Factors Associated with Ureteral Stent Failure in Patients with Malignant Ureteral Obstruction.

Introduction: Management of malignant ureteral obstruction (MUO) with ureteral stents remains a clinical challenge, often involving frequent stent exchanges attributable to stent failure or other urological complications. We report our institutional experience with ureteral stents for management of MUO, including analysis of clinical factors associated with stent failure. Methods: We performed a retrospective review of patients treated with indwelling ureteral stents for MUO in nonurothelial malignancies at our tertiary-care institution between 2008 and 2019. Univariate Cox proportional hazards analysis was performed to identify clinical variables associated with stent failure and stent-related complications. Stent failure was defined as need for unplanned stent exchange, placement of percutaneous nephrostomy (PCN), or tandem stents. Results: In our cohort of 78 patients, the median (range) number of stent exchanges was 2 (0-17) during a total stent dwell time of 4.3 (0.1-40.3) months. Thirty-four patients (43.6%) developed a culture-proven urinary tract infection (UTI) during stent dwell time. Thirty-five patients (44.8%) had stent failure. Twenty-two patients (28.2%) underwent unplanned stent exchanges, 23 (29.5%) required PCN after initial stent placement, and 6 (7.7%) required tandem stents. Ten (28.6%) patients with stent failure were treated with upsized stents, which led to resolution in seven patients. Stent failure occurred with 20/44 (45.4%) Percuflex™, 15/27 (55.6%) polyurethane, and 2/3 (66.7%) metal stents. In patients with ≥2 exchanges (N = 45), median time between exchanges was 4.1 (2.0-14.8) months. Bilateral stenting and history of radiation predicted UTI development. Median overall patient survival after initial stent placement was 19.9 months (95% CI 16.5-37.9 months). Conclusions: Ureteral stent failure poses a significant medical burden to patients with MUO. Better methods to minimize stent-related issues and improve patient quality of life are needed. Using a shared decision-making approach, clinicians and patients should consider PCN or tandem stents early in the management of MUO.

Role of the androgen, estrogen, and progesterone receptors in adherent perinephric fat in robotic partial nephrectomy.

To determine whether androgen, estrogen, and/or progesterone signaling play a role in the pathophysiology of adherent perinephric fat (APF). We prospectively recruited patients undergoing robotic assisted partial nephrectomy during 2015-2017. The operating surgeon documented the presence or absence of APF. For those with clear cell renal cell carcinoma (ccRCC), representative sections of tumor and perinephric fat were immunohistochemically stained with monoclonal antibody to estrogen α, progesterone, and androgen receptors. Patient characteristics, operative data, and hormone receptor presence were compared between those with and without APF. Of 51 patients total, 18 (35.3%) and 33 (64.7%) patients did and did not have APF, respectively. APF was associated with history of diabetes mellitus (61.1% vs 24.2%, p = 0.009) and larger tumors (4.0 cm vs 3.0 cm, p = 0.017) but not with age, gender, BMI, Charleston comorbidity index, smoking, or preoperative estimated glomerular filtration rate. APF was not significantly associated with length of operation, positive margins, or 30-day postoperative complications but incurred higher estimated blood loss (236.5 mL vs 209.2 mL, p = 0.049). Thirty-two had ccRCC and completed hormone receptor staining. The majority of tumors and perinephric fat were negative for estrogen and progesterone while positive for androgen receptor expression. There was no difference in hormone receptor expression in either tumor or perinephric fat when classified by presence or absence of APF (p > 0.05). APF is more commonly present in patients with diabetes or larger tumors but was not associated with differential sex hormone receptor expression in ccRCC.

Contemporary Pure Laparoscopic vs Robot-Assisted Laparoscopic Radical Nephrectomy: Is the Transition Worth It?

