Multiparametric MRI guidance in first-time prostate biopsies: what is the real benefit?

Abstract

PURPOSE With the increased recognition of the capabilities of prostate multiparametric (mp) magnetic reso-nance imaging (MRI), attempts are being made to incorporate MRI into routine prostate biopsies. In this study, we aimed to analyze the diagnostic yield via cognitive fusion, transrectal ultrasound (TRUS)-guided, and in-bore MRI-guided biopsies in biopsy-naive patients with positive findings for prostate cancer screening. METHODSCharts of 140 patients, who underwent transrectal prostate biopsy after the adaptation of mp-MRI into our routine clinical practice, were reviewed retrospectively. Patients with previous negative bi-opsies (n=24) and digital rectal examination findings suspicious for >=cT3 prostate cancer (n=16) were excluded. T2-weighted imaging, diffusion-weighted imaging, and dynamic contrast-enhanced im-aging were included in mp-MRI. Cognitive fusion biopsies were performed after a review of mp-MRI data, whereas TRUS-guided biopsies were performed blinded to MRI information. In-bore biopsies were conducted by means of real-time targeting under MRI guidance. RESULTSBetween January 2012 and February 2014, a total of 100 patients fulfilling the inclusion cri-teria underwent TRUS-guided (n=37), cognitive fusion (n=49), and in-bore (n=14) biop-sies. Mean age, serum prostate specific antigen level, and prostate size did not differ signifi-cantly among the study groups. In TRUS-guided biopsy group, 51.3% were diagnosed with prostate cancer, while the same ratio was 55.1% and 71.4% in cognitive fusion and in-bore bi-opsy groups, respectively (P = 0.429). Clinically significant prostate cancer detection rate was 69.1%, 70.3%, and 90% in TRUS-guided, cognitive fusion, and in-bore biopsy groups, respectively (P = 0.31). According to histopathologic variables in the prostatectomy specimen, significant prostate cancer was detected in 85.7%, 93.3%, and 100% of patients in TRUS-guided, cognitive fusion, and in-bore biopsy groups, respectively. CONCLUSIONIn the first set of transrectal prostate biopsies, mp-MRI guidance did not increase the diagnostic yield significantly.