Malignant Ureteral Obstruction Research Articles

Allium covered metal stent for treatment of malignant ureteral obstruction.

Malignant ureteral obstruction (MUO) has the potential to result in a range of outcomes, including varying degrees of hydronephrosis and renal impairment. Allium covered metal stents have provided a new, highly effective treatment option for MUO. Our objective was to evaluate the safety and efficacy of the Allium covered metallic stent for the treatment of malignant ureteral obstruction. Clinical data of 29 patients who underwent endoscopic insertion of an Allium ureteral stent between October 2019 and August 2021 at Yongchuan Hospital, affiliated with Chongqing Medical University, were analyzed retrospectively. At one, three, six and 12 months after insertion, serum creatinine was measured, the width of the renal pelvis was rechecked under ultrasound guidance, and the position and shape of the stent were checked by abdominal x-ray. Data on long-term stent patency, incidence of complications, changes in renal function and hydronephrosis grade were collected and analyzed. Ureteral stent symptom questionnaire (USSQ) was administered preoperatively and after six months in 22 patients with previous stent history. Allium covered metal stents (n = 33) were implanted successfully in 29 patients who were followed for three to 22 months, with 32/33 stents remaining patent. Serum creatinine levels decreased in 17 patients (p < 0.001), and hydronephrosis decreased in 24 patients. Clavien-Dindo grade I complications were observed in seven patients, Clavien-Dindo II in one patient, whereas stent displacement and stent encrustation occurred in one patient each (Clavien-Dindo III-IV). USSQ scores had significantly improved six months after stent insertion (p < 0.001). Allium ureteral stents are a safe and effective treatment option for malignant ureteral obstruction, with good long-term patency, helping to preserve renal function and improve quality of life.

Antegrade stenting for chronic malignant ureteral obstruction with the Resonance® metallic stent: a case series.

Polymeric and metallic stents are commonly used to manage patients with chronic malignant ureteric obstruction (CMUO). This paper compares the outcomes of ureteral stenting via the Resonance® metallic stent against its polymeric counterpart in published literature, as well as between antegrade and retrograde approaches. A retrospective case series was conducted whereby patients who had undergone Resonance® stent insertions via an antegrade route from June 2022 to May 2023 were reviewed through our electronic medical record system. Descriptive statistics were used to summarise patient demographics and clinical outcomes. 11 patients who presented with CMUO underwent 12 separate procedures of either unilateral or bilateral ureteral stenting. Total number of stents inserted was 16. Median age of patients was 65 (Range = 32) and 72.73% were males. 66.67% of the procedures yielded an improvement in the estimated glomerular filtration rate (eGFR) in patients as compared to before stenting. Stent failure, defined by stent removal before recommended removal date, occurred in 4 out of 16 (25%) stents. The median duration of Resonance® stent in situ at the time of data collection (4th December 2023) was 245days. We conclude that the Resonance® stent is more effective at providing long term urinary drainage for CMUO, compared to its polymeric counterpart. However, antegrade insertion of the Resonance® stent does not significantly decrease indwelling stent duration compared to retrograde insertion.

Urinary Diversion Can Improve the Chance of Implementing New Therapeutic Lines in Patients with Malignant Ureteral Obstruction: A Multicenter Study.

Malignant ureteral obstruction is generally associated with a poor disease prognosis; therefore, managing these cases is challenging. We describe our experience in treating malignant ureteral obstruction with urinary diversion and the impact of these procedures on the indication for new antineoplastic therapy and survival. We retrospectively reviewed the data of patients with advanced cancer associated with malignant ureteral obstruction who underwent urinary diversion at three tertiary institutions between January 2013 and July 2022. This study included 420 patients (mean age, 58.7 years (range, 18-90 years) with a mean follow-up of 20.3 months. Cervical (36.2%) and bladder cancers (18.6%) were the most prevalent primary neo-plastic sites. The mean creatinine values measured before diversion, 30 days after surgery, and most recently were 3.45, 1.84, and 2.59 mg/dL, respectively. In total, 300 patients (71.4%) received antineoplastic treatment, 195 received palliative treatment, and 105 received curative treatment. After an average of 251.87 postoperative days, 265 (64%) patients died. The mean overall survival was 610.76 days. Patients with prostate and cervical neoplasms had the most prolonged overall survival (573.13 and 549.28 days, respectively), whereas patients with bladder and colorectal cancer had the worst overall survival (480.25 and 370.53 days, respectively). Urinary diversion improves kidney function and opens a therapeutic window for a new line of antineoplastic therapy that provides a cure or increases patient survival.

