PI-RADS Committee Position on MRI Without Contrast Medium in Biopsy-Naive Men With Suspected Prostate Cancer: Narrative Review.

The steadily increasing demand for diagnostic prostate MRI has led to concerns regarding the lack of access to and the availability of qualified MRI scanners and sufficiently experienced radiologists, radiographers, and technologists to meet the demand. Solutions must enhance operational benefits without compromising diagnostic performance, quality, and delivery of service. Solutions should also mitigate risks such as decreased reader confidence and referrer engagement. One approach may be the implementation of MRI without the use gadolinium-based contrast medium (bipara-metric MRI), but only if certain prerequisites such as high-quality imaging, expert interpretation quality, and availability of patient recall or on-table monitoring are mandated. Alternatively, or in combination, a clinical risk-based approach could be used for protocol selection, specifically, which biopsy-naive men need MRI with contrast medium (multiparametric MRI). There is a need for prospective studies in which biopsy decisions are made according to MRI without contrast enhancement. Such studies must define clinical and operational benefits and identify which patient groups can be scanned successfully without contrast enhancement. These higher-quality data are needed before the Prostate Imaging Reporting and Data System (PI-RADS) Committee can make evidence-based recommendations about MRI without contrast enhancement as an initial diagnostic approach for prostate cancer workup.

Performance of PI-RADS v2 assessment categories assigned prior to MR-US fusion biopsy in a new fusion biopsy program.

OBJECTIVE: To validate the performance of PI-RADS v2 for detection of clinically significant prostate cancer (csPca, Gleason ≥7) within the context of a new fusion biopsy program. MATERIAL AND METHODS: Patients with a PI-RADS v2 assessment category assigned on pre-biopsy mpMRI between March 2015 and November 2017 were identified. Diagnostic performance of PI-RADS v2 was calculated using fusion biopsy results as reference standard using receiver operating characteristic curve analysis. Patient and lesion characteristics were analyzed with one-way ANOVA and Wilcoxon rank sum test. RESULTS: Of 83 patients with 175 lesions, 115/175 (65.7%) were benign, 21/175 (12%) were Gleason 6, and 39/175 (22.3%) were Gleason ≥7. csPCa rates were 0% (0/5) for PI-RADS 1, 7.4% (2/27) for PI-RADS 2, 5.8% (3/52) for PI-RADS 3, 31.2% (24/77) for PI-RADS 4, and 71.4% (10/14) for PI-RADS 5 (p < 0.0001). For prediction of csPCa, patient-level AUC was 0.68 and lesion-level AUC was 0.77. Biopsy threshold of PI-RADS ≥3 was 92.6% sensitive and 22.1% specific. A threshold of PI-RADS ≥4 was 87.2% sensitive and 58.1% specific. Rate of csPca detection on concurrent standard 12 core biopsy only was 6.7%. CONCLUSION: PI-RADS v2 assessment categories assigned prior to biopsy predict pathologic outcome reasonably well in a new prostate fusion biopsy program. Biopsy threshold of PI-RADS ≥3 is highly sensitive. A threshold of ≥4 increases specificity but misses some csPCa.

The evolving role of diet in prostate cancer risk and progression.

PURPOSE OF REVIEW: This overview examines the rationale for dietary interventions for prostate cancer by summarizing the current evidence base and biological mechanisms for the involvement of diet in disease incidence and progression. RECENT FINDINGS: Recent data have further solidified the association between insulin resistance and prostate cancer with the homeostatic model assessment of insulin resistance. Data also show that periprostatic adipocytes promote extracapsular extension of prostate cancer through chemokines, thereby providing a mechanistic explanation for the association observed between obesity and high-grade cancer. Regarding therapeutics, hyperinsulinemia may be the cause of resistance to phosphatidylinositol-3 kinase inhibitors in the treatment of prostate cancer, leading to new investigations combining these drugs with ketogenic diets. SUMMARY: Given the recently available data regarding insulin resistance and adipokine influence on prostate cancer, dietary strategies targeting metabolic syndrome, diabetes, and obesity should be further explored. In macronutrient-focused therapies, low carbohydrate/ketogenic diets should be favored in such interventions because of their superior impact on weight loss and metabolic parameters and encouraging clinical data. Micronutrients, including the carotenoid lycopene which is found in highest concentrations in tomatoes, may also play a role in prostate cancer prevention and prognosis through complementary metabolic mechanisms. The interplay between genetics, diet, and prostate cancer is an area of emerging focus that might help optimize therapeutic dietary response in the future through personalization.

Twitter Mentions and Academic Citations in the Urologic Literature.

