Ureteral stents for malignant extrinsic ureteral obstruction: outcomes and factors predicting stent failure

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

OBJECTIVE

To 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/METHODS

The study cohort included OCa patients managed at our institution from 2004-2019 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.

RESULTS

Of 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% vs 85.1%; P = .79; all Clavian Grade I/II). Initial HN treatment failure occurred in 28 patients, predicted by renal atrophy (hazard ratios (HR) 3.27, P <.01). HN resolution occurred in only 52 (27%) patients and was predicted by lower International Federation of Gynecology and Obstetrics (FIGO) stage (FIGO III/IV HR 0.42, P <.01) and surgical tumor debulking/ureterolysis (HR 2.83, P = .02).

CONCLUSION

Resolution of HN associated with malignant obstruction from OCa is rare and is most closely associated with tumor debulking and International Federation of Gynecology and Obstetrics (FIGO) stage. Initial endoscopic treatment modality was not significantly associated with complications or resolution, though RUS failures were slightly more common. Ureteral reconstruction at time of debulking/ureterolysis is potentially underutilized.

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

Background

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.

Materials and methods

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.

Results

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.

Conclusions

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.

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

PURPOSE

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.

METHODS

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.

RESULTS

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® 6Fr metallic stent. The Resonance 6Fr metallic stent had the longest median functional duration of 14 months (p = 0.012).

CONCLUSION

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.

Prediction of Stent Failure for Malignant Ureteral Obstruction in Non-Urological Cancer

PURPOSE

To analyze prognostic factors associated with ureteral stent failure and to develop a prediction model for malignant ureteral obstruction (MUO) in patients with non-urological cancers.

MATERIALS AND METHODS

We retrospectively reviewed patients with non-urological cancers who underwent ureteral stenting or percutaneous nephrostomy (PCN) for MUO between 2006 and 2014. Variables predicting stent failure were identified using Cox regression analysis.

RESULTS

Of the 743 patients, 468 (63.0%) underwent ureteral stenting only, and 275 (37.0%) underwent PCN owing to technical (n=215) or functional (n=60) stent failure. The median overall survival was 4 [interquartile range (IQR) 1-11] months, and the median interval duration to stent failure was 2 (IQR 0-7) months. In univariate analysis, lower gastrointestinal cancer, previous radiotherapy to the pelvis, bladder invasion, lower ureteral obstruction, and low previous estimated glomerular filtration rate (eGFR) (<30 mL/min/1.73 m²) were significantly associated with a decreased survival rate. In multivariate analysis, bladder invasion and previous eGFR were significant predictors. With these two predictors, we divided patients into three groups based on their presence: low-risk (neither factor; n=516), intermediate-risk (one factor; n=206), and high-risk (both factors; n=21). The median stent failure-free survival rates of patients in the low-, intermediate-, and high-risk groups were 26 (8-unreached), 1 (0-18), and 0 (0-0) months, respectively (p<0.001).

CONCLUSION

In cases of ureteral obstruction caused by non-urological cancers, patients with bladder invasion and a low eGFR showed poor stent failure-free survival. Therefore, PCN should be considered the primary procedure for these patients.

Effect of ureteral stent length and implantation position on migration after implantation

BACKGROUND

Ureteral obstruction is a urinary system disease that causes urinary retention, renal injury, renal colic, and infection. Ureteral stents are often used for conservative treatment in clinics, and their migration usually results in ureteral stent failure. The migrations include proximal migration to the kidney side and distal migration to the bladder side, but the biomechanism of stent migration is still unknown.

METHOD

Finite element models of stents with lengths from 6-30 cm were developed. The stents were implanted into the middle of the ureter to analyze the effect of stent length on its migration, and the effect of stent implantation position on 6-cm-long stent migration was also observed. The stents' maximum axial displacement was used to assess the ease of stent migration. A time-varying pressure was applied to the ureter outer wall to simulate peristalsis. The stent and ureter adopted friction contact conditions. The two ends of the ureter were fixed. The radial displacement of the ureter was used to evaluate the effect of the stent on peristalsis.

RESULTS AND DISCUSSION

The maximum migration occurs in the positive direction for a 6-cm-long stent implanted at the proximal ureter (CD and DE), but in the negative direction at the distal ureter (FG and GH). The 6-cm-long stent demonstrated almost no effect on ureteral peristalsis. The 12-cm-long stent diminished the radial displacement of the ureter from 3-5 s. The 18-cm stent diminished the radial displacement of the ureter from 0-8 s, and the radial displacement within 2-6 s was weaker than other time. The 24-cm stent diminished the radial displacement of the ureter from 0-8 s, and the radial displacement within 1-7 s was weaker than other time.