Outcomes of nephrostomy and double J stent in malignant ureteral obstruction in the Palestinian practice

BackgroundMalignant ureteral obstruction (MUO) is a serious health condition in which a malignant tumor compresses the ureter. The optimal decompressive intervention in MUO remains unclear. This study was conducted to assess and compare renal function, the occurrence of ureterohydronephrosis (UHN), intraoperative, and postoperative complications among patients with MUO who underwent double J stenting (DJS) and percutaneous nephrostomy (PCN) in the Palestinian practice.MethodsThis study was conducted in retrospective design in one of the main tertiary care hospitals in the West Bank of Palestine. The data were collected from the electronic health information system of the hospital for the patients with MUO who received either DJS or PCN as a decompressive intervention from January 2018 to January 2024.ResultsIn this retrospective analysis, 62 patients who had stage 2 to stage 4 cancer and suffered MUO were included. The mean age of the patients was 60.8 ± 13.6 years. Of the patients, 40 (64.5%) were male and 22 (35.5%) were female. Of the patients, 26 (41.9%) had urinary bladder cancer. Of the patients, 23 (37.1%) had flank pain and 16 (25.8%) had lower urinary tract symptoms. Of the patients, 34 (54.8%) experienced bilateral UHN and 28 (45.2%) experienced unilateral UHN. In this study, 43 patients (69.4%) received PCN, and 19 (30.6%) received DJS as a decompressive intervention. Of the patients, 36 (58.1%) suffered postoperative complications. Stent migration/slip, UTIs, and urosepsis were the most commonly reported postoperative complications. There were no statistically significant differences in the occurrence of intraoperative complications, postoperative complications, time elapsed from receiving the decompression intervention to the diagnosis of complications, ICU admission, prognosis of UHN, serum creatinine, and serum BUN between both decompressive interventions.ConclusionDespite improvements in renal functions, creatinine and BUN levels remained abnormal even after receiving a decompressive intervention. Postoperative complications were frequently reported among patients who received DJS or PCN as decompressive interventions. Larger prospective studies are still needed to determine the optimal interventions to improve outcomes, quality of life, and survival rates of patients with DJS or PCN.

Urogenital schistosomiasis, a leading cause of bladder squamous cell carcinoma

Abstract Introduction/Objective Schistosoma, genus of trematodes, commonly known as blood flukes are parasitic flatworms responsible for a group of infections in humans termed schistosomiasis and hundreds of millions of people are infected worldwide. In areas where Shistosoma is not endemic to the region most cases of bladder malignancy are of urothelial origin. In areas where Shistosoma is endemic bladder malignancy is more commonly squamous cell carcinoma. However, with increased travel, migration and tourism it is important to potentially consider Shistosoma infection in areas that are not typically considered endemic regions. Methods/Case Report A 62-year-old male presented to our hospital and revealed through an interpreter he has had 1.5 years hematuria with “pieces of meat or brown dirt”. Cystoscopy was performed and showed a large necrotic mass. CT scan showed an 8.2 cm exophytic bladder dome mass. TURBT was performed and a diagnosis of invasive high-grade urothelial carcinoma with squamous differentiation and with multiple Schistosoma organisms identified.The patient received Schistosoma treatment and was scheduled for radical cystectomy and ileal conduct. A few days before the scheduled procedure the patient presented to our emergency department with acute abdominal pain. He was subsequently diagnosed with progressive bladder cancer with new left malignant ureteral obstruction, which lead to hydronephrosis, DVT, abdominopelvic ascites and intraperitoneal bladder perforation. Abdominal fluid cytology showed atypical keratinizing squamous cells suspicous for malignancy and marked acute inflammation. Patient underwent cystectomy with ileal conduit and the specimen was sent to pathology for examination. Results (if a Case Study enter NA) NA Conclusion Gross examination showed an irregular perforated bladder. Microscopic examination showed a high grade urothelial carcinoma with squamous and sarcomatoid differentiation with detrusor muscle invasion. Additionally, Schistosoma organisms with a terminal spine and calcified eggs were identified. Some of the calcified egg material was engulfed by giant cells. The organisms are surrounded by a prominent eosinophilic infiltrate. Lymphovascular invasion is also noted. Schistosomiasis is associated with the development of squamous cell carcinoma of the bladder. It is important to maintain high oncological alertness for squamous cell carcinoma, particularly for patients arriving from endemic areas. Such as in our case, a patient from Somalia living in Kansas City.

