Faculty Bibliography

BACKGROUND:Diffusion-weighted imaging (DWI) provides insight into the pathophysiology underlying renal dysfunction. Variants of DWI include intravoxel incoherent motion (IVIM), which differentiates between microstructural diffusion and vascular or tubular flow, and diffusion tensor imaging (DTI), which quantifies diffusion directionality. PURPOSE/OBJECTIVE:To investigate the reproducibility of joint IVIM-DTI and compare controls to presurgical renal mass patients. STUDY TYPE/METHODS:Prospective cross-sectional. SUBJECTS/METHODS:Thirteen healthy controls and ten presurgical renal mass patients were scanned. Ten controls were scanned twice to investigate reproducibility. FIELD STRENGTH/SEQUENCE/UNASSIGNED:Subjects were scanned on a 3T system using 10 b-values and 20 diffusion directions for IVIM-DTI in a study approved by the local Institutional Review Board. ASSESSMENT/RESULTS:Retrospective coregistration and measurement of joint IVIM-DTI parameters were performed. STATISTICAL ANALYSIS/METHODS:Parameter reproducibility was defined as intraclass correlation coefficient (ICC) >0.7 and coefficient of variation (CV) <30%. Patient data were stratified by lesion side (contralateral/ipsilateral) for comparison with controls. Corticomedullary differentiation was evaluated. RESULTS:In controls, the reproducible subset of REnal Flow and Microstructure AnisotroPy (REFMAP) parameters had average ICC = 0.82 and CV = 7.5%. In renal mass patients, medullary fractional anisotropy (FA) was significantly lower than in controls (0.227 ± 0.072 vs. 0.291 ± 0.044, P = 0.016 for the kidney contralateral to the mass and 0.228 ± 0.070 vs. 0.291 ± 0.044, P = 0.018 for the kidney ipsilateral). In the kidney ipsilateral to the mass, cortical Dp,radial was significantly higher than in controls (P = 0.012). Conversely, medullary Dp,axial was significantly lower in contralateral than ipsilateral kidneys (P = 0.027) and normal controls (P = 0.044). DATA CONCLUSION/UNASSIGNED:REFMAP-MRI parameters provide unique information regarding renal dysfunction. In presurgical renal mass patients, directional flow changes were noted that were not identified with IVIM analysis alone. Both contralateral and ipsilateral kidneys in patients show reductions in structural diffusivities and anisotropy, while flow metrics showed opposing changes in contralateral vs. ipsilateral kidneys. LEVEL OF EVIDENCE/METHODS:2 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2018.

Purpose of Review: The widely acknowledged limitations of the standard prostate cancer (PCa) diagnostic paradigm have provided an impetus to explore novel imaging modalities to diagnose, localize, and risk stratify PCa. As the body of literature focused on HistoScanningTM(HS) grows, there is need for a comprehensive review of the clinical efficacy of this technology. Recent Findings: Eighteen original, English language articles were found to adequately study the use of HistoScanningTM for prostate cancer diagnosis in the clinical setting. The articles were found by conducting a bibliographic search of PubMed in April 2017 in addition to utilizing references. The studies are divided into four groups based on study design. Study methods and quantitative data are summarized for each of the relevant articles. The results are synthesized to evaluate the utility of HistoScanningTM for the purpose of diagnosing PCa. Summary: Despite the promise of early pilot studies, there is a lack of consistent results across a number of further investigations of HistoScanningTM. This becomes increasingly evident as study size increases. As various other modern diagnostic modalities continue to develop, the future of HistoScanningTM, both alone and in conjunction with these technologies, remains unclear.

PURPOSE OF REVIEW: The widely acknowledged limitations of the standard prostate cancer (PCa) diagnostic paradigm have provided an impetus to explore novel imaging modalities to diagnose, localize, and risk stratify PCa. As the body of literature focused on HistoScanning(HS) grows, there is need for a comprehensive review of the clinical efficacy of this technology. RECENT FINDINGS: Eighteen original, English language articles were found to adequately study the use of HistoScanning for prostate cancer diagnosis in the clinical setting. The articles were found by conducting a bibliographic search of PubMed in April 2017 in addition to utilizing references. The studies are divided into four groups based on study design. Study methods and quantitative data are summarized for each of the relevant articles. The results are synthesized to evaluate the utility of HistoScanning for the purpose of diagnosing PCa. Despite the promise of early pilot studies, there is a lack of consistent results across a number of further investigations of HistoScanning. This becomes increasingly evident as study size increases. As various other modern diagnostic modalities continue to develop, the future of HistoScanning, both alone and in conjunction with these technologies, remains unclear.

OBJECTIVE: To provide a multi-institutional analysis of clinical factors predicting unplanned hospital readmission after major inpatient urologic surgery. MATERIALS AND METHODS: The American College of Surgeons National Surgical Quality Improvement Program (NSQIP) is a risk-adjusted data collection mechanism for analyzing clinical outcomes data including 30-day perioperative readmissions and complications. We identified 23,108 patients who underwent major inpatient urologic surgery from 2011 to 2012. Readmission rates were determined and stratified by procedure type. Multiple logistic regression was used to determine independent risk factors for 30-day unplanned hospital readmissions. RESULTS: Of 23,108 total patients undergoing urologic surgery, 1329 patients (5.8%) had unplanned readmissions. Upper tract reconstruction and urinary diversion without cystectomy (21/102) and cystectomy (291/1,662) had the highest rates of readmission of all procedures analyzed. Readmitted patients had a 64.2% (853/1329) and 64.4% (855/1329 patients) rate of major and minor complications, respectively, compared to 6.7% (1459/21779) and 15.9% (3462/21779) for patients not readmitted (p<0.02). Organ space infection (OR 15.23), pulmonary embolism (OR 12.14), deep venous thrombosis (OR 10.96), and return to the operating room (OR 8.46) were the most substantial predictors of readmission. Laparoscopic/robotic procedures had significantly lower readmission rates compared to open procedures for prostatectomy, partial nephrectomy, and nephrectomy (p<0.01). CONCLUSIONS: Readmission after inpatient urological surgery occurs at a rate of 5.8%, with cystectomy and urinary diversion demonstrating the highest rates. Major and minor postoperative complications were the most substantial predictors of readmission. These results may guide risk reduction initiatives to prevent readmissions after major urologic surgery.