CONCLUSION

The biomechanism of stent migration and ureteral peristalsis weakening after stent implantation was explored. Shorter stents were more likely to migrate. The implantation position had less influence on ureteral peristalsis compared with the stent length, which provided a reference for stent design aimed at reducing stent migration. Stent length was the main factor affecting ureteral peristalsis. This study provides a reference for the study of ureteral peristalsis.

Hydronephrosis in patients with cervical cancer: An improved stent-change therapy for ureteral obstruction Stent-change for ureteral obstruction in cervical cancer

OBJECTIVE

Ureteral stent replacement is a routine treatment for hydronephrosis in patients with cervical cancer. We developed an improved ureteral stent-change operation for hydronephrosis in cervical cancer patients and compared its outcomes with traditional stent change procedures.

STUDY DESIGN

Clinical data of hydronephrosis in cervical cancer patients who were admitted to our hospital from August 2014 to October 2019 were analyzed. We retrospectively reviewed 131 cervical cancer patients, out of which 43 cases included patients in the improved operation group, whereas 88 patients with hydronephrosis followed the traditional ureteral stent-change operation for ureteral obstruction. The outcomes of the two procedures were compared using the propensity score matching method.

RESULTS

As opposed to the traditional ureteral stent change strategy, the patients in the improved group required shorter operation time (p = 0.001) and higher success rate (p = 0.004). The FIGO stage (p = 0.046), the level of ureteral obstruction (p = 0.027), radiotherapy history (p = 0.01), stent replacement times (≤2times or > 2times) (p = 0.001), and serum creatinine level (≤200 μmol/L or > 200 μmol/L) (p < 0.001) were significantly different between the two groups before propensity score matching. Propensity score matching analysis was used to eliminate the clinical differences of 43 patients in the traditional group; however, the span of visual hematuria during the surgical complications was not included (p = 0.026) in the results.

CONCLUSION

An improved ureteral stent change operation is an advanced treatment option for cervical cancer patients suffering from hydronephrosis. In contrast to traditional ureteral stent change techniques, our developed strategy lowers complications such as visual hematuria but improves the success.

Acute kidney injury due to bilateral malignant ureteral obstruction: Is there an optimal mode of drainage?

There is a well-known relationship between malignancy and impairment of kidney functions, either in the form of acute kidney injury or chronic kidney disease. In the former, however, bilateral malignant ureteral obstruction is a surgically correctable factor of this complex pathology. It warrants urgent drainage of the kidneys in emergency settings. However, there are multiple controversies and debates about the optimal mode of drainage of the bilaterally obstructed kidneys in these patients. This review addressed most of the concerns and provided a comprehensive presentation of this topic from the recent literature. Also, we provided different perspectives on the management of the bilateral obstructed kidneys due to malignancy. Despite the frequent trials for improving the success rates and functions of ureteral stents, placement of a percutaneous nephrostomy tube remains the most recommended tool of drainage due to bilateral ureteral obstruction, especially in patients with advanced malignancy. However, the disturbance of the quality of life of those patients remains a major unresolved concern. Beside the unfavorable prognostic potential of the underlying malignancy and the various risk stratification models that have been proposed, the response of the kidney to initial drainage can be anticipated and evaluated by multiple renal prognostic factors, including increased urine output, serum creatinine trajectory, and time-to-nadir serum creatinine after drainage.

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.

Management and outcomes of hydronephrosis in patients with metastatic extramammary Paget's disease: A retrospective analysis

Hydronephrosis in extramammary Paget's disease (EMPD) with distant metastasis (metastatic EMPD) has been observed in medical practice; however, its prognosis remains unclear. Retrospective analyses were performed to assess the management and outcomes of hydronephrosis in metastatic EMPD. During a follow-up of 44 patients with metastatic EMPD, 13 (30%) developed hydronephrosis. Ten (77%) of the 13 patients with hydronephrosis had impaired renal function (estimated glomerular filtration rate: <60 ml/min/1.73 m² ), and ureteral stents were placed in every patient with impaired renal function. The stent was placed successfully in all 10 patients, and their renal function recovered within a median period of 7 days. Importantly, each of these patients continued chemotherapy, and none of them experienced stent failure. The median overall survival time (OS) in patients with metastatic EMPD and hydronephrosis (n = 13) was 7.8 months. Treatment for hydronephrosis was not a significant factor for OS, and median OS in patients who underwent ureteral stent replacement (n = 10) was 14.7 months. Collectively, our results indicate that hydronephrosis is relatively common, and ureteral stent placement should be considered in cases of metastatic EMPD with hydronephrosis to maintain renal function and continue chemotherapy toward a better prognosis.

