Thulium fiber laser vs Ho:YAG in RIRS: a prospective randomized clinical trial assessing the efficacy of lasers and different fiber diameters (150 µm and 200 µm).

INTRODUCTION: The aims of the study: (1) to compare the Super Pulse Thulium Fiber Laser (SP TFL) and the holmium: yttrium-aluminium-garnet (Ho:YAG) lasers in retrograde intrarenal surgery (RIRS); (2) to compare the efficacy of SP TFL laser fibers of different diameters (150 µm and 200 µm). METHODS: A prospective randomized single-blinded trial was conducted. Patients with stones from 10 to 20 mm were randomly assigned RIRS in three groups: (1) SP TFL (NTO IRE-Polus, Russia) with fiber diameter of 150 µm; (2) SP TFL with 200-µm fiber; and (3) Ho:YAG (Lumenis, USA) with 200-µm fiber. RESULTS: Ninety-six patients with kidney stones were randomized to undergo RIRS with SP TFL using a 150-µm fiber (34 patients) and a 200-µm fiber (32 patients) and RIRS with Ho:YAG (30 patients). The median laser on time (LOT) in the 200-µm SP TFL group was 9.2 (6.2-14.6) min, in 150-µm SP TFL-11.4 (7.7-14.9) min (p = 0.390), in Ho:YAG-14.1 (10.8-18.1) min (p = 0.021). The total energy consumed in 200-µm SP TFL was 8.4 (5.8-15.2) kJ; 150-µm SP TFL - 10.8 (7.3-13.5) kJ (p = 0.626) and in Ho:YAG-15.2 (11.1-25.3) kJ (p = 0.005). CONCLUSIONS: Irrespective of the density, RIRS with SP TFL laser has proven to be both a safe and effective procedure. Whilst the introduction of smaller fibers may have the potential to reduce the duration of surgery, SP TFL results in a reduction in the LOT and total energy for stone ablation in RIRS compared with Ho:YAG.

Durability of Response to Primary Chemoablation of Low-Grade Upper Tract Urothelial Carcinoma Using UGN-101, a Mitomycin-Containing Reverse Thermal Gel: OLYMPUS Trial Final Report.

PURPOSE: Our goal was to evaluate long-term safety and durability of response to UGN-101, a mitomycin-containing reverse thermal gel, as primary chemoablative treatment for low-grade upper tract urothelial carcinoma. MATERIALS AND METHODS: In this open-label, single-arm, multicenter, phase 3 trial (NCT02793128), patients ≥18 years of age with primary or recurrent biopsy-proven low-grade upper tract urothelial carcinoma received 6 once-weekly instillations of UGN-101 via retrograde catheter to the renal pelvis and calyces. Those with complete response (defined as negative ureteroscopic evaluation, negative cytology and negative for-cause biopsy) 4-6 weeks after the last instillation were eligible for up to 11 monthly maintenance instillations and were followed for ≥12 months with quarterly evaluation of response durability. Durability of complete response was determined by ureteroscopic evaluation; duration of response was estimated by the Kaplan-Meier method. Treatment-emergent adverse events (TEAEs) were monitored. RESULTS: Of 71 patients who initiated treatment, 41 (58%) had complete response to induction therapy and consented to long-term followup; 23/41 patients (56%) remained in complete response after 12 months (95% CI 40, 72), comprising 6/12 (50%) who did not receive any maintenance instillations and 17/29 (59%) who received ≥1 maintenance instillation. Kaplan-Meier analysis of durability was estimated as 82% (95% CI 66, 91) at 12 months. Ureteric stenosis was the most frequently reported TEAE (31/71, 44%); an increasing number of instillations appeared to be associated with increased incidence of urinary TEAEs. CONCLUSIONS: Durability of response to UGN-101 with or without maintenance treatment is clinically meaningful, offering a kidney-sparing therapeutic alternative for patients with low-grade disease.

Primary chemoablation of low-grade upper tract urothelial carcinoma using UGN-101, a mitomycin-containing reverse thermal gel (OLYMPUS): an open-label, single-arm, phase 3 trial.

