Prospective Randomized Trial Comparing the Safety and Clarity of Water Versus Saline Irrigant in Ureteroscopy.

BACKGROUND: Water irrigant is discouraged in ureteroscopy due to risks demonstrated in more invasive endoscopic procedures. However, water is not well studied in ureteroscopy and may provide better visualization than standard saline. OBJECTIVE: To determine whether water irrigant increases the risk of hyponatremia compared with saline and provides better visualization in ureteroscopy. DESIGN, SETTING, AND PARTICIPANTS: A randomized, prospective, double-blinded trial was conducted. In 2017, eligible adult ureteroscopy patients at a university hospital were recruited for the study. INTERVENTION: Participants randomized to water or saline irrigant in ureteroscopy. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Serum sodium and osmolality, body temperature, subjective surgeon visualization, and objective turbidity clarity were analyzed. Chi-square or Fisher's exact tests for categorical variables and analysis of variance test for continuous variables were performed. RESULTS AND LIMITATIONS: A total of 121 individuals (mean age 57 ± 15 yr) underwent ureteroscopy (mean time 35 ± 18 min) with a mean irrigation volume of 839 ± 608 ml. For the 101 (83%) patients who had nephrolithiasis, the mean number of stones was 2 ± 1 and the mean stone burden was 13 ± 7 mm. There were no significant differences in demographic, clinical, and intraoperative variables between water and saline groups, except for a higher body mass index in the saline group (p = 0.01). There was no significant difference between groups in the incidence of hyponatremia, hypo-osmolality, or hypothermia. The median surgeon visualization score was significantly higher using water (p < 0.01). The mean turbidity was significantly lower with water (p = 0.02). Limitations were not objectively assessing hemolysis or fluid absorption. CONCLUSIONS: Water irrigant does not increase the incidence of hyponatremia in uncomplicated ureteroscopy and provides clearer visualization than saline. PATIENT SUMMARY: We compared safety and clarity of water and saline irrigation, which aid surgeon visualization, in ureteroscopy, which can treat kidney stones. We found that water irrigant does not reduce blood sodium levels significantly compared with saline in ureteroscopy and provides better visualization.

Experienced bedside-assistants improve operative outcomes for surgeons early in their learning curve for robot assisted laparoscopic radical prostatectomy.

Robot-assisted laparoscopic radical prostatectomy (RALP) relies heavily on the bedside assistant (BA). Currently, the relationship between BA experience and surgical outcomes in robotic surgery is not clear. We examined whether bedside assistant experience can significantly affect positive margin rate and peri-operative outcomes for RALP for surgeons within their learning curve. A retrospective cohort study of a single surgeon's peri-operative outcomes during RALP was examined and compared with and without an experienced bedside assistant. Patient demographic data and peri-operative data, margin rate, and length of stay (LOS), were collected and analyzed. Univariate and multivariable analyses were performed to determine if expert BA was a predictor of post-operative outcomes. In total, 170 consecutive cases over three years were analyzed. 111 (65%) were performed without an expert BA. The two groups were not significantly different with regards patient demographics (p > 0.05). On univariate analysis, having an expert BA was associated with a significantly lower LOS (31 h ± 21 vs. 42 h ± 26, p = 0.004), EBL (296 ml ± 180 vs. 441 ml ± 305, p < 0.0001) and positive margin rate (20% vs. 37%, p = 0.03). Other surgical outcomes were comparable between groups. On multivariable analysis, expert BA remained a predictor of, EBL (B stat = - 146, 95% CI - 240 to - 52, p = 0.003) and positive margin rate (OR 0.4, 95% CI 0.2-0.96, p = 0.04). Our results demonstrate that the use of an expert BA may result in improved patient outcomes early in the learning curve of RALP, most notably, positive margin rate and estimated blood loss.

Exuberant Malakoplakia of the Prostate Presenting as Prostatic Abscesses in an Immunocompromised Patient.