Introduction: The proportion of robotic procedures continues to rise. The literature reinforces that robotic procedures take longer and are often more costly. We compared cost and perioperative outcomes of laparoscopic radical nephrectomy (LRN) and robot-assisted radical nephrectomy (RARN) at our high-volume center. Materials and Methods: We retrospectively reviewed our 2012-2015 data repository for patients undergoing RARN and LRN for a renal mass. Perioperative and oncologic outcomes were compared. We performed a multivariate analysis of operative time, estimated blood loss, length of stay (LOS), and overall and major 90-day complication rates while controlling for demographic data, Charlson comorbidity index (CCI), tumor size, and surgeon factors. We compared fixed, variable, and distinct procedural costs. Results: We identified 99 LRN and 95 RARN cases. There was no difference in demographic data, tumor size, preoperative renal function, and malignant histology. LRN patients had more comorbidities (49.5% vs 27.3% CCI 2+, p = 0.018). The mean preoperative glomerular filtration rate was higher in the robotic cohort (84.8 vs 75.1, p = 0.48). Mean operative time was 32.7 minutes longer (p = 0.002) and estimated blood loss 145 mL higher (p = 0.007) for the RARN cohort. There was no difference in mean LOS. Major and all 90-day complication rates were no different. The mean procedural cost for RARN was higher by $464 when controlling for operative time (p < 0.001). Fixed costs were not statistically different. Variable costs for RARN were estimated to be $2,310 higher (p = 0.045). Conclusions: Even with cost-conscious, experienced renal surgeons, RARN is associated with a longer procedure, higher supply costs, and higher hospitalization costs. There was no difference in positive surgical margin and complications. There were fewer 30-day readmissions for the RARN cohort, which may represent under-recognized cost savings. With fewer LRN cases in the United States each year, discussion to address cost is warranted. Without better outcomes for robotic surgery, a change in reimbursement to cover costs is unlikely to happen.

Ex Vivo Porcine Model for Robot-Assisted Partial Nephrectomy Simulation at a High-Volume Tertiary Center: Resident Perception and Validation Assessment Using the Global Evaluative Assessment of Robotic Skills Tool.

Introduction: With increased demands on surgeon productivity and outcomes, residency robotics training increasingly relies on simulations. The objective of this study is to assess the validity and effectiveness of an ex vivo porcine training model as a useful tool to improve surgical skill and confidence with robot-assisted partial nephrectomy (RAPN) among urology residents. Methods: A 2.5 cm circular area of ex vivo porcine kidneys was marked as the area of the tumor. Tumor excision and renorrhaphy was performed by trainees using a da Vinci Si robot. All residents ranging from postgraduate year (PGY) 2 to 5 participated in four training sessions during the 2017 to 2018 academic year. Each session was videorecorded and scored using the global evaluative assessment of robotic skills (GEARS) by faculty members. Results: Twelve residents completed the program. Initial mean GEARS score was 16.7 and improved by +1.4 with each subsequent session (p = 0.008). Initial mean excision, renorrhaphy, and total times were 8.2, 13.9, and 22.1 minutes, which improved by 1.6, 2.0, and 3.6 minutes, respectively (all p < 0.001). Residents' confidence at performing RAPN and robotic surgery increased after completing the courses (p = 0.012 and p < 0.001, respectively). Overall, residents rated that this program has greatly contributed to their skill (4/5) and confidence (4.1/5) in robotic surgery. Conclusions: An ex vivo porcine simulation model for RAPN and robotic surgery provides measurable improvement in GEARS score and reduction in procedural time, although significant differences for all PGY levels need to be confirmed with larger study participation. Adoption of this simulation in a urology residency curriculum may improve residents' skill and confidence in robotic surgery.

Positive Surgical Margins After Robot-Assisted Partial Nephrectomy Predict Long-Term Oncologic Outcomes for Clinically Localized Renal Masses.

Introduction: For patients with clinically localized renal masses, positive surgical margins (PSMs) after robotic partial nephrectomy (RPN) have been associated with a higher risk of disease recurrence, although some studies have challenged this conclusion. Owing to inconsistent reports and a lack of long-term robotic data, the clinical impact of PSM after RPN remains uncertain. We evaluate long-term (>6 years) survival outcomes after RPN in patients with clinically localized disease with respect to surgical margin status. Methods: We conducted a retrospective review of patients who underwent RPN for clinically localized renal masses from June 2007 to December 2012 at Washington University School of Medicine. Disease recurrence and overall survival (OS) were stratified on the presence or absence of PSM. The cohort was analyzed to identify patient- and tumor-specific characteristics associated with PSM. Results: We identified 374 RPNs performed from 2007 to 2012 with a mean follow-up time of 77.7 months (SD 32.2 months). PSM was identified in 12 (3.2%) patients. Patients with PSM were at 14-fold increased risk for recurrence with no difference in OS (p < 0.001, p = 0.130, respectively). Patients with PSM had higher incidence of chronic obstructive pulmonary disease (COPD) (25% vs 6.4%) and greater blood loss (425 mL vs 203 mL). Conclusion: With an extended follow-up period of 77 months after RPN, we found that PSM substantially increased the risk of recurrence without impacting OS. Our finding that PSM may occur more frequently in older patients with COPD must be confirmed in larger studies.

Post-chemotherapy Laparoscopic Retroperitoneal Lymph Node Dissection for Mixed Malignant Germ Cell Testicular Tumors.