BACKGROUND: Most patients with low-grade upper tract urothelial cancer are treated by radical nephroureterectomy. We aimed to assess the safety and activity of a non-surgical treatment using instillation of UGN-101, a mitomycin-containing reverse thermal gel. METHODS: In this open-label, single-arm, phase 3 trial, participants were recruited from 24 academic sites in the USA and Israel. Patients (aged ≥18 years) with primary or recurrent biopsy-proven, low-grade upper tract urothelial cancer (measuring 5-15 mm in maximum diameter) and an Eastern Cooperative Oncology Group performance status score of less than 3 (Karnofsky Performance Status score >40) were registered to receive six instillations of once-weekly UGN-101 (mitomycin 4 mg per mL; dosed according to volume of patient's renal pelvis and calyces, maximum 60 mg per instillation) via retrograde catheter to the renal pelvis and calyces. All patients had a planned primary disease evaluation 4-6 weeks after the completion of initial therapy, in which the primary outcome of complete response was assessed, defined as negative 3-month ureteroscopic evaluation, negative cytology, and negative for-cause biopsy. Activity (complete response, expected to occur in >15% of patients) and safety were assessed by the investigator in all patients who received at least one dose of UGN-101. Data presented are from the data cutoff on May 22, 2019. This study is registered with ClinicalTrials.gov, NCT02793128. FINDINGS: Between April 6, 2017, and Nov 26, 2018, 71 (96%) of 74 enrolled patients received at least one dose of UGN-101. 42 (59%, 95% CI 47-71; p<0·0001) patients had a complete response at the primary disease evaluation visit. The median follow-up for patients with a complete response was 11·0 months (IQR 5·1-12·4). The most frequently reported all-cause adverse events were ureteric stenosis in 31 (44%) of 71 patients, urinary tract infection in 23 (32%), haematuria in 22 (31%), flank pain in 21 (30%), and nausea in 17 (24%). 19 (27%) of 71 patients had study drug-related or procedure-related serious adverse events. No deaths were regarded as related to treatment. INTERPRETATION: Primary chemoablation of low-grade upper tract urothelial cancer with intracavitary UGN-101 results in clinically significant disease eradication and might offer a kidney-sparing treatment alternative for these patients. FUNDING: UroGen Pharma.

Tubeless supra-costal percutaneous nephrolithotomy is associated with significantly less hydrothorax: a prospective randomized clinical study.

OBJECTIVES: To evaluate prospectively whether a tubeless (JJ stent-only) percutaneous nephrolithotomy (PCNL) might reduce the risk of hydrothorax, compared to an approach where a nephrostomy tube is left. MATERIALS AND METHODS: We conducted a two-arm open-label prospective randomized study (NCT02036398) comparing tubeless supra-costal PCNL (with a JJ stent only) to standard PCNL (with nephrostomy tube and JJ stent) using intention-to-treat (ITT) and per-protocol (PP) analyses. All patients underwent a standard single-stage prone supra-costal procedure with single-tract access. Complication data were collected according to the Clavien-Dindo grading system. The primary endpoint was the rate of hydrothorax, and secondary endpoints included stone-free rate (SFR) and complication rate. Multivariable logistic regression analysis identified factors associated with hydrothorax formation. RESULTS: Out of 101 patients approached, 75 were finally analysed. No differences were observed between the two arms with regard to baseline demographic and stone characteristics. The mean largest stone size ranged between 23 and 24.2 mm. No significant difference was seen in the mean operating time and length of hospital stay. The incidence of hydrothorax was significantly higher in the nephrostomy group in comparison to the tubeless group (37.8% vs 15.8%, P = 0.031, and 38.4% vs 13.8%, P = 0.016, in the ITT and PP analyses, respectively). The SFR and complication rate were similar in both groups using the ITT and PP analyses. Multivariable logistic regression analysis showed that nephrostomy tube placement was the only covariate associated in a statistically significant manner to hydrothorax (odds ratio 3.628, 95% confidence interval 1.073-12.265; P = 0.038). CONCLUSION: The rate of hydrothorax in supra-costal PCNL is associated with the type of postoperative drainage left. When possible, a tubeless approach should be applied as it may confer a lower risk of hydrothorax.

Predictors of surgical site infection after radical cystectomy: should we enhance surgical antibiotic prophylaxis?