Background: Malakoplakia is a rare benign lesion, usually associated with deficient intralysosomal degradation of microorganisms, more commonly, Escherichia coli. Malakoplakia occurs in various organ systems, the most frequently affected site being the urinary bladder. We report a rare case of isolated extensive malakoplakia involving the prostate, diagnosed on transurethral resection performed for radiologically suspected prostatic abscesses. Case Presentation: A 61-year-old African American male presented with symptoms of urinary obstruction for the past 2 months. His medical history was significant for immunosuppression (liver transplantation 3 months prior and diabetes mellitus). He reported four episodes of E. coli-associated urinary tract infection after his liver transplantation. Serum prostate specific antigen was 1.83 ng/cc (normal inferior to 4 ng/cc), and urine culture was positive for E. coli sensitive to ceftriaxone. Pelvic magnetic resonance imaging was suggestive of prostatitis with prostatic abscesses; cystoscopy was unremarkable. The patient was started on intravenous ceftriaxone therapy. A standard bipolar transurethral resection of the prostate was performed, and purulent-like material was encountered in the resected tissue. Histologic examination demonstrated extensive infiltration and replacement of the prostatic tissue by sheets of pink histiocytes with targetoid inclusions consistent with Michaelis-Gutmann bodies, ultimately confirming malakoplakia of the prostate. Conclusion: Prostatic malakoplakia is an unexpected diagnosis in patients suspected of having malignancy or prostatitis. Its exact pathogenesis is unknown, but it involves defective bacterial degradation after phagocytosis. E. coli is often cultured from the patients' urine. Immunosuppression, present in our patient, is a well-known associated factor. Prostatic malakoplakia can radiologically masquerade as prostatic adenocarcinoma, despite the use of cutting-edge imaging technology. With the growing use of multiparametric 3T prostate magnetic resonance imaging to screen for prostate cancer, it is possible that urologists, radiologists, and pathologists will encounter prostatic malakoplakia more frequently in the future.

Efficacy of Percutaneous Tibial Nerve Stimulation for Overactive Bladder in Women and Men at a Safety Net Hospital.

PURPOSE: We investigated efficacy and compliance related to percutaneous tibial nerve stimulation in patients treated for overactive bladder at a large, urban safety net hospital. MATERIALS AND METHODS: Consecutive patients who underwent percutaneous tibial nerve stimulation at Grady Memorial Hospital from May 2015 through January 2019 were included in our cohort and records were reviewed retrospectively. Primary outcomes of interest included self-reported urinary symptoms and episodes of urinary incontinence. Our secondary outcome of interest was patient compliance, defined as completion of 12 or more treatment sessions. Descriptive analysis and paired t-tests were performed. RESULTS: Of the 50 patients with a mean ± SD age of 59 ± 12 years 80% were black, 52% were male, 34% were uninsured and 54% subscribed to government insurance. Prior treatment included behavioral modification in 100% of cases, anticholinergics in 86% and mirabegron in 4%. Patients completed a mean of 10.7 ± 2.7 of the 12 planned weekly percutaneous tibial nerve stimulation treatments. Of the patients 70% completed all 12 weekly treatments and 77% of those who completed 12 treatments continued to maintenance treatment. After percutaneous tibial nerve stimulation treatment average symptoms improved across all metrics, including mean daytime frequency (from 11.0 to 6.6 episodes per day or -24.5%), nighttime frequency (from 4.8 to 2.5 episodes per night or -47.1%), urgency score (from 3.4 to 1.9 or -42.1%) and incontinence (from 1.6 to 0.4 episodes per day or -79.6%) (each p <0.001). A total of 43 patients (86%) reported symptom improvement. CONCLUSIONS: Percutaneous tibial nerve stimulation had favorable efficacy and compliance in a traditionally underserved patient population. This should be considered as a feasible modality to manage overactive bladder symptoms in patients in a similar demographic.

Diagnostic Performance and Interreader Agreement of a Standardized MR Imaging Approach in the Prediction of Small Renal Mass Histology.