Cost‐effectiveness of Resonance® metallic ureteral stent compared with standard polyurethane ureteral stents in malignant ureteric obstruction: A cost‐utility analysis

AbstractBackgroundMalignant ureteral obstruction (MUO) is a frequent challenge for urologists. Patients have poor prognoses, treatment aims to improve quality‐of‐life while optimising renal function. Standard practice in the United Kingdom is to use polyurethane stents, which require frequent surgical replacements for blockages and encrustation. More durable metallic stents are available, although these incur an increased initial purchase price.AimsWe aim to assess whether the use of polyurethane double‐J (JJ) or metallic stent, Resonance® is more cost‐effective for managing MUO in the UK healthcare setting.MethodsA Markov model was parameterised to 5 years with costs and health‐related quality‐of‐life consequences for treating MUO with Resonance metallic stent (Cook Medical), versus standard JJ stents, from the UK care system perspective, with 3.5% discounting. Deterministic and probabilistic sensitivity analyses were undertaken to assess the effect of uncertainty.ResultsOver 5 years, approximately four fewer repeat surgical interventions were estimated in the metallic stent arm compared with the JJ stent, driving a 23.4% reduction in costs. The mean estimates of costs and benefits indicate that treatment of MUO with Resonance for 5 years is dominant over JJ stents. Over 5 years a cost‐saving of £2164.74 and a health gain of +0.046 quality‐adjusted life years (QALYs) per patient is estimated. With a maximum willingness to pay of £20 k per QALY, a net monetary benefit (NMB) of £3077.83 is estimated. Probabilistic sensitivity analysis at a willingness to pay threshold of £20 000 indicates an 89.3% probability of Resonance being cost‐effective over JJ stents. Within 1‐year savings of £726.53 are estimated driven by a reduction of two fewer repeat surgical interventions when using the metallic stent.ConclusionsResonance metallic stents for the treatment of MUO reduce the number of repeat procedures and could be a cost‐effective option for the treatment, potentially offering efficiencies to the healthcare system.

Malignant ureteral obstruction: comparison of metallic, 8 French and 6 French ureteric stents after failure of initial ureteric stent.

Malignant ureteric obstruction is a significant management challenge. The failure of ureteric stents often leads to long-term nephrostomy tubes. This is delayed for as long as possible due to its' associated morbidity. Several types of ureteric stents are available, however there is little evidence demonstrating which stents are better for preventing progression to nephrostomy tubes. This study looked to determine whether a new 6 French (Fr) polymer stent, 8Fr polymer stent or metallic stent achieved a longer functional duration once the initial polymer ureteric stent failed. A retrospective, longitudinal study was performed at a single tertiary institution. All patients who underwent ureteric stenting with a 6Fr polymer stent for malignancy between 2010 and 2020 were included. Patients were followed up until death with ureteric stent in situ or permanent nephrostomy tube insertion. A total of 46 patients (66 ureters) had ureteric stents inserted for malignancy. From initial ureteric stent failure, 10 stents were changed to a new 6Fr polymer stent, 42 were changed to an 8Fr polymer stent and 14 were changed to a Resonance® 6Frmetallic stent. The Resonance 6Fr metallic stent had the longest median functional duration of 14months (p = 0.012). Resonance® 6Fr metallic stents appear to have a significantly longer functional duration than a new 6Fr polymer stent or 8Fr polymer stent, which may allow patients to enjoy a better quality of life and delay permanent nephrostomy tube insertion.

Longitudinal Outcomes of Malignant Ureteral Obstruction Secondary to Ovarian Cancer: Predictors of Resolution and the Role of Surgical Management

PurposeTo review the management of ovarian cancer (OCa) associated hydronephrosis (HN). Specifically, we aim to identify optimal management of HN in the acute setting, predictors of HN resolution, and the role of surgery (tumor debulking/(+/-)ureterolysis/hysterectomy). Materials/MethodsThe study cohort included OCa patients managed at our institution from 2004-19 that developed OCa-associated HN. Initial HN management was recorded as none, retrograde ureteral stent (RUS) or percutaneous nephrostomy tube (PCN). Primary outcomes included 1) HN management failure 2) HN management complications and 3) HN resolution. Patient, cancer, and treatment predictors of outcomes were assessed using logistic regression and Fine-Gray competing risk models. ResultsOf 2580 OCa patients, 190 (7.4%) developed HN. HN was treated in 121; 90 (74.4%) with RUS, 31 (25.6%) with PCN. Complication rates were similar between PCN and RUS (83% v. 85.1%; p = 0.79; all Clavian Grade I/II). Initial HN treatment failure occurred in 28 patients, predicted by renal atrophy (HR 3.27, p<0.01). HN resolution occurred in only 52 (27%) patients and was predicted by lower FIGO stage (FIGO III/IV HR 0.42 p<0.01) and surgical tumor debulking/ureterolysis (HR 2.83 p = 0.02). ConclusionsResolution of HN associated with malignant obstruction from OCa is rare and is most closely associated with tumor debulking and FIGO stage. Initial endoscopic treatment modality was not significantly associated with complications or resolution, though RUS failures were slightly more commonly. Ureteral reconstruction at time of debulking/ureterolysis is potentially underutilized.

