Faculty Bibliography

PURPOSE: Following an initial negative biopsy, there is an ongoing need for strategies to improve patient selection for repeat biopsy as well as the diagnostic yield from repeat biopsies. MATERIALS AND METHODS: As a collaborative Initiative of the American Urological Association and the Society of Abdominal Radiology's Prostate Cancer Disease-Focused Panel, an expert panel of urologists and radiologists conducted a literature review and formed consensus statements regarding the role of prostate MRI and MRI-targeted biopsy in patients with a negative biopsy, which are summarized in this review. RESULTS AND CONCLUSION: s: The panel recognizes that many options exist for men with a previously negative biopsy. If a biopsy is recommended, prostate MRI and subsequent MRI-targeted cores appear to facilitate the detection of CS disease over standardized repeat biopsy. Thus, when high-quality prostate MRI is available, it should be strongly considered in any patient with a prior negative biopsy who has persistent clinical suspicion for prostate cancer and who is under evaluation for a possible repeat biopsy. The decision whether to perform MRI in this setting must also take into account results of any other biomarkers, the cost of the examination, as well as availability of high quality prostate MRI interpretation. If MRI is done, it should be performed, interpreted, and reported in accordance with PI-RADS V2 guidelines. Experience by the reporting radiologist and biopsy operator are required to achieve optimal results and practices integrating prostate MRI into patient management are advised to implement quality assurance programs to monitor targeted biopsy results. Patients receiving a PI-RADS assessment category of 3-5 warrant repeat biopsy with image guided targeting. While TRUS-MRI fusion or in-bore MRI-targeting may be valuable for more reliable targeting, especially for MRI lesions that are small or in difficult locations, in the absence of such targeting technologies, cognitive (visual) targeting remains a reasonable approach in skilled hands. At least two targeted cores should be obtained from each MRI-defined target. Given a number of studies showing a proportion of missed CS cancers by MRI-targeted cores, a case-specific decision must be made whether to also perform concurrent systematic sampling. However, performing solely targeted biopsy should only should be considered once quality assurance efforts have validated the performance of prostate MRI interpretations with results consistent with the published literature. In patients with a negative or low-suspicion MRI (PI-RADS assessment category of 1 or 2, respectively), other ancillary markers (i.e., PSA, PSAD, PSAV, PCA3, PHI, 4K) may be of value to identify patients warranting repeat systematic biopsy, although further data is needed on this topic. If a repeat biopsy is deferred on the basis of the MRI findings, then continued clinical and laboratory follow-up is advised and consideration should be given to incorporating repeat MRI in this diagnostic surveillance regimen.

Multiparametric MRI of the prostate demonstrates strong potential to address many limitations of traditional prostate cancer diagnosis and management strategies. Recent evidence supports roles for prostate MRI in prebiopsy risk stratification, guidance of targeted biopsy and preoperative disease staging. Prostate MRI may also assist the planning and follow-up of investigational partial gland ablative therapies. This article reviews the impact of prostate MRI on such diagnostic and therapeutic paradigms in contemporary prostate cancer management.

OBJECTIVES: To evaluate the cancer detection rates (CDR) for men undergoing 12 core systematic prostate biopsy with negative prebiopsy mpMRI (NegMR). MATERIALS & METHODS: Clinical data from consecutive men undergoing prostate biopsy with prebiopsy 3T mpMRI from December 2011 to August 2014 were reviewed from an IRB approved prospective database. Prebiopsy mpMRI was read by a single radiologist and men with NegMR prior to biopsy were identified for this analysis. Clinical features, CDR, and NPV rates were summarized. RESULTS: Seventy five men underwent SPB with a NegMRI during the study period. For the entire cohort, men with no prior biopsy, men with prior negative biopsy, and men enrolled in active surveillance protocols, overall CDR was 18.7%, 13.8%, 8.0% and 38.1%, respectively, and detection of Gleason sum >/= 7 (GS>/=7) cancer was 1.3%, 0%, 4.0% and 0%, respectively. The NPV for all cancers was 81.3%, 86.2%, 92.0%, and 61.9%, and for GS>/=7 cancer was 98.7%, 100%, 96.0% and 100%, respectively. CONCLUSIONS: Negative prebiopsy mpMRI confers an overall NPV of 82% on 12 core biopsy for all cancer and 98% for GS>/=7. Based upon biopsy indication, these findings assist in prebiopsy risk stratification for detection of high risk disease and may provide guidance in the decision to pursue biopsy