INTRODUCTION: Retroperitoneal lymph node dissection (RPLND) is performed to treat residual disease following chemotherapy for stage II and III testicular cancer. Significant morbidity can be associated with open RPLND. As such, laparoscopic techniques have been demonstrated to be safe and effective in select cases. Outcomes following post-chemotherapy laparoscopic RPLND for mixed malignant germ cell testicular tumors (MMGCT) are limited in the literature. PATIENTS AND METHODS: We performed a retrospective chart review for patients who underwent laparoscopic RPLND at our institution for MMGCT from May 2006 to October 2016. Patient clinical data and perioperative and oncologic outcomes were recorded. RESULTS: Twenty-three patients underwent post-chemotherapy laparoscopic RPLND. Thirty-five percent (8/23) underwent bilateral template dissection, whereas 65% (15/23) underwent a modified unilateral template dissection. Robotic assistance was utilized in 22% (5/23) of cases. Bilateral template was inferior to unilateral template RPLND in operative time, estimated blood loss, open conversion rate, length of hospital stay, and complication rate. The mean follow-up was 35.1 months and 43.3 months for the bilateral and unilateral template groups, respectively. The mean lymph node yield and recurrence rate were similar between the 2 cohorts. One recurrence of mature teratoma was noted 67 months after unilateral laparoscopic RPLND. CONCLUSIONS: In select patients, laparoscopic RPLND for stage II and III MMGCT is safe and effective in the post-chemotherapy setting. Bilateral template laparoscopic RPLND was associated with inferior perioperative outcomes, but similar oncologic outcomes compared with unilateral template. Patients requiring bilateral template RPLND should be considered for an open approach.

Ten-Year Experience with Percutaneous Cryoablation of Renal Tumors: Tumor Size Predicts Disease Progression.

Introduction: Percutaneous cryoablation (PCA) has emerged as an alternative to extirpative management of small renal masses (SRMs) in select patients, with a reduced risk of perioperative complications. Although disease recurrence is thought to occur in the early postoperative period, limited data on long-term oncologic outcomes have been published. We reviewed our 10-year experience with PCA for SRMs and assessed predictors of disease progression. Materials and Methods: We reviewed our prospectively maintained database of patients who underwent renal PCA from March 2005 to December 2015 (n = 308). Baseline patient and tumor variables were recorded, and postoperative cross-sectional imaging was examined for evidence of disease recurrence. Disease progression was defined as the presence of local recurrence or new lymphadenopathy/metastasis. Results: Mean patient age was 67.2 ± 11 years, mean tumor size was 2.7 ± 1.3 cm, and mean nephrometry score was 6.8 ± 1.7. At mean follow-up of 38 months, local recurrence and new lymphadenopathy/metastasis occurred in 10.1% (31/308) and 6.2% (19/308) of patients, respectively. Excluding patients with a solitary kidney and/or von Hippel-Lindau, local recurrence and new lymphadenopathy/metastasis occurred in 8.6% (23/268) and 1.9% (5/268) of cases, respectively. Kaplan-Meier estimated disease-free survival was 92.5% at 1 year, 89.3% at 2 years, and 86.7% at 3 years post-PCA. Increasing tumor size was a significant predictor of disease progression (hazard ratio 1.32 per 1-cm increase in size, p = 0.001). Conclusions: PCA is a viable treatment option for patients with SRMs. Increasing tumor size is a significant predictor of disease progression following PCA.

Comparing Off-clamp and On-clamp Robot-assisted Partial Nephrectomy: A Prospective Randomized Trial.

OBJECTIVE: To determine whether performing robot-assisted partial nephrectomy without warm ischemia "off-clamp" results in favorable postoperative renal functional outcomes compared with the on-clamp method. METHODS: We conducted a prospective trial of 80 patients who underwent robot-assisted partial nephrectomy. They were randomized in a 1:1 ratio to undergo the procedure with renal artery clamping or without clamping. The groups were compared across demographics, operative information, perioperative outcomes, and postoperative renal function. We assessed renal function by estimated glomerular filtration rate and renal scintigraphy both preoperatively and at 3 months postoperatively. RESULTS: Patients in the on-clamp and off-clamp groups were similar in age, gender, body mass index, comorbidities, clinical tumor size, nephrometry score, and laterality. Off-clamp procedures were lengthier at an average 178.0 minutes vs 156.0 minutes for on-clamp (P = .011). Estimated blood loss, rates of pelvicalyceal repair, postoperative complications, and positive margins were not different. At a median 3-month follow-up, no significant differences were seen in change in postoperative estimated glomerular filtration rate or percent split renal function between both groups. CONCLUSION: In this prospective study, off-clamp robot-assisted partial nephrectomy resulted in similar perioperative outcomes compared with the on-clamp technique. No benefit was demonstrated in the preservation of renal function. Urologists may safely employ either an on-clamp or off-clamp strategy depending on surgeon preference and patient-specific factors including baseline renal insufficiency, multiple masses, or solitary kidney.