Purpose To assess the diagnostic performance and interreader agreement of a standardized diagnostic algorithm in determining the histologic type of small (≤4 cm) renal masses (SRMs) with multiparametric magnetic resonance (MR) imaging. Materials and Methods This single-center retrospective HIPAA-compliant institutional review board-approved study included 103 patients with 109 SRMs resected between December 2011 and July 2015. The requirement for informed consent was waived. Presurgical renal MR images were reviewed by seven radiologists with diverse experience. Eleven MR imaging features were assessed, and a standardized diagnostic algorithm was used to determine the most likely histologic diagnosis, which was compared with histopathology results after surgery. Interreader variability was tested with the Cohen κ statistic. Regression models using MR imaging features were used to predict the histopathologic diagnosis with 5% significance level. Results Clear cell renal cell carcinoma (RCC) and papillary RCC were diagnosed, with sensitivities of 85% (47 of 55) and 80% (20 of 25), respectively, and specificities of 76% (41 of 54) and 94% (79 of 84), respectively. Interreader agreement was moderate to substantial (clear cell RCC, κ = 0.58; papillary RCC, κ = 0.73). Signal intensity (SI) of the lesion on T2-weighted MR images and degree of contrast enhancement (CE) during the corticomedullary phase were independent predictors of clear cell RCC (SI odds ratio [OR]: 3.19; 95% confidence interval [CI]: 1.4, 7.1; P = .003; CE OR, 4.45; 95% CI: 1.8, 10.8; P < .001) and papillary RCC (CE OR, 0.053; 95% CI: 0.02, 0.2; P < .001), and both had substantial interreader agreement (SI, κ = 0.69; CE, κ = 0.71). Poorer performance was observed for chromophobe histology, oncocytomas, and minimal fat angiomyolipomas, (sensitivity range, 14%-67%; specificity range, 97%-99%), with fair to moderate interreader agreement (κ range = 0.23-0.43). Segmental enhancement inversion was an independent predictor of oncocytomas (OR, 16.21; 95% CI: 1.0, 275.4; P = .049), with moderate interreader agreement (κ = 0.49). Conclusion The proposed standardized MR imaging-based diagnostic algorithm had diagnostic accuracy of 81% (88 of 109) and 91% (99 of 109) in the diagnosis of clear cell RCC and papillary RCC, respectively, while achieving moderate to substantial interreader agreement among seven radiologists. © RSNA, 2018 Online supplemental material is available for this article.

Effect of Differing Parameters on Irreversible Electroporation in a Porcine Model.

INTRODUCTION AND OBJECTIVE: Irreversible electroporation (IRE) is a new ablative technology to treat small renal masses. We evaluated differed ablation settings on lesion size and temperature changes in a porcine model. MATERIALS AND METHODS: After Institutional Animal Care and Use Committee approval, 36 laparoscopy-guided and 16 open ablations were performed on 13 domestic female pigs. Ablation parameters studied were voltage (1000 V/cm, 1500 V/cm, or 2000 V/cm), probe exposure (1.0 or 1.5 cm), and lesion size over time (survival) (0-, 7-, or 14 day). Temperature changes were monitored during open ablations with differed settings. Gross lesion size was measured, and histologic analysis with hematoxylin and eosin and nicotinamide adenine dinucleotide staining was performed. RESULTS: The 1000 V/cm ablations had no gross or histologic lesions. A factorial analysis of variance demonstrated that day (p = 0.56), exposure (p = 0.33), and voltage (p = 0.06) did not demonstrate statistical significance for affecting lesion size. For 1.0 cm probe exposure, 2000 V/cm did more closely approximate expected lesion size (p = 0.02) compared with 1500 V/cm. While significance was not seen for 1.5 cm probe exposure, 2000 V/cm often exceeded expected lesion volume. Only 1 of 4 temperature sensors, located adjacent to one of the IRE probes, noted a significant increase with increased voltage. However, all maximum temperatures remained less than 70°C. CONCLUSIONS: Variation in lesion volume was seen with different ablation settings in this porcine model. Maximal energy and probe exposure settings should be utilized to ensure full coverage of target volume/mass, potentially without concern for thermal injury to renal collecting system or nearby structures.

