Management of ureteral obstruction secondary to pelvic malignancies

Effect of emergent nephrostomy on long-term total and split renal function in patients with upper urinary tract obstruction due to pelvic malignant tumors

PURPOSE

This study aimed to investigate the impact of nephrostomies on the outcome of total renal function (TRF) and split renal function (SRF) in patients with malignant pelvic tumors associated with upper urinary tract obstruction (UUTO).

METHODS

Patients with pelvic tumors suffering severe unilateral hydronephrosis treated at our hospital from 2000 to 2022 were included. Data for nephrostomy placement, short- and long-term renal function, and radiological and nuclear imaging studies were collected. The TRF and SRF of patients who underwent nephrostomy were compared to those who did not.

RESULTS

Seven patients were included (rhabdomyosarcoma: 5, ovarian germ cell tumor: 1, malignant rhabdoid tumor: 1). Nephrostomies were placed in four, which were successfully managed without severe infections. Estimated glomerular filtration rate (eGFR) was significantly improved at the end of treatment in patients with nephrostomy. In contrast, eGFR in patients who did not undergo nephrostomy was not improved. Nuclear imaging studies (renograms or renal scintigrams) revealed impaired SRF of the affected kidney compared to the contralateral kidney, even in patients whose eGFR was within normal levels. Notably, SRF showed a trend to improve over time in one patient treated with nephrostomy.

CONCLUSION

Nephrostomy for UUTO caused by pelvic tumors may improve renal outcome.

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.

Which is the best way for patients with ureteral obstruction? Percutaneous nephrostomy versus double J stenting

BACKGROUND

Percutaneous nephrostomy (PCN) and Double J stenting (DJS) are the 2 main treatment options of ureteral obstruction. We evaluate which of these 2 methods is superior concerning the course of procedure, postoperative complication and quality of life.

METHODS

A detailed review of electronic databases including PubMed, Embase, Cochrane Library, China Biology Medicine disc, China National Knowledge Infrastructure up to February 21st, 2021 was searched. Continuous data were evaluated using mean difference (MD) with 95% confidence interval (CI), while nominal data were analyzed by risk ratio (RR) with 95% CI. Meanwhile, we performed the subgroup analysis based on study design, disease type, sample size, sepsis, DJ diameter, nephrostomy diameter, anesthesia type and guidance under X-ray or ultrasound.

RESULTS

There were 18 previous studies included in current study. As a result, we found that there were significant differences in fluoroscopy time (MD = 0.31; 95% CI, 0.14-0.48, P < .001) and hospital stay (MD = 1.23; 95% CI, 0.60-1.85, P < .001). However, no statistic difference was detected in operative time (MD = 5.40; 95% CI, -1.78 to 12.58, P = .140) between the paired groups. Although DJS showed a higher rate of postoperative complications (25.19% vs 17.61%), there was no significant difference in the incidence of complications following DJS and PCN (RR = 0.92; 95% CI, 0.60-1.43; P = .720). Based on the EuroQol analysis, the 2 main treatment options had different impacts on quality of life. The pooled results showed that PCN patients reported more difficulties in self-care compared to DJS patients (RR = 3.07; 95% CI, 1.32-7.14; P = .009).

CONCLUSIONS

DJS is a safe and better method of temporary urinary diversion than PCN for management of ureteral obstruction with shorter fluoroscopy time and hospital stay. As for quality of life, patients receiving PCN had a distinct difficulty in self-care compared to those receiving DJS. However, these 2 treatment options often depends on the individual situation.

A Silicone-Covered Self-Expanding Metal Stent with Anti-migration Features for Treating Malignant Ureteral Obstruction

PURPOSE

To evaluate the effectiveness and safety of the Urexel stent for treating malignant ureteral obstruction (MUO).

MATERIALS AND METHODS

This retrospective study included 129 patients (mean age: 57.9 ± 11.8 years; men: n = 64, 49.6%; ureteral units [UUs]: N = 175) who underwent Urexel stent placement to treat MUO between March 2013 and April 2021. The Urexel stent is a fully covered self-expanding metal stent. To reduce stent migration, the proximal end of the stent has an additional layer of stent mesh and is flared mildly.