Unplanned 30-Day Encounters After Ureterorenoscopy for Urolithiasis.

OBJECTIVE: To identify avoidable predictors of postureteroscopy (URS) unplanned encounters and to minimize 30-day encounters. MATERIALS AND METHODS: We performed retrospective chart review and telephone surveys on patients who underwent URS for urolithiasis between January and June 2016. Univariate and multivariable analyses evaluated for potential predictors of unplanned encounters. RESULTS: Of 157 patients, there were 44 (28.0%) unplanned patient-initiated clinical phone calls, 23 (14.6%) emergency department (ED) visits, and 8 (5.1%) readmissions, with pain being the most common complaint during the encounters. Factors associated with a higher rate of phone calls include first-time stone procedure (36.6% vs 20.9%, p = 0.029), outpatient status (30.3% vs 0%, p = 0.021), intraoperative stent placement (31.2% vs 0%, p = 0.006), and stent removal at home (58.8% vs 28.8%, p = 0.014). Factors associated with increased rate of ED visits were first-time stone procedure (22.5% vs 8.1%, p = 0.011) and ureteral access sheath (UAS) usage (29.6% vs 11.8%, p = 0.018). Factors associated with a higher rate of readmissions were lower body mass index (23.9 vs 29.7, p = 0.013), bilateral procedure (20.0% vs 2.9%, p = 0.010), and UAS usage (14.8% vs 3.1%, p = 0.032). Stone burden, operative time, Charlson comorbidity index, and preoperative urinary tract infection were not significantly associated with postoperative encounters. CONCLUSIONS: Pain, first-time stone treatment, presence of a ureteral stent, outpatient status, bilateral procedures, and UAS usage were common reasons for postoperative encounters after URS. Appropriate perioperative patient education and counseling and adequate pain management may minimize these encounters and improve treatment quality and patient satisfaction.

Development and Validity of a Silicone Renal Tumor Model for Robotic Partial Nephrectomy Training.

OBJECTIVE: To provide a training tool to address the technical challenges of robot-assisted laparoscopic partial nephrectomy, we created silicone renal tumor models using 3-dimensional printed molds of a patient's kidney with a mass. In this study, we assessed the face, content, and construct validity of these models. MATERIALS AND METHODS: Surgeons of different training levels completed 4 simulations on silicone renal tumor models. Participants were surveyed on the usefulness and realism of the model as a training tool. Performance was measured using operation-specific metrics, self-reported operative demands (NASA Task Load Index [NASA TLX]), and blinded expert assessment (Global Evaluative Assessment of Robotic Surgeons [GEARS]). RESULTS: Twenty-four participants included attending urologists, endourology fellows, urology residents, and medical students. Post-training surveys of expert participants yielded mean results of 79.2 on the realism of the model's overall feel and 90.2 on the model's overall usefulness for training. Renal artery clamp times and GEARS scores were significantly better in surgeons further in training (P ≤.005 and P ≤.025). Renal artery clamp times, preserved renal parenchyma, positive margins, NASA TLX, and GEARS scores were all found to improve across trials (P <.001, P = .025, P = .024, P ≤.020, and P ≤.006, respectively). CONCLUSION: Face, content, and construct validity were demonstrated in the use of a silicone renal tumor model in a cohort of surgeons of different training levels. Expert participants deemed the model useful and realistic. Surgeons of higher training levels performed better than less experienced surgeons in various study metrics, and improvements within individuals were observed over sequential trials. Future studies should aim to assess model predictive validity, namely, the association between model performance improvements and improvements in live surgery.

Off-clamp robot-assisted partial nephrectomy does not benefit short-term renal function: a matched cohort analysis.

