Comparison of MR/Ultrasound Fusion–Guided Biopsy With Ultrasound-Guided Biopsy for the Diagnosis of Prostate Cancer

Abstract

Importance Targeted magnetic resonance (MR)/ultrasound fusion prostate biopsy has been shown to detect prostate cancer. The implications of targeted biopsy alone vs standard extended-sextant biopsy or the 2 modalities combined are not well understood. Objective To assess targeted vs standard biopsy and the 2 approaches combined for the diagnosis of intermediate- to high-risk prostate cancer. Design, Setting, And Participants Prospective cohort study of 1003 men undergoing both targeted and standard biopsy concurrently from 2007 through 2014 at the National Cancer Institute in the United States. Patients were referred for elevated level of prostate-specific antigen (PSA) or abnormal digital rectal examination results, often with prior negative biopsy results. Risk categorization was compared among targeted and standard biopsy and, when available, whole-gland pathology after prostatectomy as the “gold standard.” Interventions Patients underwent multiparametric prostate magnetic resonance imaging to identify regions of prostate cancer suspicion followed by targeted MR/ultrasound fusion biopsy and concurrent standard biopsy. Main Outcomes And Measures The primary objective was to compare targeted and standard biopsy approaches for detection of high-risk prostate cancer (Gleason score ≥4 + 3); secondary end points focused on detection of low-risk prostate cancer (Gleason score 3 + 3 or low-volume 3 + 4) and the biopsy ability to predict whole-gland pathology at prostatectomy. Results Targeted MR/ultrasound fusion biopsy diagnosed 461 prostate cancer cases, and standard biopsy diagnosed 469 cases. There was exact agreement between targeted and standard biopsy in 690 men (69%) undergoing biopsy. Targeted biopsy diagnosed 30% more high-risk cancers vs standard biopsy (173 vs 122 cases, P < .001) and 17% fewer low-risk cancers (213 vs 258 cases, P < .001). When standard biopsy cores were combined with the targeted approach, an additional 103 cases (22%) of mostly low-risk prostate cancer were diagnosed (83% low risk, 12% intermediate risk, and 5% high risk). The predictive ability of targeted biopsy for differentiating low-risk from intermediate- and high-risk disease in 170 men with whole-gland pathology after prostatectomy was greater than that of standard biopsy or the 2 approaches combined (area under the curve, 0.73, 0.59, and 0.67, respectively; P < .05 for all comparisons). Conclusions and Relevance Among men undergoing biopsy for suspected prostate cancer, targeted MR/ultrasound fusion biopsy, compared with standard extended-sextant ultrasound-guided biopsy, was associated with increased detection of high-risk prostate cancer and decreased detection of low-risk prostate cancer. Future studies will be needed to assess the ultimate clinical implications of targeted biopsy. Trial Registration clinicaltrials.gov Identifier: NCT00102544

EAU-ESTRO-SIOG Guidelines on Prostate Cancer. Part 1: Screening, Diagnosis, and Local Treatment with Curative Intent

“…The combination of systematic and targeted biopsies (MRI-Tbx) may also better predict the final GS [29]. As a result, some authors proposed performing systematic mpMRI before prostate biopsy [30,31]. One metaanalysis suggested that MRI-Tbx had a higher detection rate of clinically significant PCa compared to TRUS biopsy (sensitivity 0.91 vs. 0.76) and a lower rate of detection of insignificant PCa (sensitivity 0.44 vs. 0.83).…”

Re: Prostate Cancer Detection with Magnetic Resonance-ultrasound Fusion Biopsy: The Role of Systematic and Targeted Biopsies

“…However, the significance and extent of combined systematic biopsies remains controversial. Siddiqui et al detected after adding systematic to targeted biopsy in their cohort of 1003 patients with a positive mpMRI 29 (2.9%) additional csPCa cases [2]. That resulted in the significantly higher number of 35 patients needed to be biopsied additionally with the systematic approach to detect one csPCa case.…”

Early detection of prostate cancer: can we have our cake and eat it too?

“…Fusion of archived multiparametric MRI images with live transrectal US has allowed for improved diagnostics and targeting. A recent publication from the National Cancer Institute reported on 1003 men undergoing targeted and standard biopsies between 2007 and 2014 [23]. The primary objective was to compare detection of higher risk cancer of the prostate, with secondary objectives assessing detection of lower risk disease and predictive capabilities of fusion biopsies for whole gland pathology at time of radical prostatectomy.…”