Antegrade placement of JJ catheter in the treatment of malignant ureteral obstruction: Retrospective analysis of a single centre

OBJECTIVE

The aim of the present study was to examine the results of antegrade JJ stent placement in upper urinary tract obstruction in patients where retrograde placement was not possible.

METHODS

In this retrospective study, patients who underwent antegrade JJ stent placement for malignant ureteral obstruction in the urology clinic of a university hospital between January 1, 2018 and December 31, 2020 were included in the study. JJ stent was placed under local or general anaesthesia guided by ultrasonography and fluoroscopy. Age, gender, kidney function values, pathologies causing obstruction, and complications of the patients were examined.

RESULTS

In this study, 40 patients (16 men, 24 women) who underwent antegrade JJ stent placement were included. The mean ages of the women and men included were 51 (31-91) years and 62.5 (26-81) years, respectively. In all, antegrade JJ stenting was performed in 61 renal units of these patients. Of these, 21 were bilateral, 11 in the right collecting system and 8 in the left collecting systems. Clinical and technical success was achieved in 59 of the 61 procedures (96.6%). Arteriovenous fistula developed in only one patient, whereas no serious complications such as massive bleeding, resistant hematuria or pseudoaneurysm occurred in the remaining patients. The procedure was completed in a mean time of 15-30 minutes.

CONCLUSIONS

Antegrade JJ stent placement is a procedure with a high success rate and low risk of complications that can be used in patients with severe ureteral obstruction owing to malignant or benign aetiologies. This method should be applied in centres experienced in malignant ureteral obstruction and on patients where retrograde placement was not possible. Furthermore, it should be considered as an alternative treatment option to open surgery as it can be performed under local anaesthesia in patients at a high risk of anaesthesia.

Longitudinal Outcomes from Conservative Management of Cervical Cancer Associated Ureteral Obstruction

OBJECTIVE

To identify predictors of hydronephrosis (HN) resolution and HN treatment failure. HN is a common comorbid condition with cervical cancer (CCa). Treatments for CCa continue to improve and long-term management strategies of HN are becoming increasingly necessary.

METHODS

A query of a single hospital (2004 - 2019) ICD-9 and CPT codes was made to develop a cohort of CCa patients with HN. A retrospective review was performed. The effects of patient, renal/HN, and cancer covariates on time to HN treatment failure, treatment complications and time to HN resolution were evaluated using logistic regression and competing risk Cox regression models.

RESULTS

Of the 1670 women treated for CCa during the study period, 179 (10.7%) developed HN (n = 72 (40%) bilateral), 78 (44%) at time of CCa diagnosis and 101 (56%) as a result of treatment, of which 145 (81%) underwent initial treatment with a PCN (n = 77, 53%) or US (n = 68, 47%). Complication rates were similar between PCN (56%) and US (61%) when adjusting for treatment time. Initial treatment failure was more likely with US vs PCN (HR 3.2, P <0.01). HN resolution (n = 32, 22%) without reconstruction was predicted by HN concurrent with CCa diagnosis (HR 3.1, P <0.01) and bilateral HN (HR 0.2, P <0.01).

CONCLUSION

CCa associated HN has a resolution rate of only 19% at 12 months. Those presenting with HN after CCa treatment are less likely to resolve without reconstruction. PCN and US have similar complication rates but initial US placement has a nearly three times increased risk of failing than PCN.

Clinical factors predicting ureteral stent failure in patients with external ureteral compression

Double-J stent (DJ) placement is usually the treatment of choice for relieving external compression of the ureter. However, in some cases DJ function may become impaired and a percutaneous nephrostomy (PCN) may be required. Previous studies have reported different predictive factors for choosing PCN or DJ insertion as the initial treatment. In this study, we analyzed the risk factors for DJ failure in patients with external ureteral compression. Our results showed that the patients with moderate and severe hydronephrosis (p-value = 0.0171 and 0.0249, respectively), preexisting pyuria (p-value = 0.0128), or lower ureter obstruction (p-value = 0.0305) were more prone to DJ laterality. Age was also an important predictor. Urologists should pay more attention to these patients and consider PCN as the initial treatment.