Management of malignant ureteric obstruction with ureteric stenting or percutaneous nephrostomy.

Lay summary Malignant ureteric obstruction (MUO) is frequently encountered in patients with advanced cancers. In the largest study to date, assessing 852 patients from across Scotland, the authors demonstrated the presence of MUO as a marker of advanced disease across cancer types, with poor survival for many patients, even with intervention. There is uncertainty in optimal management of this condition, with marked differences in management between hospitals. Treatment to relieve the obstruction does not guarantee either improvement in kidney function or progression to further oncological treatment. The authors have developed a prognostic tool to estimate outcomes after intervention for MUO, and advocate its use for clinicians along with other data presented for patient counselling.

The Current Status of Palliative Care, Hospice, and End-of-Life Health Care Utilization in Patients With Malignant Ureteral Obstruction.

Malignant ureteral obstruction is associated with a poor prognosis, with a median survival of 3 to 7 months. These patients are ideal candidates for concurrent palliative care services, consistent with American Society of Clinical Oncology guidelines. We aimed to characterize palliative care, hospice, and end-of-life health care utilization in patients with malignant ureteral obstruction. Patients ≥ 18 years old at our institution and diagnosed with malignant ureteral obstruction between May 2014 and August 2020 were retrospectively identified and pertinent data extracted. Palliative care, hospice, and end-of-life health care utilization was described, and factors associated with each were assessed with logistic regression models. Overall survival was assessed with Cox proportional hazard regression models. One hundred fifteen patients qualified for analysis; 39.1% (45/115) utilized palliative care and spent a median of 12.5 days (IQR 3-52 days) on nonhospice palliative care. On adjusted analysis Black ethnicity (aOR 3.44, 95% CI: 1.08-10.94) was associated with palliative care utilization. Of the patients, 53.9% (62/115) utilized hospice. The median time from hospice initiation to death was 12 days (IQR 5-23 days). On adjusted analysis, prior extirpative surgery (aOR 3.63, 95% CI 1.01-13.05) and palliative care utilization (aOR 4.38, 95% CI 1.70-11.31) were associated with hospice utilization. Median survival following diagnosis was 141 days (IQR 37.5-442.5). Of the patients, 43.0% (37/86) had high end-of-life health care utilization. On multivariable analysis, only hospice (aOR 0.03, 95% CI 0.01-0.14) was associated with less end-of-life health care utilization. Palliative care is underutilized in malignant ureteral obstruction. Hospice, but not palliative care utilization, was associated with decreased end-of-life health care utilization.

Percutaneous Nephrostomy Versus Retrograde Ureteral Stent for Management of Malignant Ureteral Obstruction in Adults: a Systematic Review of the Literature

BackgroundMalignant ureteral obstruction (MUO) is a common presentation in advanced urological and non-urological malignancies. Percutaneous nephrostomy (PCN) and retrograde ureteral stent (RUS) are the most commonly performed procedures to relieve the obstruction. The comparative effectiveness of PCN and RUS for decompression of MUO remains uncertain.PurposeTo systematically review the literature for evidence of improved efficacy of one of these procedures in terms of renal function preservation and clinical outcomes.MethodsWe searched Ovid Medline, Ovid EMBASE, CINAHL, Cochrane Central Register of Controlled Trials (CENTRAL), and Scopus from the date of inception to October 2022. In addition, gray literature was searched through OpenGray (https://opengrey.eu/), dissertation and thesis database (ProQuest) via (https://www.proquest.com), and Clinical trial.gov website. The reference lists of all the included studies were also searched.Two reviewers independently reviewed and selected studies, assessed the quality, and extracted the data.ResultsOverall, 25 eligible studies including 1864 patients compared PCN and RUS (head-to-head). PCN and RUS were found to be similarly effective in improving renal function. However, PCN appears to be superior in maintaining this reduction. The complication rate and quality of life were comparable between the 2 methods, but the length of hospital stay and the financial cost were significantly higher in the PCN group. The mean technical success rate in RUS was 70.3% (21% to 100%) and in PCN was 98.8% (90% to 100%). The conversion rate from RUS to PCN ranged from 10% to 42.6% (mean = 22.5%), while internalization of the PCN occurred in 11.7% to 98% of the patients (mean = 45.5%).ConclusionsBoth diversional methods are effective in management of MUO. However, because of the heterogeneity of the included studies, the superiority of one of the procedures cannot be concluded.