PURPOSE: To compare surgical site infections (SSI) rate after radical cystectomy (RC) over time and ascertain whether antibiotic prophylaxis should be enhanced. METHODS: All medical records of RC patients in a single tertiary uro-oncology center between 2007 and 2017 were analyzed. SSI was defined using the criteria of the US Centers for Disease Control and Prevention. All bacterial culture results and antimicrobial resistance rates were recorded. Lastly, multivariable logistic regression analysis was performed to ascertain SSI predictors. RESULTS: RC was performed in 405 patients, of which 96 (23.7%) developed SSI. No differences were demonstrated in the mean age, gender, NIDDM prevalence, neoadjuvant chemotherapy, positive preoperative urine culture, bowel preparation, and surgery time between both groups. However, statistically significant higher median BMI, age-adjusted Charlson Comorbidity score, usage of ceftriaxone preoperatively, and intensive care unit (ICU) hospitalization were noted in SSI patients. Overall, 62/96 (63.5%) SSI patients had a positive wound culture, with only 16.7% of the pathogens being sensitive to their perioperative antibiotics. Lastly, on multivariable analysis rising BMI, preoperative ceftriaxone and ICU hospitalization were associated with a higher SSI rate. CONCLUSIONS: Preoperative BMI reduction, and maximal preoperative medical optimization in an attempt to lower ICU admittance rates, should be part of the ideal strategy for lowering SSI rates. Additionally, preoperative antibiotics should be enhanced to harbor-wide spectrum coverage, based on local resistance rates.

Predicting the risk of sepsis and causative organisms following urinary stones removal using urinary versus stone and stent cultures.

The association between foreign objects in the urinary system and urinary tract infections (UTI) is well established. The incidence of bacteriuria in patient with urinary catheters increases as dwelling time lengthens. The presence of ureteral stents and kidney stones is also associated with increased risk for bacteriuria and urinary tract infection. The aim of this study was to assess the bacterial characteristics of urine culture (UC) and foreign body culture (FBC), the concordance between them, and to identify risk factors for postoperative infections, in order to improve the treatment in these patients, using a prospectively collected database of patients who underwent ureteroscopy or percutaneous nephrolithotomy (PCNL) for the treatment of urinary stones between 2005 and 2016 at our institute. Preoperative UC was obtained from voided mid-stream urine for all patients. FBCs were obtained from ureteral stents removed and stones collected during the surgery. The cohort included 1011 patients. Mean age was 53 (SD 15.8), and 679 (67.2%) patients were male. Two hundred eighteen (21.6%) had a UTI in the year prior to the surgery. Among 795 patients who had sterile UC, 98 (12.3%) patients had positive FBC. Positive FBC was found in 53.7% of the patients with positive UC; however, FBC pathogens were similar to those identified in UC in 31% patients. The sensitivity of UC to detect FBC pathogens was 31.3%, and the PPV was 0.31. Urine cultures do not recognize all cases of pathogens colonizing foreign bodies in the urinary system. The colonization may be associated with an increased risk for SIRS. In more than one-quarter of the patients, the causative pathogen of sepsis is identified by FBC, but not by UC.

Stone culture in patients undergoing percutaneous nephrolithotomy: a practical point of view.

INTRODUCTION: To determine the clinical yield of stone culture in patients undergoing percutaneous nephrolithotomy (PCNL), and to identify patients who may benefit from this test. MATERIALS AND METHODS: We queried our database for all patients who underwent PCNL from 2005 to 2017, from whom urine culture (UC) and stone culture (SC) were obtained. Study endpoint was systemic inflammatory response syndrome (SIRS) within 48 hours of PCNL. Risk factors for SIRS and for stone colonization with highly resistant pathogens were evaluated. Based on UC and SC results, we determined the proportion of patients in whom SC may alter the treatment, had SIRS occurred, with respect to the initial empiric treatment. RESULTS: The study group comprised of 512 patients with a median age of 53, of whom 323 (63%) were male. Positive UC were found in 137 (26.7%) patients, and positive SC in 117 (22.8%) patients. UC did not identify pathogens isolated from SC in 66 (12.8%) patients. Postoperative SIRS occurred in 50 (9.8%) patients. On multivariate analysis only SC was associated with postoperative SIRS. SC pathogens resistance rates ranged from 67% for treatment with 2nd generation cephalosporins to 9% for treatment with meropenem, and may alter the choice of antibiotics in 73 to 12 patients (14.2%-2.3% of the whole cohort), respectively. CONCLUSIONS: In similar and earlier studies, we found substantial discordance between SC and UC results, and an association between stone colonization and SIRS. However, the practical yield of this test varies with the type of antibiotic given, and is limited when broad spectrum antibiotic is used.

