Faculty Bibliography

BACKGROUND: A systematic literature review of magnetic resonance imaging (MRI)-targeted prostate biopsy demonstrates poor adherence to the Standards for the Reporting of Diagnostic Accuracy (STARD) recommendations for the full and transparent reporting of diagnostic studies. OBJECTIVE: To define and recommend Standards of Reporting for MRI-targeted Biopsy Studies (START). DESIGN, SETTING, AND PARTICIPANTS: Each member of a panel of 23 experts in urology, radiology, histopathology, and methodology used the RAND/UCLA appropriateness methodology to score a 258-statement premeeting questionnaire. The collated responses were presented at a face-to-face meeting, and each statement was rescored after group discussion. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Measures of agreement and consensus were calculated for each statement. The most important statements, based on group median score, the degree of group consensus, and the content of the group discussion, were used to create a checklist of reporting criteria (the START checklist). RESULTS AND LIMITATIONS: The strongest recommendations were to report histologic results of standard and targeted cores separately using Gleason score and maximum cancer core length. A table comparing detection rates of clinically significant and clinically insignificant disease by targeted and standard approaches should also be used. It was recommended to report the recruitment criteria for MRI-targeted biopsy, prior biopsy status of the population, a brief description of the MRI sequences, MRI reporting method, radiologist experience, and image registration technique. There was uncertainty about which histologic criteria constitute clinically significant cancer when the prostate is sampled using MRI-targeted biopsy, and it was agreed that a new definition of clinical significance in this setting needed to be derived in future studies. CONCLUSIONS: Use of the START checklist would improve the quality of reporting in MRI-targeted biopsy studies and facilitate a comparison between standard and MRI-targeted approaches.

PURPOSE: An optimal prostate biopsy in clinical practice is based on a balance among adequate detection of clinically significant prostate cancers (sensitivity), assuredness regarding the accuracy of negative sampling (negative predictive value), limited detection of clinically insignificant cancers and good concordance with whole gland surgical pathology results to allow accurate risk stratification and disease localization for treatment selection. Inherent within this optimization is variation of the core number, location, labeling and processing for pathological evaluation. To date, there is no consensus in this regard. The purpose of this review is to 1) define the optimal number and location of biopsy cores during primary prostate biopsy among men with suspected prostate cancer, 2) define the optimal method of labeling prostate biopsy cores for pathological processing which will provide relevant and necessary clinical information for all potential clinical scenarios, and 3) determine the maximal number of prostate biopsy cores allowable within a specimen jar which would not preclude accurate histological evaluation of the tissue. MATERIALS AND METHODS: A bibliographic search using PubMed(R) covering the period up to July 2012 yielded approximately 550 articles. Articles were reviewed and categorized based on which of the 3 objectives of this review was addressed. Data were extracted, analyzed and summarized. Recommendations are provided based on this literature review and our clinical experience. RESULTS: The use of 10 to 12-core extended sampling protocols increases cancer detection rates compared to traditional sextant sampling methods and reduces the likelihood of repeat biopsy by increasing negative predictive value, ultimately allowing more accurate risk stratification without increasing the likelihood of detecting insignificant cancers. As the number of cores increases above 12, the increase in diagnostic yield becomes marginal. Only limited evidence supports the use of initial biopsy schemes involving more than 12 cores or saturation. Apical and laterally directed sampling of the peripheral zone increases cancer detection rate, reduces the need for repeat biopsies and predicts pathological features on prostatectomy while transition zone biopsies do not. There are little data to suggest that knowing the exact site of an individual positive biopsy core provides meaningful clinical information. However, determining laterality of cancer on biopsy may be helpful for predicting sites of extracapsular extension and therapeutic planning. Placement of multiple biopsy cores in a single container (greater than 2) appears to compromise pathological evaluation, which can reduce cancer detection rate and increase the likelihood of equivocal diagnoses. CONCLUSIONS: A 12-core systematic biopsy that incorporates apical and far-lateral cores in the template distribution allows maximal cancer detection, avoids repeat biopsy, and provides information adequate for identifying men who need therapy and planning that therapy while minimizing the detection of occult, indolent prostate cancers. This literature review does not provide compelling evidence that individual site specific labeling of cores benefits clinical decision making regarding the management of prostate cancer. Based on the available literature, we recommend packaging no more than 2 cores in each jar to avoid reduction of the cancer detection rate through inadequate tissue sampling.

OBJECTIVE: To determine whether suspicion for tumor on prostate MRI incorporating T2-weighted imaging (T2-WI) and diffusion-weighted imaging (DWI) predicts more adverse pathology on radical prostatectomy (RP). METHODS: From 2007 to 2009, 154 patients underwent 1.5 Tesla pelvic-phased-array magnetic resonance imaging (MRI) of the prostate that included T2-WI and DWI before RP. MRI examinations were retrospectively reviewed and grouped by degree of suspicion for tumor: no suspicion for tumor (NST, n = 15), equivocal suspicion for tumor (EST, n = 60), or strong suspicion for tumor (SST, n = 79). The NST/EST groups were combined and compared to the SST group. Preoperative variables were used to assemble a multivariate model. Outcomes reflective of adverse pathology included primary Gleason grade >/=4, pathologic stage >/=T3 (>/=pT3), and tumor upgrading. Subgroup analysis was performed for patients meeting eligibility criteria for active surveillance (n = 55). For this analysis, the NST group was compared to the EST/SST groups. RESULTS: SST status was associated with adverse preoperative risk factors for aggressive disease. Univariate analysis demonstrated significant association between SST and primary Gleason >/=4 pathology and stage >/=pT3 (P <.05). On multivariate analysis, SST was independently predictive of primary Gleason >/=4 pathology (odds ratio [OR] 6.14, 95% confidence interval [CI] 1.97-19.2) and Gleason upgrading (OR 2.47, 95% CI 1.01-6.02). Among patients eligible for active surveillance, those in the NST group had decreased likelihood of Gleason >/=7 disease or stage >/=pT3 compared to the EST/SST groups (7.7% vs 47.6%, P = .01). CONCLUSION: Increased tumor suspicion on T2-WI/DWI MRI is indicative of adverse pathology on RP. These findings suggest a role for MRI in pretreatment risk assessment.