In the interest of renal functional preservation, partial nephrectomy has supplanted radical nephrectomy as the preferred treatment for T1 renal masses. This procedure usually involves the induction of renal warm ischemia by clamping the hilar vessels prior to tumor excision. Performing robot-assisted partial nephrectomy (RAPN) "off-clamp" can theoretically prevent renal functional loss associated with warm ischemia. We describe our institutional experience and compare perioperative and renal functional outcomes using a propensity score matched cohort. We conducted a retrospective comparison from a prospectively maintained database of all patients who underwent RAPN from 2009 to 2015. Of those patients, 143 underwent off-clamp RAPN. Fifty off-clamp RAPN patients were propensity score matched with fifty clamped RAPN patients based on renal function, tumor size, and R.E.N.A.L. nephrometry score. The cohorts were compared across demographics, operative information, perioperative outcomes, and renal functional outcomes. For all off-clamp RAPN patients, mean nephrometry score was 7.1, mean estimated blood loss (EBL) was 236.9 mL, perioperative complication rate was 7.7%, and mean decrease in estimated glomerular filtration rate (eGFR) was 7.1% at a median follow-up of 9.2 months. In the propensity score matched cohorts, off-clamp RAPN resulted in a shorter mean operative time (172.0 versus 196.0 min, p = 0.025) and a lower mean EBL (179.7 versus 283.2 mL, p = 0.046). A lower complication rate of 6.0% in the off-clamp group compared with 20.0% in the clamped group approached significance (p = 0.071). Mean preoperative eGFR was similar in both cohorts. Importantly, there was no significant difference in decrease in eGFR between the clamped cohort (9.8%) and off-clamp cohort (11.9%) at a median follow-up of 9.0 months (p = 0.620). Off-clamp RAPN did not result in improved renal functional preservation in our experience. Surprisingly, the off-clamp cohort experienced lower intraoperative blood loss, shorter operative times, and fewer complications.

Orgasmic Function after Radical Prostatectomy.

PURPOSE: We examined postprostatectomy orgasmic function and assessed for potential predictors. MATERIALS AND METHODS: Between 2005 and 2013, 499 men underwent radical prostatectomy and completed quality of life questionnaires prospectively before surgery and at regular postoperative intervals. We used mixed effects logistic regression models to evaluate average differences in followup measures and interactions with time. RESULTS: At a median followup of 36 months orgasmic function was worse, stable or improved in 300 (60.1%), 152 (30.5%) and 47 men (9.4%), respectively. Orgasmic function recovery plateaued at 15 to 21 months. High postoperative orgasmic function was positively associated with younger age (50 years or younger vs 51 to 60 OR 3.40, 95% CI 1.56-7.41), nerve sparing (bilateral OR 7.11, 95% CI 2.55-19.77, modified 4.34, 95% CI 1.38-13.58 and unilateral OR 3.93, 95% CI 1.17-13.16), erectile function (OR 4.67, 95% CI 3.32-6.57) and sexual desire (OR 5.51, 95% CI 3.95-7.68) but negatively associated with lower urinary tract symptoms (OR 0.58, 95% CI 0.41-0.82) and urinary incontinence (OR 0.38, 95% CI 0.25-0.56). Although robotic status did not influence orgasmic function in the overall cohort, it was associated with faster recovery on subgroup analysis of 356 patients with long followup. On another subgroup analysis of 235 men with long followup and poor erectile function the association of high preoperative orgasmic function and bilateral nerve sparing with high orgasmic function persisted, suggesting an independent effect on orgasmic function apart from that on erectile function. CONCLUSIONS: Orgasmic function recovery after radical prostatectomy is a lengthy process. Predictors of orgasmic function include preoperative orgasmic function, age, nerve sparing status, erectile function, sexual desire and urinary control and function.

Enterocystoplasty 30-day outcomes from National Surgical Quality Improvement Program Pediatric 2012.

INTRODUCTION: Enterocystoplasty is an important procedure in the management of children with difficult neurogenic bladder. We report on short-term complications as captured by National Surgical Quality Improvement Program (NSQIP) Pediatric. METHODS: We analyzed NSQIP Pediatric 30-day perioperative data on 114 patients who underwent enterocystoplasty in 2012 and compared those with and without complications. RESULTS: Neurogenic bladder was the most common diagnosis. The proportion of the children who underwent two or more procedures was 71.9%, in addition to enterocystoplasty, most commonly appendicovesicostomy. Median length of hospital stay was 8 days (mean 9.7 days, range 2 to 46 days). Thirty-day complication rate was 33.3%, and the most common complications were urinary tract infections (9.6%), wound complications (8.7%), blood transfusions (6.1%), and sepsis (3.5%). Reoperation rate and readmission rate were 9.6% and 13.2%, respectively. No statistically significant differences in perioperative characteristics were found between children with and without postoperative complications. Addition of appendicovesicostomy or bladder neck continence procedures was not associated with significantly increased complications. CONCLUSION: Enterocystoplasty is associated with significant perioperative morbidity, and reasonable expectations should be set during preoperative counseling.