Predictors of antegrade ureteral stenting failure: a single-center experience in patients with malignant and benign ureteral obstruction

OBJECTIVE

To determine the potential predictors of antegrade ureteral stenting (AUS) failure in patients with malignant and benign ureteral obstruction.

METHOD

We retrospectively evaluated 116 AUS procedures performed in 80 patients for ureteral obstruction due to malignant and benign causes. Variables such as etiology for obstruction, ureter shape, previous treatment regimen, history of ileal loop diversion, and presence of percutaneous nephrostomy were recorded. Univariate and multivariate logistic regression methods were used between these variables and stent failure.

RESULTS

Antegrade ureteral stenting was performed as single stage in 24 procedures (n: 24/116, 21%) and performed as a two-step approach after percutaneous nephrostomy in 92 procedures (n: 92/116, 79%). Ureteral stent was successfully deployed in 112 AUS procedures (n: 112/116, 96.5%). In 35 of these successful procedures, the patients were referred to our department due to prior failed retrograde ureteral stenting (RUS). Subsequent stent failure occurred in 40 procedures after a median interval of 39 days. Pre-stenting percutaneous nephrostomy (PN) was a statistically significant risk factor for stent failure (p: 0.041), and age showed an inverse relationship with stent failure (p: 0.008). Complications in early (within the first 30 days after procedure) and late stage occurred in a total of 17 procedures. Early complications included urinary tract infection (n: 11), stent migration (n: 3), and malposition (n: 1). Late complications (after 30 days) were urinary tract infection (n: 1) and stent migration (n: 1).

CONCLUSION

This study suggests that AUS can be performed effectively in both benign and malignant ureteral obstructions including cases with prior failed RUS. Two-step AUS after percutaneous nephrostomy was found to be a significant risk factor for subsequent stent failure in our study cohort.

Kidney injury and disease in patients with haematological malignancies

Acute kidney injury (AKI) is common in patients with cancer, especially in those with haematological malignancies. Kidney injury might be a direct consequence of the underlying haematological condition. For example, in the case of lymphoma infiltration or extramedullary haematopoiesis, it might be caused by a tumour product; in the case of cast nephropathy it might be due to the presence of monoclonal immunoglobulin; or it might result from tumour complications, such as hypercalcaemia. Kidney injury might also be caused by cancer treatment, as many chemotherapeutic agents are nephrotoxic. High-intensity treatments, such as high-dose chemotherapy followed by haematopoietic stem cell transplantation, not only increase the risk of infection but can also cause AKI through various mechanisms, including viral nephropathies, engraftment syndrome and sinusoidal obstruction syndrome. Some conditions, such as thrombotic microangiopathy, might also result directly from the haematological condition or the treatment. Novel immunotherapies, such as immune checkpoint inhibitors and chimeric antigen receptor T cell therapy, can also be nephrotoxic. As new therapies for haematological malignancies with increased anti-tumour efficacy and reduced toxicity are developed, the number of patients receiving these treatments will increase. Clinicians must gain a good understanding of the different mechanisms of kidney injury associated with cancer to better care for these patients.

A novel risk classification score for malignant ureteral obstruction: a multicenter prospective validation study

Emergence of malignant ureteral obstruction (MUO) has been reported as a sign of poor prognosis; however, the distribution of survival time in patients with MUO is considerably wide, and no risk classification score has been constructed. To evaluate whether a novel risk classification score for overall survival that we previously developed, is effective in a large cohort. Investigator-initiated, prospective, multicenter diagnostic/prognostic study was conducted. Patients with MUO were divided into three risk groups based on the score calculated using four prognostic factors (PLaCT: Primary site, Laterality, serum Creatinine level, and Treatment for primary site) at the first visit, and prospective follow-up was performed. Overall survival and ureteral stent failure-free survival of each risk group were compared. In total, 300 patients with 21 different primary sites were enrolled. The numbers of patients in good, intermediate, and poor risk groups were 105, 106, and 89, respectively. Median survival times of patients in good, intermediate, and poor risk groups were 406, 221, and 77 days, respectively (P < 0.0001). In 217 patients with ureteral stenting, median ureteral stent failure-free survival times of good, intermediate, and poor risk groups were 385, 183, and 57 days, respectively (P < 0.0001). Limitations include the limited ethnicity and the extended duration of study enrollment. The novel PLaCT risk classification score could divide MUO patients into three risk groups with distinct survival times and ureteral stent patencies. This score will aid in establishing prognosis and treatment strategy for all physicians engaged in cancer treatment.