Clinical Implications of Stent Culture in Patients with Indwelling Ureteral Stents Prior to Ureteroscopy.

PURPOSE: We determined the ability of urine culture to predict stent culture status and associated infectious pathogens, and evaluated the association between stent culture and post-ureteroscopy sepsis. MATERIALS AND METHODS: We queried the prospectively collected database at our institution and identified all patients who underwent ureteroscopy between October 2010 and August 2016 who had a ureteral stent before the operation and from whom urine and stent cultures were obtained. The study end point was post-ureteroscopy sepsis within 48 hours of the procedure. We compared urine and stent culture findings, and performed univariate and multivariate analyses to identify predictors of post-ureteroscopy sepsis. RESULTS: The study group comprised 509 patients with a median age of 56 years, of whom 147 (28.9%) were female. Positive urine cultures were found in 91 patients (17.8%) and positive stent cultures were found in 104 (20.4%). Urine and stent cultures were positive in 48 patients (9.4%), of whom only 24 had identical bacteria in both cultures. The most common pathogens isolated from urine and stent cultures were Escherichia coli in 38.5% and Enterococcus in 18.4%. Sepsis developed in 25 patients (4.9%), including 21 (84%) with a positive stent culture and 14 (59%) with a positive urine culture. On multivariate analysis female gender and positive stent culture were significantly associated with post-ureteroscopy sepsis. CONCLUSIONS: Only half of the patients with ureteral stents prior to ureteroscopy, and positive stent and urine cultures had similar pathogens in both cultures. Female gender and positive stent culture were associated with a higher risk of post-ureteroscopy sepsis in this population. Stent culture may direct the proper antibiotic treatment in patients with sepsis after ureteroscopy.

Ureteric stent dwelling time: a risk factor for post-ureteroscopy sepsis.

OBJECTIVES: To evaluate the association between stent dwelling time and sepsis after ureteroscopy, and identify risk factors for sepsis in this setting. PATIENTS AND METHODS: The prospectively collected database of a single institution was queried for all patients who underwent ureteroscopy for stone extraction between 2010 and 2016. Demographic, clinical, preoperative and operative data were collected. The primary study endpoint was sepsis within 48 h of ureteroscopy. Logistic regressions were performed to identify predictors of post-ureteroscopy sepsis in the ureteroscopy cohort and specifically in patients with prior stent insertion. RESULTS: Between October 2010 and April 2016, 1 256 patients underwent ureteroscopy for stone extraction. Risk factors for sepsis included prior stent placement, female gender and Charlson comorbidity index. A total of 601 patients had a ureteric stent inserted before the operation and were included in the study cohort, in which the median age was 56 years, 90 patients were women (30%), and 97 patients were treated for positive preoperative urine cultures (16.1%). Postoperative sepsis, <48 h after surgery, occurred in eight (1.2%) non-stented patients and in 28 patients (4.7%) with prior stent insertion. Sepsis rates after stent dwelling times of 1, 2, 3 and >3 months were 1, 4.9, 5.5 and 9.2%, respectively. On multivariate analysis, stent dwelling time, stent insertion because of sepsis, and female gender were significantly associated with post-ureteroscopy sepsis in patients with prior stent placement. CONCLUSIONS: Patients who undergo ureteroscopy after ureteric stent insertion have a higher risk of postoperative sepsis. Prolonged stent dwelling time, sepsis as an indication for stent insertion, and female gender are independent risk factors. Stent placement should be considered cautiously, and if inserted, ureteroscopy should be performed within 1 month.

The role of diagnostic ureteroscopy in the era of computed tomography urography.