The primary goal of a focal therapy treatment paradigm is to achieve cancer control through targeted tissue destruction while simultaneously limiting deleterious effects on peri-prostatic structures. Focal therapy approaches are employed in several oncologic treatment protocols, and have been shown to provide equivalent cancer control for malignancies such as breast cancer and renal cell carcinoma. Efforts to develop a focal therapy approach for prostate cancer have been challenged by several concepts including the multifocal nature of the disease and limited capability of prostate ultrasound and systematic biopsy to reliably localize the site(s) and aggressiveness of disease. Multi-parametric MRI (mpMRI) of the prostate has significantly improved disease localization, spatial demarcation and risk stratification of cancer detected within the prostate. The accuracy of this imaging modality has further enabled the urologist to improve biopsy approaches using targeted biopsy via MRI-ultrasound fusion. From this foundation, an improved delineation of the location of disease has become possible, providing a critical foundation to the development of a focal therapy strategy. This chapter reviews the accuracy of mpMRI for detection of "aggressive" disease, the accuracy of mpMRI in determining the tumor volume, and the ability of mpMRI to accurately identify the index lesion. While mpMRI provides a critical, first step in developing a strategy for focal therapy, considerable questions remain regarding the relationship between MR identified tumor volume and pathologic tumor volume, the accuracy and utility of mpMRI for treatment surveillance and the optimal role and timing of follow-up mpMRI.

INTRODUCTION: Surgical treatment of penile cancer is usually associated with mutilation; alterations in self-esteem and body image; affecting sexual and urinary functions; and declined health-related quality of life. Recently, organ sparing treatment has appeared and led to limiting these complications. MATERIAL AND METHODS: An extensive review of the literature concerning penile-preserving strategies was conducted. The focus was put on indications, general principles of management, surgical options and reconstructive techniques, the most common complications, as well as functional and oncological outcomes. RESULTS: Analyzed methods, e.g.: topical chemotherapy, laser ablation therapy, radiotherapy, Moh's microscopic surgery, circumcision, wide local excision, glans resurfacing and glansectomy are indicated in low-stage tumors (Tis, Ta-T2). After glansectomy, reconstruction is also possible. CONCLUSIONS: Organ sparing techniques may achieve good anatomical, functional, and psychological outcomes without compromising local cancer control, which depends on early diagnosis and treatment. Penile sparing strategies are acceptable treatment approaches in selected patients with low-stage penile cancer after establishing disease-risk and should be considered in this population.

INTRODUCTION: Multiparametric-MRI (mp-MRI) is an evolving noninvasive imaging modality that increases the accurate localization of prostate cancer at the time of MRI targeted biopsy, thereby enhancing clinical risk assessment, and improving the ability to appropriately counsel patients regarding therapy. MATERIAL AND METHODS: We used MEDLINE/PubMed to conduct a comprehensive search of the English medical literature. Articles were reviewed, data was extracted, analyzed, and summarized. In this review, we discuss the mp-MRI prostate exam, its role in targeted prostate biopsy, along with clinical applications and outcomes of MRI targeted biopsies. RESULTS: Mp-MRI, consisting of T2-weighted imaging, diffusion-weighted imaging, dynamic contrast-enhanced imaging, and possibly MR spectroscopy, has demonstrated improved specificity in prostate cancer detection as compared to conventional T2-weighted images alone. An MRI suspicion score has been developed and is depicted using an institutional Likert or, more recently, a standardized reporting scale (PI-RADS). Techniques of MRI-targeted biopsy include in-gantry MRI guided biopsy, TRUS-guided visual estimation biopsy, and software co-registered MRI-US guided biopsy (MRI-US fusion). Among men with no previous biopsy, MRI-US fusion biopsy demonstrates up to a 20% increase in detection of clinically significant cancers compared to systematic biopsy while avoiding a significant portion of low risk disease. These data suggest a potential role in reducing over-detection and, ultimately, over-treatment. Among men with previous negative biopsy, 72-87% of cancers detected by MRI targeted biopsy are clinically significant. Among men with known low risk cancer, repeat biopsy by MR-targeting improves risk stratification in selecting men appropriate for active surveillance secondarily reducing the need for repetitive biopsy during surveillance. CONCLUSIONS: Use of mp-MRI for targeting prostate biopsies has the potential to reduce the sampling error associated with conventional biopsy by providing better disease localization and sampling. MRI-ultrasound fusion-targeted prostate biopsy may improve the identification of clinically significant prostate cancer while limiting detection of indolent disease, ultimately facilitating more accurate risk stratification. Literature supports the clinical applications of MRI-targeted biopsy in men who have never been biopsied before, those with a prior negative biopsy, and those with low risk disease considering active surveillance.