OBJECTIVE: To quantify the relationship between the number of Twitter mentions and the number of academic citations a urologic publication receives. MATERIALS AND METHODS: Two hundred and thirteen papers from 7 prominent urologic journals were examined 37 months after publication. Articles were evaluated with 2 citation based "bibliometrics" (Scopus, Google Scholar) and Twitter mentions were tracked using the Altmetric Bookmarklet. The number of article citations and Twitter mentions were compared using one-way Analysis of variance (ANOVA) and bivariate fit analysis. RESULTS: Seventy-three percent of articles had at least 1 Twitter mention. Forty-two percent of Twitter mentions occurred within the first week of the online publication date. Articles mentioned on Twitter had 2.0-fold more Scopus citations (P <.01), and 2.3-fold more Google Scholar citations (P <. 01) compared to articles with no Twitter mentions. Female urologic articles had the greatest number of Twitter mentions (5.7 mentions/article) while pediatric urology had the fewest mean number of Twitter mentions (0.8 mentions/article). A total of 8.9% of papers were tweeted by their authors. Author tweeted articles were associated with a 12.3 (2.0-fold) and 15.5 (1.8-fold) mean citation increase for Scopus and Google Scholar (P <. 01 and P = . 01) compared to articles not shared by their authors on Twitter. CONCLUSION: The majority of urologic publications are being shared on Twitter. The number of citations a urologic publication receives up to 3 years after release is positively associated with the number of mentions it has on Twitter. Twitter activity may be an early indicator of ultimate academic impact of an academic urologic paper.

Distinguishing pediatric and adolescent renal cell carcinoma from other renal malignancies.

PURPOSE: Renal cell carcinoma (RCC) represents a small proportion of renal malignancies early in life. Distinguishing RCC from other malignancies is important as treatment strategies may differ. We analyze the Surveillance Epidemiology, and End Results (SEER) database to identify predictive factors of RCC in the pediatric population with renal tumors. METHODS: We queried SEER to identify patients from ages 0 to 19 diagnosed with a renal malignancy between 1973 and 2013. Cases were sorted using histology and site codes. Age-adjusted standardized incidence rates (SIR) were calculated. We compared differences in characteristics between cancer types. A logistic regression model and a nomogram were created to identify predictors of RCC. RESULTS: A total of 3,670 patients were identified, of which 281 (7.7%) were diagnosed with RCC. The SIR of RCC increased with age. After age 12, RCC was found in >50% of all newly diagnosed cases. On multivariate analysis, RCC was associated with smaller tumor size (P < 0.001), increasing age (P < 0.001), black race (P < 0.001), and localized stage (P < 0.001). The nomogram predicted RCC pathology with a concordance index of 0.965. CONCLUSIONS: RCC in childhood and adolescence is relatively uncommon; however, it accounts for >50% of renal malignancies after age 12. For every year of increasing age, the odds of having an RCC diagnosis are increased by 50%. The odds of a renal tumor being RCC are increased in black children, those with localized disease, and those with smaller tumors. In these specific populations, RCC should be favored in the differential diagnosis of the renal mass.

Preoperative Multiparametric Magnetic Resonance Imaging Predicts Biochemical Recurrence in Prostate Cancer after Radical Prostatectomy.

OBJECTIVES: To evaluate the utility of preoperative multiparametric magnetic resonance imaging (MP-MRI) in predicting biochemical recurrence (BCR) following radical prostatectomy (RP). MATERIALS/METHODS: From March 2007 to January 2015, 421 consecutive patients with prostate cancer (PCa) underwent preoperative MP-MRI and RP. BCR-free survival rates were estimated using the Kaplan-Meier method. Cox proportional hazards models were used to identify clinical and imaging variables predictive of BCR. Logistic regression was performed to generate a nomogram to predict three-year BCR probability. RESULTS: Of the total cohort, 370 patients met inclusion criteria with 39 (10.5%) patients experiencing BCR. On multivariate analysis, preoperative prostate-specific antigen (PSA) (p = 0.01), biopsy Gleason score (p = 0.0008), MP-MRI suspicion score (p = 0.03), and extracapsular extension on MP-MRI (p = 0.03) were significantly associated with time to BCR. A nomogram integrating these factors to predict BCR at three years after RP demonstrated a c-index of 0.84, outperforming the predictive value of Gleason score and PSA alone (c-index 0.74, p = 0.02). CONCLUSION: The addition of MP-MRI to standard clinical factors significantly improves prediction of BCR in a post-prostatectomy PCa cohort. This could serve as a valuable tool to support clinical decision-making in patients with moderate and high-risk cancers.

The use of whole organ decellularization for the generation of a vascularized liver organoid.

UNLABELLED: A major roadblock to successful organ bioengineering is the need for a functional vascular network within the engineered tissue. Here, we describe the fabrication of three-dimensional, naturally derived scaffolds with an intact vascular tree. Livers from different species were perfused with detergent to selectively remove the cellular components of the tissue while preserving the extracellular matrix components and the intact vascular network. The decellularized vascular network was able to withstand fluid flow that entered through a central inlet vessel, branched into an extensive capillary bed, and coalesced into a single outlet vessel. The vascular network was used to reseed the scaffolds with human fetal liver and endothelial cells. These cells engrafted in their putative native locations within the decellularized organ and displayed typical endothelial, hepatic, and biliary epithelial markers, thus creating a liver-like tissue in vitro. CONCLUSION: These results represent a significant advancement in the bioengineering of whole organs. This technology may provide the necessary tools to produce the first fully functional bioengineered livers for organ transplantation and drug discovery.