BACKGROUND: To examine the contemporary role of ureteroscopy in the diagnosis of upper urinary tract urothelial carcinoma. METHODS: We retrospectively evaluated 116 diagnostic ureteroscopies, performed in our institution to rule out primary UTUC. Demographics, cytological findings and interpretation of preoperative imaging were obtained. Ureteroscopic diagnosis and histological results were recorded and the predictive values of diagnostic studies were determined. Follow-up data was reviewed to evaluate the oncological outcomes in patients treated endoscopically. RESULTS: The pre-ureteroscopic evaluation included CTU in 91 (78%) patients. Positive and Negative predictive values of CTU were 76 and 80%, respectively. Typical filling defect on CTU was demonstrated in 38 of 89 patients. UTUC has been ruled out in 9 patients (24%) with suspicious filling defect on CTU. Endoscopic approach was implemented in 7 patients (18%). During a median follow up period of 17 months (IQR, 9-25) none of the followed patients experienced disease progression. CONCLUSIONS: Nephroureterectomy was spared from 42% of patients who underwent diagnostic ureteroscopy for suspected UTUC, demonstrated on CTU. In about half of those patients tumor has been ruled out and the others were managed endoscopically. Therefore, diagnostic ureteroscopy is advised as a crucial step in confirming UTUC and treatment planning.

Oncologic results of nephron sparing endoscopic approach for upper tract low grade transitional cell carcinoma in comparison to nephroureterectomy - a case control study.

BACKGROUND: There is paucity of data as to the results of the endoscopic approach in comparison to the golden standard of nephro-ureterectomy in elective, low grade TCC, patients. Our purpose is to report our results of a nephron sparing approach compared to nephro-ureterectomy in those patients. METHODS: From a retrospective data base we identified 25 patients and 23 patients who underwent a nephron sparing ureterosocpic resection and nephro-reterectomy for low grade UT-TCC, respectively. The endoscopic technique included endoscopic tumor biopsy followed by primary resection and/or fulguration. The nephron sparing group was followed by bi-annual ureteroscopy and upper tract imaging, timely cystoscopy and urine cytology collection. Data for overall and disease related mortality, bladder and ureteral TCC recurrence and renal function are reported in both groups. RESULTS: Median follow - up time was 26 months. 11 (44%) patients developed bladder recurrence at a median period of 9 months after initial ureteroscopy, compared to 9 (39%) in the NUx group (P < 0.05). Recurrent ureteral low grade TCC was observed in 9 patients (median: 9 months). All were treated endoscopicaly successfully. Renal function remained stable in the nephron sparing group. No disease related mortality was recorded in the nephron-sparing group while one patient died of his disease following NUx. CONCLUSIONS: Disease related mortality following a nephron sparing endoscopic approach or nephroureterectomy for low grade upper tract TCC is excellent. However, the nephron sparing approach is associated with a relatively high rate of ureteral and bladder recurrence. Therefore, a stringent follow-up protocol is required.

Propensity Score-Matched Analysis of Perioperative Outcomes of Supine versus Prone Percutaneous Nephrolithotomy.

Objective: To compare the perioperative outcomes of supine and prone percutaneous nephrolithotomy (PCNL). Methods: A retrospective search of a tertiary medical center database yielded 517 patients who underwent supine (n = 91) or prone (n = 426) PCNL between September 2015 and July 2020. Data on demographics, baseline clinical parameters, and stone burden were included as predictors in a logistic regression model, generating a set of propensity scores. Seventy patients after supine PCNL were propensity score-matched 1:1 with patients after prone PCNL and compared for operative time, perioperative complications, system complexity, and stone-free rate. Results: We found that the operative time was significantly shorter in the supine PCNL group than in the prone PCNL group (85.5 ± 25.2 min vs. 96.4 ± 25.8 min, respectively; p = 0.012). The majority of both groups had low-grade (I-II) complexity systems (85.6% and 88.6%, respectively), with no significant difference among all grade groups (p = 0.749). There were no significant differences between the supine and prone PCNL groups in terms of the overall perioperative complication rate (8.6% vs. 4.3%, respectively; p = 0.301) or stone-free rate (74.3 vs. 65.7%, respectively; p = 0.356), while the rate of blood transfusion was significantly higher in the supine group (p = 0.023). Conclusions: In our study, we used propensity score matching to compare patients who underwent PCNL in the supine or prone position, adjusting for selection bias. Supine PCNL was associated with a shorter operative time but a higher blood transfusion rate, with no differences in the overall complication and stone-free rates.