Predictors for failure of endoscopic ureteric stenting in patients with malignant ureteric obstruction: systematic review and meta-analysis

OBJECTIVE

To determine the factors for failure of endoscopic ureteric stenting in patients with malignant ureteric obstruction.

METHODS

We performed a search strategy in the Medical Literature Analysis and Retrieval System Online (MEDLINE), the Excerpta Medica dataBASE (EMBASE), the Literatura Latino-Americana e do Caribe em Ciências da Saúde database (LILACS), and the Cochrane Central Register of Controlled Trials (CENTRAL) databases. We included patients with malignant ureteric obstruction, who had a JJ catheter insertion. The studies reported the percentage of failure and risk factors, e.g. bladder invasion or deformity of the trigone, hydronephrosis, renal failure, previous radiotherapy, age, obstruction aetiology, and patient's health status. We performed a meta-analysis using R software ('meta' and 'metafor' libraries).

RESULTS

We included nine studies that met the inclusion criteria, with 761 patients and an average age of 60.5 years. The studies assessed the time to failure during the first 30 days. The reported failure rate was 32% (95% confidence interval [CI] 21-45%; I² = 88%). Regarding risk factors for failure, bladder invasion or deformity of the trigone had a hazard ratio (HR) of 4.8 (95% CI 1.28-8.5; I² = 97.4%); severe hydronephrosis had a HR of 3.92 (95% CI 0.32-7.52; I² = 93.9%); and age <65 years had a HR of 0.93 (95% CI 0.8-0.9; I² = 0%).

CONCLUSIONS

We found a high probability of failure for endoscopic urinary decompression in patients with malignant ureteric obstruction. Factors such as bladder invasion or deformity of the trigone and age >65 years had an increased risk of failure.

Estimation of successful capping with complete aspiration of bladder via nephroureterostomy tube

BACKGROUND

Ureteral stent and nephroureterostomy tube (NUT) are treatments of ureteral obstruction. Ureteral stent provides better quality of life. Internalization of NUT is desired whenever possible.

AIM

To assess outcomes of capping trial among cancer patients with complete aspiration of retained contrast from bladder via NUT.

METHODS

Our Institutional Review Board approved retrospective review of all NUT placement, NUT exchange and conversion of nephrostomy catheter into NUT performed during June 2013 to June 2015 (n = 578). Cases were excluded due to lack of imaging of bladder (n = 37), incomplete aspiration of bladder (n = 324), no attempt at capping NUT (n = 166), and patients with confounding factors interfering with results of capping trial including non-compliant bladder, bladder outlet obstruction and catheter malposition (n = 14). Study group consisted of 37 procedures in 34 patients (male 19, female 15, age 2-83 years, average 58, median 61) most with cancer (prostate 8, endometrial 5, bladder 4, colorectal 4, breast 2, gastric 2, neuroblastoma 2, cervical 1, ovarian 1, renal 1, sarcoma 1, urothelial 1 and testicular 1) and one with Crohn’s disease. Medical records were reviewed to assess outcomes of capping trial. Exact 95% confidence intervals (95%CI) were calculated.

RESULTS

Among patients with complete aspiration of retained contrast, 30 (81%, 95%CI: 0.65-0.92) catheters were successfully capped (range 12-94 d, average 40, median 24.5) until planned conversion to internal stent (23), routine exchange (5), removal (1) or death unrelated to catheter (1). Seven capping trials (19%, 95%CI: 0.08-0.35) were unsuccessful (range 2-22 d, average 12, median 10) due to leakage (3), elevated creatinine (2), fever/hematuria (1) and nausea/vomiting (1).

CONCLUSION

Capping trial success among patients with complete aspiration of retained contrast/urine from bladder via NUT appears high.

