STOCKHOLM, SWEDEN (UroToday.com) - Dr. M. R. Pokorny presented the first data on a multicenter, prospective, investigator-blinded, study in a single cohort of biopsy-naive men from Europe and Austrailia. They compared transrectal ultrasound guided biopsy (TRUSGB) with multiparamteric MRI (mpMRI) based prostate biopsy. Their hypothesis was that an image based triage process using 3T mpMRI will reduce over diagnosis and the need for biopsy in men found to have an elevated PSA.
The study enrolled 2 223 consecutive biopsy-naïve men with elevated PSA. All underwent mpMRI. Images were evaluated by 3 independent readers using a structured reporting system. Subjects with no suspicion of significant cancer underwent TRUSGB only. Subjects with suspicion of significant CaP underwent MRI guided biopsies (MRGB) with 2-4 cores sampled, followed by TRUSGB performed by a second urologist blinded to the MRI and MRGB findings, using a standard 12-core template. MRGB was performed prone, in the MRI scanner, using only conscious sedation. All cores were analyzed by a single uropathologist who was also blinded to the origin of each core.
They reported that MRGB alone reduced the number of men with elevated PSA, requiring biopsy, by 51%, reduced the incidence of a biopsy-determined diagnosis of histologically insignificant prostate cancer by 90%, and increased the number of histologically significant cancers detected by17%. Moreover, MRGB also reduced the required number of biopsy cores by 87.9% from 2 672 cores (TRUSGB) to 322 cores. They reported an estimated NPV of TRUSGB and MRGB for a biopsy diagnosis of "no significant prostate cancer” of 71.9% and 96.9%, respectively. The estimated sensitivity of TRUSGB and MRGB for a biopsy diagnosis of “significant prostate cancer” was reported as 70.4% and 92.3%, respectively.
Over the last couple of years, the use of PSA as a screening test for prostate cancer in asymptomatic males has been criticized. This is mostly attributed to the fact that men with an elevated PSA generally undergo TRUSGB, which the literature suggests can result in over-diagnosis of non-life threatening cancer. In this study, the authors suggest that for asymptomatic men with elevated PSA, selective use of targeted biopsy following mpMRI imaging reduces over diagnosis of insignificant CaP and increases the detection of significant CaP compared to TRUS-guided random biopsies.
Presented by M. R. Pokorny at the 29th Annual European Association of Urology (EAU) Congress - April 11 - 15, 2014 - Stockholmsmässan - Stockholm, Sweden.
The Wesley Hospital, Department of Urology, Brisbane, Australia
Written by Reza Mehrazin, MD, medical writer for UroToday.com