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.
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Siddiqui MM,1 Rais-Bahrami S,2 Turkbey B,3 George AK, Rothwax J,4 Shakir N,4 Okoro C,4 Raskolnikov D,4 Parnes HL,5 Linehan WM,4 Merino MJ,6 Simon RM,7 Choyke PL,3 Wood BJ,8 Pinto PA8 Are you the author?
1Urologic Oncology Branch, National Cancer Institute, National Institutes of Health, Bethesda, Maryland; Dr Siddiqui is now with the Department of Surgery, Division of Urology, University of Maryland, Baltimore.
2Urologic Oncology Branch, National Cancer Institute, National Institutes of Health, Bethesda, Maryland; Dr Rais-Bahrami is now with the Departments of Urology and Radiology, University of Alabama at Birmingham.
3Molecular Imaging Program, National Cancer Institute, National Institutes of Health, Bethesda, Maryland.
4Urologic Oncology Branch, National Cancer Institute, National Institutes of Health, Bethesda, Maryland.
5Division of Cancer Prevention, National Cancer Institute, National Institutes of Health, Bethesda, Maryland.
6Laboratory of Pathology, National Cancer Institute, National Institutes of Health, Bethesda, Maryland.
7Biometric Research Branch, Division of Cancer Treatment and Diagnosis, National Cancer Institute, National Institutes of Health, Rockville, Maryland.
8Urologic Oncology Branch, National Cancer Institute, National Institutes of Health, Bethesda, Maryland; Center for Interventional Oncology, Department of Radiology and Imaging Sciences, NIH Clinical Center and National Cancer Institute, National Institutes.
Reference: JAMA. 2015 Jan 27;313(4):390-7.