Long-Term Follow-Up of Yearly Replaced Double Internal Stents for Extrinsic Malignant Ureteral Obstruction

Introduction: To assess long-term outcomes of double internal stents (DIS) for the relief of external malignant ureteral obstruction (MUO). Materials and Methods: DIS (7F each; 12-month indwelling time) were inserted under general anesthesia in 62 consecutive patients (75 renal units) with MUO during 2007-2018. Surveillance was performed every 3 months, and stents were exchanged routinely every year. The need for permanent stent retrieval was considered stent failure. Maintenance of stent patency and disease-specific survival (DSS) were estimated (Kaplan-Meier). Risk factors were also assessed (univariate and multivariable Cox regression analyses). Results: The median follow-up was 27 months (interquartile range [IQR] 20-27). The most frequent tumors causing obstruction were colorectal and ovarian cancers. Six patients (10%) had stent failure caused by sepsis, creatinine elevation, or hematuria. The average time to failure was 15 months (range 1-27). A history of radiation and an estimated glomerular filtration rate (eGFR) ≤45 mL/(min/1.73 m²) were associated with stent failure (p = 0.038 and p = 0.001, respectively). Thirty-nine patients died with a median DSS of 21 months (IQR 8.6-not reached). Multivariate analysis identified eGFR ≤60 mL/(min/1.73 m²) (hazard ratio [HR] 2.1, 95% confidence interval [CI] 1.1-4.2, p = 0.02) and need for balloon dilation (HR 2.1, 95% CI 1.1-4.1, p = 0.02) as independent predictors for disease-related mortality. Twenty-six patients (42%) had stent-related complications, for example, irritative symptoms, hematuria, and infections, of whom only two failed. Conclusions: One-year indwelling DIS provide effective long-term relief of MUO and represent a simple and effective alternative to other methods of urinary diversion. They avoid the need for external tubes and contribute to improved patient satisfaction.

Percutaneous nephrostomy in obstructing pelvic malignancy does not facilitate further oncological treatment

OBJECTIVE

The optimal management of patients with ureteric obstruction in advanced malignancy is unclear. How quality of life is affected by a nephrostomy and how many of these patients undergo further oncological treatment remains uncertain. The objective of this retrospective multicentre study was to look at the outcomes of patients who had percutaneous nephrostomy insertion for malignancy.

METHODS

We identified patients who had a nephrostomy inserted for ureteric obstruction due to malignancy at our institution from January 2015 to December 2018. We obtained data retrospectively from our electronic patient record system. Patients who had nephrostomy insertion for other causes such as ureteric calculi or injury were excluded from the study.

RESULTS

105 patients underwent nephrostomy insertion during this time interval. 51.42% patients (n = 54) had urological malignancies (bladder and/or prostate cancer). The median LOS was 14 days (range 1-104 days) post-procedure and 39.04% (n = 41) had at least one 30-day readmission to hospital. The average starting creatinine level was 348 mmol/L (range 49-1133) and the average creatinine at discharge was 170 mmol/L (range 44-651). Although the average change in the creatinine (190 mmol/L) is statistically significant (p < 0.001), it did not seem to prolong life of the patients. Only 26 (24.76%) patients were alive (all-cause mortality) at the end of the 4-year period with an average life expectancy of 139 days following nephrostomy. Only 30.47% (n = 32) patients underwent further oncological treatment.

CONCLUSION

In our series, most patients who had nephrostomy insertion for ureteric obstruction due to malignancy had no further oncological treatment following insertion. Percutaneous nephrostomy is a procedure not without associated morbidity and does not always prolong survival. Due to the poor prognosis in cases of advanced malignancy, we advocate multi-disciplinary decision-making prior to nephrostomy insertion.

Placement of double-J stent in patients with malignant ureteral obstruction: antegrade or retrograde approach?

AIM

To determine whether antegrade or retrograde methods should be preferred for double-J stent placement in patients with malignant ureteral obstruction (MUO).

MATERIAL AND METHODS

The medical records of patients treated for MUO in the Urology and Interventional Radiology Clinic, Konya Training and Research Hospital, were reviewed retrospectively. Patients with benign aetiology were excluded from the study. Reports of the procedures, ultrasonography findings, computed tomography (CT), angiography, and pyelography images and the follow-up records of patients with MUO were assessed. A total of 111 patients and 114 ureteral stenting treatments were included in the study; 63 (55.3%) were operated on using the antegrade ureteral stenting (AUS) method, whereas 51 (44.7%) were operated on using the retrograde ureteral stenting (RUS), method, and the characteristics of these groups were evaluated. The presence of hydroureteronephrosis and ureteral tortuosity were determined.

RESULTS

Overall success rates were found to be 95.2% using the AUS method and 47.1% using the RUS method. The technical success of the antegrade method was significantly higher in patients with or without tortuosity (respectively: p=0.005, Z shape p=0.001, pigtail shape p=0.035″). The technical success of the antegrade method was significantly higher in patients with hydroureteronephrosis (p=0.001).

CONCLUSION

The AUS technique should be the first choice for double-J stent placement in patients with MUO.