Three-Dimensional Printing of Surgical Clips: An In Vitro Pilot Study and Trial of Efficacy.

INTRODUCTION AND OBJECTIVE: Three-dimensional (3D) printing applications have increased over the past decade. Our objective was to test rapid prototyping of a 3D printed surgical clip for intraoperative use. MATERIALS AND METHODS: Our prototype was modeled after the 10 mm Weck® Hem-o-lok® polymer clip (Teleflex, Inc., Wayne, PA). A 3D computer-aided design model of the Hem-o-lok clip was reverse engineered using commercial microscopy and printing was done using an Objet Connex500 multijetting system (Stratasys, Eden Prairie, MN). The initial polymer was Objet VeroWhitePlus RGD835; the addition of Objet TangoBlackPlus FLX980 during the design process improved hinge flexibility. The 3D printed clips were then pressure tested on rubber Penrose tubing and compared in vitro versus commercial Hem-o-lok clips. RESULTS: Initial 3D printed clips were not functional as they split at the hinge upon closure of the clip jaws. Design changes were made to add Objet TangoBlackPlus FLX980 at the hinge to improve flexibility. Additional modifications were made to allow for clips to be compatible with the Hem-o-lok endoscopic clip applier. A total of 50 clips were tested. Fracture rate for the printed clips using a clip applier was 54% (n = 27), whereas none of the commercial Hem-o-lok clips broke upon closure. Of the 23 printed clips that closed, mean leak was at 20.7 κPa (range 4.8-42.7). In contrast, none of the commercial clips leaked, and fill continued until Penrose rupture at mean 46.2 κPa (44.8-47.6). CONCLUSIONS: This pilot study demonstrates feasibility of 3D printing functional surgical clips. However, the performance of our first generation clips is poor compared with commercial grade product. Refinement in printers and materials available may allow for customization of such printed surgical instruments that could be economically competitive to purchasing and stocking product.

Pain After Percutaneous Irreversible Electroporation of Renal Tumors Is Not Dependent on Tumor Location.

INTRODUCTION: Irreversible electroporation (IRE) is a non-thermal minimally invasive technique that is used to treat small renal masses (SRMs). Prior work has demonstrated greater narcotic requirements after radiofrequency ablation (RFA) for tumors that are closer to body-wall musculature. We hypothesized that pain after IRE is not dependent on tumor location due to the athermal mechanistic action. MATERIALS AND METHODS: A retrospective review of 50 consecutive percutaneous IRE and RFA cases was performed from 2013 to 2014. Eight patients were excluded from analysis due to incomplete anesthesia record and/or multiple ablations per session, leaving 21 patients in each group. Data collected included patient age, sex, body mass index, nephrometry score, shortest distance to the closest body-wall muscle, perioperative narcotic use, and patient-reported pain score. Pearson correlation test and multivariable linear regression were used to identify predictors of postoperative pain, with significance set at p = 0.05. RESULTS: There was no difference in the mean distance from tumor edge to the nearest body-wall muscle between IRE and RFA (2.6 cm vs 2.4 cm, p = 0.729, respectively). Total mean perioperative narcotic usage was 20.4 mg after IRE and 26.7 mg after RFA (p = 0.096). Mean postoperative pain score (scale 0-10) was slightly higher after RFA (4.3) compared with IRE (2.4), but this was not statistically significant (p = 0.088). Pearson correlation test identified tumor proximity to be significiantly associated with both pain score (p = 0.011) and postoperative narcotic use (p = 0.049) after RFA but not after IRE. On multivariable analysis, only tumor proximity to the body wall was significantly correlated to pain score (-1.4, p = 0.041) after RFA but was not found to be a factor for pain after IRE. CONCLUSIONS: Patients whose tumors lie close to their body-wall musculature do not have greater narcotic requirements or higher pain scores in the perioperative period after IRE. Percutaneous IRE may be preferred over RFA for SRMs that are close to the body wall to minimize pain.

