior to a radical prostatectomy. Prostate biopsy, whether performed trans-rectally or trans-perineally, is an invasive procedure which typically involves an anaesthetic and has the risks of urosepsis, bleeding and haematoma. Post-biopsy inflammatory changes can also obliterate natural tissue planes thereby potentially compromising the quality of a nerve sparing procedure and increasing positive margin rates.3T-Multi-Parametric Magnetic Resonance Imaging of the Prostate (3T mpMRI-P) is gaining increasing acceptance in the identification and localisation of prostate cancer. In experienced centres, the positive predictive value has been reported to be as high as 95%.Methods: Two patients with rising and elevated age- adjusted PSAs and palpable malignant prostate nodules on Digital Rectal Examination (DRE) underwent 3T mpMRI-P. Both patients had Prostate Imaging-Reporting and Data System (PI-RADS) 5 lesions in their peripheral zones corresponding to palpable nodules. Prostate biopsies were offered but declined by both patients. Both were satisfied that there was sufficient evidence on their PSA, DRE and 3T mpMRI-P for a diagnosis of prostate cancer without prostate biopsies and both elected to proceed to a Da Vinci Robotic Assisted Laparoscopic Radical Prostatectomy (RALRP).Results: Unilateral nerve sparing RALRPs were performed on both patients without complication. Histology demonstrated Gleason 4+4=8 and 4+3=7 prostate adenocarcinomas, with tumour volumes of 14.92cc and 4.5cc respectively.Conclusions: In appropriately counselled patients who have a high pre-test probability of prostate cancer (rising and elevated PSA, malignant nodule on DRE and a corresponding PI-RADS 5 lesion on 3T mpMRI-P), it may be appropriate to proceed to a radical prostatectomy without a tissue diagnosis if the patients have strong reservations about prostate biopsy.