Pediatric Age-Related Distribution of Calcium Oxalate Monohydrate and Calcium Oxalate Dihydrate in Urinary Tract Stones: Metabolic, Gender, and Ethnic Correlates.

Introduction: Previous studies of pediatric urolithiasis have suggested possible associations between the relative proportions of calcium oxalate dihydrate (COD) and calcium oxalate monohydrate (COM) stones with age, gender, and ethnicity. This study aimed to investigate the composition and distribution of calcium oxalate (CaOx) stones according to these clinical factors and the metabolic correlates of the different subtypes in pediatric stone formers (PSFs). Patients and Methods: We retrospectively reviewed the database of all first-time stone formers between 2014 and 2019. Infrared spectrometry was used to determine stone composition. Stones were categorized by their highest relative component and reported as a percentage of occurrences in the cohort as a whole and by patient gender, age (divided into three age groups: 1-5, 6-12, and 13-18 years), and ethnicity. Clinical and metabolic correlates were analyzed. Results: Of 2479 consecutive stones submitted to our chemical stone laboratory, 220 first-time PSFs were identified. COD stones were the predominant subtype in the youngest group, and COM stones in the oldest group (odds ratio 0.39, 95% confidence interval: 0.18-0.86, p = 0.036). In the intermediate-age group (6-12 years), COM stones were more prevalent in Arab boys, and COD stones in girls of either ethnicity. COD stones were associated with hypercalciuria (p < 0.0001), and COM stones with hyperoxaluria (p = 0.0024). Hypercalciuria and hypocitraturia were the most prevalent abnormalities at ages 1 to 5 and 13 to 18 years, respectively. Conclusions: Analysis of CaOx stone subtypes and their metabolic correlates in stone formers has significant clinical relevance, specifically in children. In the present study, COD stones and hypercalciuria were more common in younger children, and COM stones and hypocitraturia in adolescents. These findings suggest unique complex interactions driving stone formations in children that may guide a more practical, limited, and cost-effective approach to metabolic evaluations, choice of treatment, and preventive measures, particularly in first-time CaOx PSFs.

Post-operative pain following percutaneous nephrolithotripsy- clinical correlates.

OBJECTIVES: Management of postoperative pain following percutaneous nephrolithotripsy (PCNL) is a significant goal. We sought to identify risk factors and clinical correlates of postoperative pain in order to improve perioperative management and patient satisfaction. MATERIALS AND METHODS: A single-center, retrospective analysis, from a prospectively maintained database, of all consecutive patients who underwent PCNL for renal calculi between January 2011 and August 2018. Postoperative pain was assessed using the visual analog scale (VAS) and analgesic use. We considered VAS score above 4 as meaningful. Pain management was standardized according to patirnt reported VAS scores. Multivariable logistic regression was performed to identify risk factors and clinical correlates. RESULTS: A total of 496 patients were analyzed. Younger age was associated with VAS above 4 on the operative day and the first postoperative following PCNL (p = 0.003 and p < 0.001, respectively). Female gender was associated with VAS above 4 in the first 2 days following the operation (p < 0.001). CONCLUSIONS: Younger age and female gender would most likely benefit from pre-emptive improved pain management protocols following PCNL.

Retrograde intrarenal surgery for lower pole stones utilizing stone displacement technique yields excellent results.