Irreversible electroporation of small renal masses: suboptimal oncologic efficacy in an early series.

PURPOSE: To report on the first short-term oncologic outcomes of percutaneous irreversible electroporation for small renal masses. METHODS: Patients with cT1a renal masses treated with irreversible electroporation from April 2013 through December 2016 were reviewed. Small, low complexity tumors were generally selected for irreversible electroporation using the NanoKnife® System (Angiodynamics, Latham, NY, USA). Surveillance imaging was performed post-operatively, and survival analysis was completed using the Kaplan-Meier method. RESULTS: A total of 42 tumors in 41 patients underwent irreversible electroporation. Mean tumor size was 2.0 cm with a median R.E.N.A.L nephrometry score of 5. Twenty-nine patients (71%) were discharged the same day of the procedure and no major (Clavien grade II or higher) intraoperative or post-operative complications occurred. Initial treatment success rate was 93%; our three failures (7%) underwent salvage radiofrequency ablation. With a mean follow-up of 22 months, 2-year local recurrence-free survival was 83% for patients with biopsy confirmed renal cell carcinoma, 87% with biopsy confirmed or a history of renal cell carcinoma, and 92% for the intent-to-treat cohort. CONCLUSIONS: Although with low morbidity, in comparison to extirpation and conventional thermal ablation technologies, irreversible electroporation has suboptimal short-term local disease control results in this series of small, low complexity tumors. Larger series and longer follow-up will determine the durability of this modality.

Poor split renal function and age in adult patients with ureteropelvic junction obstruction do not impact functional outcomes of pyeloplasty.

INTRODUCTION: To examine if poor preoperative split renal function (SRF) and age influence pyeloplasty outcomes in adults with ureteropelvic junction obstruction (UPJO). MATERIALS AND METHODS: We retrospectively reviewed our pyeloplasty experience in adults with UPJO from 2004 to 2014. Patients with solitary kidneys or missing renal scans were excluded. Renal scans were performed at 6 weeks, 8 months, and 20-24 months postoperatively. Demographics, operative approaches, and pre and postoperative SRF and diuretic half-times (T1/2) were obtained. Patients were stratified by preoperative SRF (≤ or > 25%) and age. Cox regression analyses were performed to explore predictors for stability or improvement of SRF. RESULTS: A total of 139 patients met the study criteria: 15 and 124 with preoperative SRF ≤ 25% and > 25%, respectively. Median follow up was 11 months, 12.9% of patients experienced worsening, 67.6% stability, and 19.4% improvement in SRF at last follow up. Median change in SRF was similar between groups; however, patients with lower preoperative SRF more frequently experienced improvement or worsening of SRF (p = 0.045). Failure rates (need for additional surgery) were comparable (p = 1.000). No significant differences were observed in SRF dynamicity when stratified by age (p = 0.120). On univariate Cox analysis, older age was predictive of stability or improvement in SRF across the entire cohort (HR 1.013, p = 0.016), while preoperative SRF was not (HR 1.007, p = 0.429). CONCLUSIONS: Poor SRF (≤ 25%) and age were not associated with worse outcomes after pyeloplasty for UPJO. Our results suggest that older adults with UPJO and patients with poor ipsilateral SRF should not be excluded from pyeloplasty.

Posterior Urethral Suspension During Robot-Assisted Radical Prostatectomy Improves Early Urinary Control: A Prospective Cohort Study.