140 Five Year Single-Unit Experience and Outcomes of Renal Decompression for Ureteral Obstruction: A Retrospective Analysis of 102 Kidney Units

Abstract Aim Renal decompression following ureteral obstruction is a common urological emergency. Malignant obstruction patients often have poor life-expectancy, and the impact of decompression on survival is questionable [1]. We herein review outcomes of ureteral obstruction management in a single unit. Method Records of nephrostomy requests in Ysbyty Gwynedd between January 2017 and December 2021 were retrospectively reviewed. Information on patient demographics, primary pathology, performance status (PS), change in renal function and outcomes were recorded. Results Over 60 months, 102 nephrostomies were performed. Benign obstructions constituted 30.4% (n = 31) of cases. Of 71 cancer cases, 9 were re-insertions due to complications. Cancer group was associated with high and early deaths (11.3%, 64.5% and 85.5% at 3, 12 and 60 months, respectively) with only 1 in 5 kidney units illustrating improvement in renal function following decompression. All cancer patients were frail, with performance status of 2 (63%) and 3 (37%). Following nephrostomy insertion, 69.3% of kidney units developed urinary infection and/or sepsis requiring treatment. Only about 1 in 2 (53%) cancer patients received further oncological treatment (chemo- and /or radiotherapy). Though ante grade ureteric stenting was attempted in 23 kidney units following nephrostomy insertion for cancer, only 21 were successful and 2 of those blocked within 14 days. Conclusions Decompression of malignant ureteral obstruction may not improve survival and can involve multiple interventions with quality-of-life implication. Hence, the decision to decompress should not be the default and would therefore need to be individualized, adopting a multidisciplinary approach.

Modes of drainage of kidneys with bilateral malignant obstruction

Malignant ureteral obstruction (MUO) is an unpleasant finding resulting from a wide range of malignancies with limited survival prognosis. Its presentation and progression show that it can resist treatment with some stents, including single polymer ureteral stents. With most treatment failures, several treatments are available for the initial management and treatment of benign ureteral obstruction, including therapy with percutaneous nephrostomy (PCN), metallic stents, tandem stents, and other stents. Considering the variety of methods and the heterogeneous population of patients, evaluating the merit of each approach is challenging and needed. Due to the lack of significant studies in this field, these methods leave their performance up to the individual provider. This review aims to provide a framework for urologists to use for individual care and apply it appropriately to patients with MUO. Prospective clinical studies are needed to empower patients with MUO to receive evidence-based treatment and recommendations.

Unveiling the Challenges in Tandem Ureteral Stent Management for Malignant Ureteral Obstruction: Failure Rate, Risk Factors, and Durability of Their Replacement.

Malignant ureteral obstruction (MUO) is a sequela of advanced malignant disease that requires renal drainage, with tandem ureteral stents (TUSs) being a viable option. This study aimed to evaluate the TUS failure rate, associated risk factors, and the feasibility of replacing failed TUSs with a new pair of stents. A retrospective analysis of MUO patients treated with TUS insertion from 2014 to 2022 was conducted. TUS failure was defined as urosepsis, recurrent urinary tract infections, acute kidney failure, or new hydronephrosis on imaging. Cox proportional hazard regression analysis identified the independent predictors of TUS failure. A total of 240 procedures were performed on 186 patients, with TUS drainage failing in 67 patients (36%). The median time to failure was 7 months. Multivariate analysis revealed female gender (OR = 3.46, p = 0.002), pelvic mass (OR = 1.75, p = 0.001), and distal ureteral obstruction (OR = 2.27, p = 0.04) as significant risk factors for TUS failure. Of the failure group, 42 patients (22.6%) underwent TUS replacement for a new pair. Yet, 24 (57.2%) experienced a second failure, with a median time of 4.5 months. The risk factors for TUS second failure included a stricture longer than 30 mm (OR = 11.8, p = 0.04), replacement with TUSs of the same diameter (OR = 43, p = 0.003), and initial TUS failure within 6 months (OR = 19.2, p = 0.006). TUS insertion for the treatment of MUO is feasible and has good outcomes with a relatively low failure rate. Primary pelvic mass and distal ureteral obstruction pose higher risks for TUS failure. Replacing failed TUSs with a new pair has a success rate of 42.8%. Consideration should be given to placing larger diameter stents when replacing failed TUS.

