In this study, the authors assess their institutional experience of men who underwent an mpMRI and TPM following an initially negative TRUS prostate biopsy. In a 3-year period, there were 70 patients who met the study criteria; median age was 66 years (43–81) years and median prostate-specific antigen (PSA) 9.6 ug/L (0.7–33.9).
PCa was detected in the TPM in 43 (56%) patients, and 34 (82%) patients had Gleason score ≥7 lesions. PIRADS 4/5 lesion was seen in 34 (47%), and 26 (76%) of these had PCa concordance with biopsy results. Overall, location concordance with MRI findings was seen in 32 (46%) patients, but discordance was due to benign histology in 28 (38%). Patients with proven PCa had 74% concordance with MRI.
At the end of the day, this implies that 40% of PCa diagnoses were discordant with mpMRI findings. An important conclusion that the authors draw is that a targeted biopsy in the absence of a concurrent systematic 12-core biopsy is not appropriate in this population.
However, this is a small population of selected patients. A trial of patients, similar to the PROMIS study,1 which was done in biopsy naïve patients, would be better able to answer this question. While I agree with the authors that a systematic biopsy is still warranted on repeat biopsy to evaluate for cancers not detectable on MRI, further evidence is required.
Presented By: Ewan Semple, Core Surgical Trainee, Department of Urology, Ninewells Hospital, Dundee, United Kingdom
Co-Authors: Hassen Ahmeidat, Ghulam Nabi, Ghulam M Nandwani
Institutions: Ninewells Hospital, NHS Tayside, Dundee, United Kingdom
Written By: Thenappan Chandrasekar, MD (Clinical Fellow, University of Toronto Twitter: @tchandra_uromd at the 72nd Canadian Urological Association Annual Meeting - June 24 - 27, 2017 - Toronto, Ontario, Canada
1. Ahmed HU, El-Shater Bosaily A, Brown LC, Gabe R, Kaplan R, Parmar MK, Collaco-Moraes Y, Ward K, Hindley RG, Freeman A, Kirkham AP7, Oldroyd R, Parker C, Emberton M; PROMIS study group. Diagnostic accuracy of multi-parametric MRI and TRUS biopsy in prostate cancer (PROMIS): a paired validating confirmatory study. Lancet. 2017 Feb 25;389(10071):815-822. doi: 10.1016/S0140-6736(16)32401-1. Epub 2017 Jan 20.