PURPOSE: Early urinary control is a major goal for patients undergoing robot-assisted radical prostatectomy (RARP). We report our technique of posterior urethral suspension (PUS) performed at the time of urethrovesical anastomosis. PATIENTS AND METHODS: We prospectively followed men with localized prostate cancer undergoing RARP by a single surgeon from August 2012 to October 2015. Patients before April 2014 underwent only bladder neck preservation (controls), while patients after April 2014 also underwent PUS. Patients were given a modified Expanded Prostate Cancer Index Composite questionnaire, along with questions depicting objective measures of urinary control (type of pad, number of pads, wetness of pad). Time points queried were preoperatively and postoperatively at weeks 1, 2, 4, and 12. Our primary outcome was pad-free survival. RESULTS: Questionnaire response rate was 52% (56/107) for controls and 43% (36/83) for PUS. There were no differences in baseline demographics, preoperative urinary control, intraoperative variables, or postoperative complications between groups. There were few subjective improvements in urinary control for PUS compared with controls. More notable, PUS patients had significantly improved objective measures of urinary control, including less protective incontinence products at 1 and 2 weeks after catheter removal (p < 0.03). They also wore fewer pads and had less leakage on each pad that lasted from week 1 to week 4 after catheter removal (p < 0.01). PUS patients had pad-free rates of 37%, 47%, 54%, and 60% compared with controls 15%, 18%, 24%, and 36%, at weeks 1, 2, 4, and 12 after catheter removal (p = 0.07). CONCLUSION: PUS may improve objective measures of early urinary control compared with controls. With no increase in operative time and no change in complication rates, further work in a randomized setting would provide additional weight to our findings.

Detecting positive surgical margins: utilisation of light-reflectance spectroscopy on ex vivo prostate specimens.

OBJECTIVE: To assess the efficacy of light-reflectance spectroscopy (LRS) to detect positive surgical margins (PSMs) on ex vivo radical prostatectomy (RP) specimens. MATERIALS AND METHODS: A prospective evaluation of ex vivo RP specimens using LRS was performed at a single institution from June 2013 to September 2014. LRS measurements were performed on selected sites on the prostate capsule, marked with ink, and correlated with pathological analysis. Significant features on LRS curves differentiating malignant tissue from benign tissue were determined using a forward sequential selection algorithm. A logistic regression model was built and randomised cross-validation was performed. The sensitivity, specificity, accuracy, negative predictive value (NPV), positive predictive value (PPV), and area under the receiver operating characteristic curve (AUC) for LRS predicting PSM were calculated. RESULTS: In all, 50 RP specimens were evaluated using LRS. The LRS sensitivity for Gleason score ≥7 PSMs was 91.3%, specificity 92.8%, accuracy 92.5%, PPV 73.2%, NPV 99.4%, and the AUC was 0.960. The LRS sensitivity for Gleason score ≥6 PSMs was 65.5%, specificity 88.1%, accuracy 83.3%, PPV 66.2%, NPV 90.7%, and the AUC was 0.858. CONCLUSIONS: LRS can reliably detect PSMs for Gleason score ≥7 prostate cancer in ex vivo RP specimens.

The Usefulness of Chest X-Rays for T1a Renal Cell Carcinoma Surveillance.

PURPOSE: The overall incidence of pulmonary metastasis of T1 renal cell carcinoma is low. We evaluated the usefulness of chest x-rays based on the current AUA (American Urological Association) guidelines and NCCN Guidelines® for T1a renal cell carcinoma surveillance. MATERIALS AND METHODS: Between 2006 and 2012, 258 patients with T1a renal cell carcinoma were treated with partial nephrectomy, radical nephrectomy or radio frequency ablation with surveillance followup at our institution. A retrospective chart review was performed to identify demographics, pathological findings and surveillance records. The primary outcome was the incidence of asymptomatic pulmonary recurrences diagnosed by chest x-ray in cases of T1a disease. Our secondary outcome was a comparison of diagnoses by treatment modality (partial nephrectomy, radical nephrectomy or radio frequency ablation). RESULTS: Pulmonary metastases developed in 3 of 258 patients (1.2%) but only 1 (0.4%) was diagnosed by standard chest x-ray surveillance. Median followup in the entire cohort was 36 months (range 6 to 152) and 193 of 258 patients (75%) had greater than 24 months of followup. A mean of 3.3 surveillance chest x-rays were completed per patient. When assessed by treatment type, there was no significant difference in the recurrence rate for partial nephrectomy (0 of 191 cases), radical nephrectomy (0 of 22) or radio frequency ablation (1 of 45 or 2.2%) (p = 0.09). CONCLUSIONS: Chest x-rays are a low yield diagnostic tool for detecting pulmonary metastasis in patients treated for T1a renal cel carcinoma. Treatment mode does not appear to influence the need for chest x-ray surveillance.