Allium ureteral stent for the treatment of malignant ureteral obstruction: A median term study.

This study aimed to assess the safety and efficacy of Allium ureteral stents for the maintenance therapy of malignant ureteral obstruction (MUO). Clinical data of 25 patients (27 sides) with ureteral obstruction caused by a malignant tumor from December 2018 to December 2021 were retrospectively analyzed. Preoperative ultrasonography and computed tomography urography indicated hydronephrosis and MUO. Allium ureteral stents were placed using a retrograde or antegrade approach. Therapeutic effects and complications were recorded. The Wilcoxon signed-rank test was used to compare continuous variables between the preoperative and the last follow-up. A total of 25 patients (27 sides) were included in this study. After a follow-up time of 18 (11-29) months, the width of hydronephrosis [1.6 (1.0-2.2) cm vs 2.6 (1.2-3.3) cm, P = .000], glomerular filtration rate [83.8 (58.1-86.4) mL/minutes/1.73 m2 vs 74.5 (56.8-79.1) mL/minutes/1.73 m2, P = .001] and score of ureteral stent symptoms questionnaire [77 (76-79) vs 100 (98-103), P = .000] was significantly improved. Stent migration occurred in 3 of the 25 patients within 3 months after surgery. All patients with complications were followed up for at least 6 months after stent adjustment or exchange, and no other complications were found. Two patients died because of malignant complications. The stent patency rate was 88.9% (24/27) after the first operation, and 100% (27/27) after complications were treated. The Allium ureteral stent is safe and effective for the maintenance therapy of MUO, which can dramatically relieve the symptoms of patients. Stent migration is a major complication that can be resolved by endoscopic adjustment.

Evaluation of Renal Function and Stent Durability Following Resonance Stent Placement for Benign Disease.

Introduction: The metal-based Resonance stent (RS) has traditionally been placed in patients with malignant ureteral obstruction; as such, the long-term utility of RS among patients with benign ureteral obstruction (BUO) remains underinvestigated. Methods: We retrospectively reviewed our database for patients with BUO who underwent RS placement between 2010 and 2020. The impact of chronic RS placement on renal function was evaluated by estimated serum creatinine-based glomerular filtration rate (eGFR), furosemide renal scan, and CT-based renal parenchymal volume measurement. The number of and reason for RS stent exchanges during the follow-up period, incidence of encrustation, and the average indwell time were recorded. A cost analysis of placing the RS vs a polymeric stent was performed. Results: Among 43 RS patients with BUO, at a mean follow-up of 26 months, there was no change in eGFR (p = 0.99), parenchymal volume (p = 0.44), or split renal function of the stent-bearing side on renal scan (p = 0.48). The mean RS indwell time was 9.7 months. Eleven patients (26%) underwent premature stent replacement (6 cases) or removal (5 cases). Stents in 9 patients (32%) were encrusted, of which 4 (44%) required laser lithotripsy. Overall, 25 patients (58%) and 12 patients (28%) had a mean stent indwell time of ≥6 months and ≥12 months, respectively. Placing an RS resulted in a 52%, 37%, and 5.6% cost reduction compared with a regular polymeric stent placement, where it was exchanged every 6, 4, or 3 months, respectively. Conclusions: RS deployment in the patient with a BUO results in cost-effective maintenance of renal function and of renal parenchymal volume at a mean follow-up of 2 years; however, only 28% of patients fulfilled the 1-year criterion for RS indwell time.

The challenging management of malignant ureteral obstruction: Analysis of a series of 188 cases.