Objective: To evaluate the long-term stone-free rate (SFR) of retrograde intra-renal surgery (RIRS) in the treatment of lower pole renal calculi using only basket relocation and identify independent predictors of stone-free status. Methods: All consecutive patients undergoing RIRS lower pole renal calculi at a single high-volume tertiary center were analyzed retrospectively. Lower pole stones were relocated to the upper pole, where laser lithotripsy was performed. All patients were followed up in the clinic following the surgery and yearly thereafter. The stone-free status was assessed with a combination of an abdominal ultrasound and abdominal X-ray, or an abdominal non-contrast computed tomography if the stones were known to be radiolucent. Results: A total of 480 consecutive patients who underwent RIRS for treatment of lower pole renal calculi, between January 2012 and December 2018, were analyzed from a prospectively maintained database of 3000 ureteroscopies. With a median follow-up time of 18.6 months, the mean SFR was 94.8%. The procedures were unsuccessful in 26 (5.4%) patients due to unreachable stones. The median stone size of the unreachable stones was 12 mm (range 10-30 mm). Multivariable logistic regression analysis revealed two predictors of SFR for lower pole stones: a small cumulative stone burden (odds ratio [OR]: 0.903, 95% confidence interval [CI]: 0.867-0.941, p<0.0001) and preoperative ureteral stent insertion (OR: 0.515, 95% CI: 0.318-0.835, p=0.007). Conclusion: The long-term SFR of RIRS for the treatment of lower pole stones with basket displacement with appropriate patient selection is high.

Endoscopic Management of Low-Grade Upper Tract Urothelial Carcinoma: Characterizing the Long-term Burden of Care in Comparison to Radical Nephroureterectomy.

OBJECTIVE: To compare procedure burden, oncologic, surgical and renal-function outcomes between patients with low-grade upper urothelial cancer (UTUC) who were referred for either radical management (RM) or kidney-sparing endoscopic management (EM). PATIENTS AND METHODS: We retrospectively reviewed data of all patients treated for UTUC at our tertiary medical center between 2000 and 2018 and selected patients diagnosed with unilateral low-grade UTUC. RESULTS: Twenty-four patients were treated with EM and 37 with RM. Surgical and oncologic risk factors were similar between the arms except for tumor size. Mean follow-up was 4.9 ± 3.4 years. The 5-year overall-survival rate was 85% with EM and 84% with RM (P = .707). Metastasis-free and cancer-specific survival were also similar (P = .994, P = .960). End-of-follow-up average glomerular filtration rates were 58.7 ± 21.5 and 49.2 ± 22.1 mL/min/1.73 m2, respectively (P = .12). Ninety-two percent of patients managed endoscopically had local recurrences, with an average of 3.2 recurrences per patient. Four (17%) patients underwent salvage radical nephroureterectomy. Procedure burden was higher with EM, having 6.5 ± 4.4 operations and 344 ± 272 minutes under anesthesia compared with 1.9 ± 0.4 operations (P <.0001) and 213 ± 84 minutes under anesthesia (P = .031) with RM. Cost-of-care analysis revealed higher costs for EM in both private and publicly funded medical insurance plans. CONCLUSION: Patients undergoing endoscopic management had an 83% chance of preserving their kidney and an 81% chance of 5-year metastasis-free survival at a cost of 6.5 ± 4.4 operations during a mean follow-up of 4.9 ± 3.4 years. Our findings support EM for low-grade UTUC as a valid option from oncological aspects but highlight the associated costs.

Do Infection-Associated Stone Subtypes Behave the Same Clinically? A Retrospective Bicenter Study.

Introduction and Objectives: Infection-associated renal stones are commonly composed of magnesium-ammonium-phosphate (MAP) and carbonate apatite (CA). The clinical implications of these two different, but closely related stone types, are unknown. We sought to compare the clinical, microbiologic, and metabolic characteristics of patients with MAP and CA stone types. Methods: We retrospectively reviewed the medical records of patients from two centers (one in the United States and one in Israel) who underwent ureteroscopy or percutaneous nephrolithotomy between 2012 and 2020 and identified patients with a predominant stone analysis component of CA or MAP and clinical data supporting an infection stone. We analyzed and compared demographic data, medical history, postoperative fever, stone and urinary microbiology, and 24-hour urine studies. Results: A total of 79 and 75 patients met the inclusion criteria for the MAP and CA cohorts, respectively. No significant difference was found in patient demographics or comorbidities between the MAP and CA cohort. Female predominance was noted in both. Although there were no significant differences in 24-hour urine parameters between the cohorts, hypercalciuria was common in both cohorts (38% and 32% of patients in the MAP and CA cohorts, respectively). Gram-negative bacteria were more common in the MAP stone cultures. Postoperative fever was significantly more common in the MAP cohort (14.7% vs 3.8%, p < 0.016). Conclusions: MAP and CA stone formers share similar demographic characteristics with a clear female predominance. MAP stones patients appear more likely to develop postoperative fever, possibly related to a higher occurrence of gram-negative bacteria in the stone cultures of the MAP cohort. Although there were no significant differences among metabolic parameters, hypercalciuria was noted in approximately a third of the cohort. The clinical significance of this finding is yet to be determined.