Likelihood of Incomplete Kidney Tumor Ablation with Radio Frequency Energy: Degree of Enhancement Matters.

PURPOSE: Larger size and clear cell histopathology are associated with worse outcomes for malignant renal tumors treated with radio frequency ablation. We hypothesize that greater tumor enhancement may be a risk factor for radio frequency ablation failure due to increased vascularity. MATERIALS AND METHODS: A retrospective review of patients who underwent radio frequency ablation for renal tumors with contrast enhanced imaging available was performed. The change in Hounsfield units (HU) of the tumor from the noncontrast phase to the contrast enhanced arterial phase was calculated. Radio frequency ablation failure rates for biopsy confirmed malignant tumors were compared using the chi-squared test. Multivariate logistic analysis was performed to assess predictive variables for radio frequency ablation failure. Disease-free survival was calculated using Kaplan-Meier analysis. RESULTS: A total of 99 patients with biopsy confirmed malignant renal tumors and contrast enhanced imaging were identified. The incomplete ablation rate was significantly lower for tumors with enhancement less than 60 vs 60 HU or greater (0.0% vs 14.6%, p=0.005). On multivariate logistic regression analysis tumor enhancement 60 HU or greater (OR 1.14, p=0.008) remained a significant predictor of incomplete initial ablation. The 5-year disease-free survival for size less than 3 cm was 100% vs 69.2% for size 3 cm or greater (p <0.01), while 5-year disease-free survival for HU change less than 60 was 100% vs 92.4% for HU change 60 or greater (p=0.24). CONCLUSIONS: Biopsy confirmed malignant renal tumors, which exhibit a change in enhancement of 60 HU or greater, experience a higher rate of incomplete initial tumor ablation than tumors with enhancement less than 60 HU. Size 3 cm or greater portends worse 5-year disease-free survival after radio frequency ablation. The degree of enhancement should be considered when counseling patients before radio frequency ablation.

Light Reflectance Spectroscopy to Detect Positive Surgical Margins on Prostate Cancer Specimens.

PURPOSE: Intraoperative frozen section analysis is not routinely performed to determine positive surgical margins at radical prostatectomy due to time requirements and unproven clinical usefulness. Light reflectance spectroscopy, which measures light intensity reflected or backscattered from tissues, can be applied to differentiate malignant from benign tissue. We used a novel light reflectance spectroscopy probe to evaluate positive surgical margins on ex vivo radical prostatectomy specimens and correlate its findings with pathological examination. MATERIALS AND METHODS: Patients with intermediate to high risk disease undergoing radical prostatectomy were enrolled. Light reflectance spectroscopy was performed on suspected malignant and benign prostate capsule immediately following organ extraction. Each light reflectance spectroscopy at 530 to 830 nm was analyzed and correlated with pathological results. A regression model and forward sequential selection algorithm were developed for optimal feature selection. Eighty percent of light reflectance spectroscopy data were selected to train a logistic regression model, which was evaluated by the remaining 20% data. This was repeated 5 times to calculate averaged sensitivity, specificity and accuracy. RESULTS: Light reflectance spectroscopy analysis was performed on 17 ex vivo prostate specimens, on which a total of 11 histologically positive and 22 negative surgical margins were measured. Two select features from 700 to 830 nm were identified as unique to malignant tissue. Cross-validation when performing the predictive model showed that the optical probe predicted positive surgical margins with 85% sensitivity, 86% specificity, 86% accuracy and an AUC of 0.95. CONCLUSIONS: Light reflectance spectroscopy can identify positive surgical margins accurately in fresh ex vivo radical prostatectomy specimens. Further study is required to determine whether such analysis may be used in real time to improve surgical decision making and decrease positive surgical margin rates.