Malignant ureteral obstruction (MUO) is a common condition that complicates the course of advanced malignancies. The aims of this study are to analyze the causes, management, and survival of patients with obstructive nephropathy due to malignant ureteric obstruction and to determine prognostic factors. Furthermore, we studied the complications and outcomes in patients who underwent urinary diversion. A retrospective study was conducted on patients with computed tomography-confirmed MUO between January 2016 and November 2020. Demographic, clinical, radiological, laboratory, and management data were collected. Survival curves were estimated using the Kaplan-Meier method, and univariate and multivariate Cox proportional hazards models were used to test the association between parameters and survival. A total of 188 patients were included. The mean age was 69.01 years (SD, 14.95 years), and the majority (54.8%) were male. The most common mechanism leading to MUO was compression by a pelvic mass (36.9%), and the 3 most frequent tumors causing MUO were prostate (17.6%), bladder (16.5%), and rectal cancer (11.7%).Forty-seven patients (25%) underwent urinary diversion: 23 (48.9%) underwent double-J stenting and 21 (44.7%) underwent percutaneous nephrostomy. The most common reason for urinary diversion was acute kidney injury (53.3%). Recovery of renal function was observed in 55.8% of the patients after urinary diversion. The most frequently identified complications after urinary diversion were urinary tract infection (24.4%), hematuria (17.0%), and urinary sepsis (14.9%). The median survival after hydronephrosis diagnosis was 6.43 months (interquartile range, 1.91-14.81 months). In patients who underwent urinary decompression, the median survival after urinary diversion was 8.67 months (interquartile range, 2.99-17.28 months). In the multivariate analysis, a lower grade of hydronephrosis and cancer cachexia negatively impacted survival. Cancer patients with MUO have a poor prognosis; therefore, the risk-benefit ratio of urinary diversion should be carefully considered. Cachexia and hydronephrosis grade can be useful in selecting suitable candidates for urinary diversion.

MP42-09 FAILURE OF TANDEM URETERAL STENTS FOR MALIGNANT URETERAL OBSTRUCTION- WHAT'S NEXT?

You have accessJournal of UrologyCME1 Apr 2023MP42-09 FAILURE OF TANDEM URETERAL STENTS FOR MALIGNANT URETERAL OBSTRUCTION- WHAT'S NEXT? Orel Carmona, Asaf Shvero, Dorit E. Zilberman, Zohar A. Dotan, and Nir Kleinmann Orel CarmonaOrel Carmona More articles by this author , Asaf ShveroAsaf Shvero More articles by this author , Dorit E. ZilbermanDorit E. Zilberman More articles by this author , Zohar A. DotanZohar A. Dotan More articles by this author , and Nir KleinmannNir Kleinmann More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000003280.09AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: The success rate of drainage with tandem ureteral stents (TUS) for malignant ureteral obstruction (MUO) is 72-87%. Failure of TUS is usually followed by the insertion of a percutaneous nephrostomy tube (PCN). The objective of this study was to examine the possibility of replacing the first-time failed TUS with a new pair of TUS- the success rate of the procedure, and the risk factors for a second failure. METHODS: The medical records of all patients with MUO who underwent balloon dilation and TUS insertion in our institution between 2014-2022 were retrospectively analyzed. Failure of TUS was defined as an episode of urosepsis, recurrent urinary tract infections, acute kidney failure, or detection of new hydronephrosis on imaging scans. Independent risk predictors of failure of secondary TUS were determined by a multivariate cox regression analysis. RESULTS: 240 procedures were performed on 186 patients during the study period. 67 (36%) patients failed for the first time after a median follow-up time of 7 months (IQR 4-17). Of which, 25 (37.4%) patients were drained by a PCN, and 42 (62.6%) were treated by exchanging the TUS with a new pair. Among the patients who underwent a second TUS insertion, 18 (42.8%) did not fail again, and continued to enjoy timely replacements of the TUS. However, 24 (57.2%) patients did fail for the second time and were drained via PCN. In a multivariant analysis, we found that inserting the same diameter TUS as the pair that failed (p=0.002) and time to first failure ≤6 months (p=0.006) were significant risk factors for a second failure of TUS. Cox regression analysis found that distal ureteral stricture predicts shorter time to second failure. During the study period, the group that didn’t fail for a second time underwent 73 replacements of TUS overall (4±2.3 procedures per patient) in a median follow-up time of 19.5 months. CONCLUSIONS: The success rate of replacing TUS after its failure is 42.8%. When replacing failed TUS, one should consider larger-diameter stents. Source of Funding: None © 2023 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 209Issue Supplement 4April 2023Page: e570 Advertisement Copyright & Permissions© 2023 by American Urological Association Education and Research, Inc.MetricsAuthor Information Orel Carmona More articles by this author Asaf Shvero More articles by this author Dorit E. Zilberman More articles by this author Zohar A. Dotan More articles by this author Nir Kleinmann More articles by this author Expand All Advertisement PDF downloadLoading ...