Histopathological predictors of renal function decrease after laparoscopic radical nephrectomy.

PURPOSE: Radical nephrectomy is inevitably associated with a variable renal function decrease. We assessed the association of histopathological parameters in nonneoplastic renal parenchyma with the renal function decrease after radical nephrectomy. MATERIALS AND METHODS: We evaluated 32 male and 17 female patients with a mean age of 55.9 years who underwent laparoscopic radical nephrectomy. Using the Cockcroft-Gault formula we calculated the estimated glomerular filtration rate preoperatively and at last followup at a mean of 19.7 months. The study end point was the percent change in the estimated glomerular filtration rate from baseline, defined as (absolute change/baseline) × 100. Three histological features in the nonneoplastic parenchyma were assessed by a renal pathologist, including global glomerulosclerosis, arteriosclerosis and interstitial fibrosis/tubular atrophy. For glomerulosclerosis assessment the percent of affected glomeruli was determined. Arteriosclerosis or the extent of arterial luminal occlusion was graded into 4 groups, including 1-0% to 5%, 2-6% to 25%, 3-26% to 50% and 4-greater than 50%. However, due to small patient numbers groups 1 and 2, and 3 and 4 were condensed, and AS was statistically evaluated as 0% to 25% or greater than 25%. Interstitial fibrosis/tubular atrophy was evaluated as absent/present. RESULTS: The mean estimated glomerular filtration rate decreased 31% from 122 to 85 ml/minute/1.73 m(2) after surgery (p < 0.0001). The percent change in the estimated glomerular filtration rate was associated with glomerulosclerosis extent (p = 0.034). For each 10% increase in glomerulosclerosis the estimated glomerular filtration rate decreased by 9% from baseline. The extent of arteriosclerosis or the presence of interstitial fibrosis/tubular atrophy did not correlate with the estimated glomerular filtration rate decrease. CONCLUSIONS: Glomerulosclerosis severity in nonneoplastic parenchyma can predict the rate of renal function decrease after radical nephrectomy. This histopathological parameter should be assessed in all tumor nephrectomy specimens, given that preserving renal function is important for quality of life and clinical outcome in patients with renal cancer.

Impact of ischemia on renal function after laparoscopic partial nephrectomy: a multicenter study.

PURPOSE: We assessed the influence of renal ischemia on long-term global renal function after laparoscopic partial nephrectomy in patients with 2 functioning kidneys in a large, multicenter cohort. MATERIALS AND METHODS: Collected data included demographic, clinical and surgical characteristics, tumor parameters and renal function outcomes at 4 institutions in a total of 401 patients with 2 functioning kidneys who underwent laparoscopic partial nephrectomy. Renal function was assessed in the immediate postoperative period (days 1 to 3) and at last followup (greater than 1 month) using the estimated glomerular filtration rate calculated by the 4-variable Modification of Diet in Renal Disease equation. Ischemia time and covariates were modeled on the percent change in the estimated glomerular filtration rate using linear regression. RESULTS: Median ischemia time was 29 minutes (IQR 22, 34). The postoperative change and the last (long-term) change in the estimated glomerular filtration rate were -16% and -11%, respectively. Median time to the last estimated glomerular filtration rate measurement was 13 months (IQR 6, 24). On multivariate analysis shorter ischemia and operative times, external or ureteral irrigation with cold saline and female gender were associated with less postoperative percent change in the estimated glomerular filtration rate. Smaller tumor size and absent diabetes were associated with less of a final percent change in the estimated glomerular filtration rate. Ischemia time was not associated with a percent change in the estimated glomerular filtration rate at last followup. CONCLUSIONS: Within the range of times in these series renal ischemia did not have a clinically significant impact on global renal function in patients with 2 functioning kidneys who underwent laparoscopic partial nephrectomy, as measured by the estimated glomerular filtration rate.