Oncologic Efficacy of Radio Frequency Ablation for Small Renal Masses: Clear Cell vs Papillary Subtype.

PURPOSE: Current radio frequency ablation series do not distinguish renal cell carcinoma subtypes when reporting oncologic efficacy. Papillary neoplasms may be more amenable to radio frequency ablation than clear cell carcinoma because they are less vascular, which may limit heat energy loss. We report the long-term outcomes of patients treated with radio frequency ablation for small renal masses by renal cell carcinoma subtype. MATERIALS AND METHODS: The records of patients undergoing radio frequency ablation for small renal masses (cT1a) at 2 institutions from March 2007 to July 2012 were retrospectively reviewed. Patients were included in analysis if they had biopsy confirmed clear cell or papillary renal cell carcinoma histology. Patients had at least 1 contrast enhanced cross-sectional image following radio frequency ablation. Demographic data between tumor subtypes were compared using the paired t-test. Oncologic outcomes were determined by Kaplan-Meier survival analysis and survivor curves were compared with the log rank test. RESULTS: A total of 229 patients met study inclusion criteria. There were 181 clear cell tumors and 48 papillary tumors. Median followup was 33.2 months. There was no difference between tumor groups based on patient age, tumor size or grade, or months of followup. Five-year disease-free survival was 89.7% for clear cell tumors and 100% for papillary tumors (p = 0.041). There was no significant difference in overall survival (88.4% vs 89.6%, p = 0.764). CONCLUSIONS: Radio frequency ablation outcomes seem to be determined in part by renal cell carcinoma subtype with clear cell renal tumors having less favorable outcomes. We hypothesize that this is due to differences in tumor vascularity. Our experience suggests that future tumor ablation studies should consider reporting outcomes based on tumor cell types.

The role of neuromodulation in patients with neurogenic overactive bladder.

To review the treatment options for patients with neurogenic overactive bladder (OAB), specifically the use of sacral neuromodulation (SNM). A search was performed on the available literature on SNM and lower urinary tract dysfunction. Based on published studies available and also on personal experience, the treatment options for neurogenic OAB are reviewed, and specifically, the role for SNM in these patients is discussed. SNM is FDA-approved for patients with urge incontinence, urgency/frequency, and non-obstructive urinary retention. It involves stimulation of the third sacral nerve with an electrode implanted in the sacral foramen and connected to a pulse generator. The procedure is minimally invasive and is effective in about 70 % of patients who have a permanent system. The original trials leading to the approval of SNM excluded patients with neurogenic disease, as it was felt that intact spinal pathways were necessary for neuromodulation to occur. However, similar success rates have been observed in patients with neurogenic OAB. Special considerations for SNM use in patients with neurogenic OAB include recognizing that it is incompatible for patients who will need MRI's due to their progressive neurologic disease. Many treatment options are available for patients with neurogenic OAB. First-line approaches remain conservative with lifestyle changes and anticholinergic medications. SNM has been used successfully in this patient population with good results, though larger randomized trials are lacking.

New therapies for castrate-resistant prostate cancer.

INTRODUCTION: Prostate cancer is the second leading cause of cancer death in men in the USA, and most of these deaths will occur as a result of castrate-resistant prostate cancer (CRPC) that has progressed despite androgen deprivation therapy. There has been better understanding of castration resistance and molecular mechanisms of prostate cancer progression recently, leading to new treatment strategies. AREAS COVERED: This review focuses on emerging and new therapies for castrate-resistant prostate cancer, including hormonal therapy, immunotherapy and cytotoxic agents. EXPERT OPINION: New treatment strategies have been developed in recent years and, with improved understanding of advanced CRPC, additional targeted treatments are expected in the near future. Further cost effectiveness research of these treatments is warranted before dissemination of these promising agents.