MP42-11 SILICONE STENTING FOR CHRONIC URETERAL OBSTRUCTION IMPROVES STENT EXCHANGE FREQUENCY

You have accessJournal of UrologyCME1 Apr 2023MP42-11 SILICONE STENTING FOR CHRONIC URETERAL OBSTRUCTION IMPROVES STENT EXCHANGE FREQUENCY Bebe Eke and Suwaee, Ga Noah Canvasser Bebe EkeBebe Eke More articles by this author and Suwaee, Ga Noah CanvasserSuwaee, Ga Noah Canvasser More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000003280.11AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: Chronic ureter stenting is recommended for patients with malignant ureteral obstruction, or with benign ureteral obstruction but cannot tolerate or do not want definitive surgical management. Stents are exchanged at time intervals often limited by stent encrustation; prior in vitro studies have demonstrated that silicone stents have less encrustation. Our objective was to compare patients undergoing chronic exchanges with polymer-based and silicone stents. METHODS: This IRB-approved retrospective study included all adult patients who underwent chronic ureter stent exchange from August 2017 through August 2022. Patients were stented with either a Boston Scientific PercuflexTM Plus or a Cook Black Silicone stent. Demographics, dates of exchange, stent type and size, and the presence of external and luminal encrustation were captured from operative reports. A subset of patients with >8F stents was analyzed given larger stents have lower rates of encrustation. Students t-test and chi-squared analysis were used to compare polymer-based vs silicone stents. RESULTS: In total, 52 patients underwent 165 stent exchanges: 72% were polymer-based (n=119), 28% were silicone (n=44), and 1% were metallic (n=2, excluded). Table 1 lists patient demographics and stent sizes. Mean exchange interval for silicone stents was significantly longer than for polymer-based stents (197±60 vs 139±87 days, p<0.0001). Despite this, there was no significant difference in external encrustation (9 vs 18%, p=0.18) or luminal encrustation (7% vs 4%, p=0.49). Sub-group comparison of stents >8F also showed longer exchange interval (191±40 vs 106±36 days, p<0.0001), similar external encrustation (10.3 vs 24%, p=0.13), and similar luminal encrustation (6.9 vs 5.6%, p=0.82). CONCLUSIONS: Utilizing silicone stents for chronic ureter stent exchanges significantly increases the exchange interval due to lower encrustation rates over similar time periods compared to a polymer-based stent. Further work with other polymer-based and silicone stents is warranted to evaluate the generalizability of these results. Source of Funding: COI: Consultant for Boston Scientific and Cook Medical, this study is unfunded © 2023 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 209Issue Supplement 4April 2023Page: e571 Advertisement Copyright & Permissions© 2023 by American Urological Association Education and Research, Inc.MetricsAuthor Information Bebe Eke More articles by this author Suwaee, Ga Noah Canvasser More articles by this author Expand All Advertisement PDF downloadLoading ...

Serum creatinine trajectory after drainage of kidneys with bilateral malignant ureteral obstruction: a prospective non-randomized comparative study

BackgroundSerum creatinine trajectory (SCr-Tr) is a neglected prognostic tool for chronic and acute kidney injury. We aimed to assess the predictors of SCr-Tr during the time-to-nadir and serum creatinine (SCr) normalization rate after drainage, using percutaneous nephrostomy in patients with bilateral malignant ureteral obstruction.MethodsA prospective non-randomized study was performed on SCr-Tr in patients with bilateral malignant ureteral obstruction from August 2019 to March 2022. The primary outcome was SCr-Tr during the time-to-nadir.ResultsThis study included 102 patients with a mean age ± SD of 59.6 ± 14.7 years. SCr-Tr was non-linear with a mean ± SD (range) of 0.5 ± 0.4 (0.03–2.3) mg/dl/day. Multivariate analyses revealed that female gender (p = 0.016), body mass index (BMI; p = 0.005), and SCr at presentation (p < 0.001) were predictors of rapid SCr-Tr during the time-to-nadir. However, age (p = 0.008) and low urine output at presentation (p = 0.015) were associated with a lower SCr-Tr. In contrast, laterality of drainage (p = 0.544) and mean parenchymal thickness (p = 0.066) were not associated with mean SCr-Tr. Also, only the mean parenchymal thickness (p = 0.002) was a predictor of rapid SCr-Tr at ≥ 0.5 mg/dl/day. However, low BMI (p = 0.023) was associated with a high SCr normalization rate, while unilateral drainage (p = 0.045) was associated with a lower rate.ConclusionsFemale gender, low BMI, and SCr at presentation were predictors of rapid SCr-Tr during the time-to-nadir. Bilateral drainage was an independent predictor of SCr normalization rate, but not of rapid SCr-Tr. The mean parenchymal thickness was the only independent predictor for rapid SCr-Tr at ≥ 0.5 mg/dl/day.