RESULTS

Eighty-three patients (64.3%) had unilateral MUO (right side: n = 47, 36.4%; left side: n = 36, 27.9%), and 46 patients (35.7%) had bilateral MUO. Successful Urexel stent placement after successful guidewire passage of the obstructed ureteral segment was achieved in 172 UUs, rendering a technical success rate of 98.3%. Stent malfunction occurred in 37 UUs (21.4%) during follow-up, including tumor overgrowth (n = 29), tumor ingrowth (n = 3), stent migration (n = 3), and stent collapse (n = 2). A total of 120 patients (93.0%) died during a median follow-up of 4.1 months (range: 0.2 - 33.5). The median survival of the patients was 4.4 months (interquartile range [IQR] 2.0 - 8.8). The median malfunction-free survival of the patients was 3.6 months (IQR: 1.6 - 7.9). Fifteen grade 3 or higher complications occurred in 14 patients (10.9%), including flank pain (n = 10), gross hematuria (n = 4), and dysuria (n = 1).

CONCLUSION

Urexel stent placement may be effective and safe for treating MUO.

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 Outcomes After Urinary Diversion for Malignant Ureteral Obstruction Secondary to Non-urologic Cancer: An Analysis of 778 Cases

BACKGROUND

This study investigated patient outcomes after urinary diversion in order to manage malignant ureteral obstruction caused by non-urologic cancers and to evaluate predictive factors for overall survival.

METHODS

The study retrospectively reviewed patients with non-urologic malignancies who underwent ureteral stenting or percutaneous nephrostomy for ureteral obstruction between 2006 and 2014. The variables for predicting overall survival were identified by Cox regression analysis.

RESULTS

The study enrolled 778 patients, including 522 patients who underwent ureteral stenting and 256 patients who underwent percutaneous nephrostomy. Renal function was assessed immediately and then 2 weeks after urinary diversion. The median survival period was 5 months (interquartile range [IQR] 2-12 months). A total of 708 patients died. The patients who received chemotherapy after urinary diversion had a survival gain of 7 months compared with the patients who did not receive subsequent chemotherapy (p < 0.001). The survival rate did not differ between the various types of urinary diversion (p = 0.451). In the multivariate analysis, lower survival rates were significantly associated with male sex; previous chemotherapy without radiotherapy; an increasing number of events related to malignant dissemination; low preoperative hemoglobin (< 10 mg/dL), albumin (< 3 g/dL), and estimated glomerular filtration (< 60 mL/min/1.73 m²) rates; and no subsequent chemotherapy or radiotherapy.

CONCLUSIONS

In cases of ureteral obstruction caused by non-urologic malignancies, the overall survival was poor. However, the patients who received chemotherapy after urinary diversion had a survival gain of 7 months. Therefore, urinary diversion could be considered to preserve renal function for subsequent chemotherapy, whereas patients with the poor prognostic factors should be presented with the option of no intervention.

Role of Preoperative Ureteric Stenting in Optimization of Patients with Retroperitoneal Tumors Associated with Obstructive Uropathy

Retroperitoneal tumors can cause ureteric obstruction leading to obstructive uropathy. Early preoperative ureteric stenting helps to improve renal function and also helps in identifying ureters and prevent ureteric injury during surgery. This study was aimed at assessing the outcome of preoperative stenting in optimizing such patients. A total of 24 cases were enrolled. Of these, 15 patients who had obstructive uropathy were taken for ureteric stenting preoperatively and other 9 patients have undergone surgery without stenting. Twelve patients were stented successfully but 3 patients could not be stented (underwent percutaneous nephrostomy). All 24 patients underwent laparotomy, and of the 12 stented patients, 11 underwent successful resection and one had unresectable tumor. The patient's serum creatinine was assessed initially and then twice after stenting (48 h and 5 days). Serum creatinine was also estimated 24 h after excision of the tumor. In the successfully stented and operated patients, mean initial creatinine was 7.85. The mean creatinine at 48 h and 5 days after stenting was 4.29 and 1.19 respectively. The mean creatinine 24 h after resection of the tumor was 1.04. Of the non-stented patients, 3 had ureteric injury during surgery. We conclude that preoperative ureteric stenting is helpful for optimization of patients with retroperitoneal tumors with obstructive uropathy.

Antegrade insertion of a double J catheter in the treatment of malignant ureteral obstruction: a retrospective analysis of the results obtained with a modified technique at a university hospital

OBJECTIVE

To analyze the results obtained with a modified antegrade double J catheter insertion (JJ stenting) technique in patients with urinary tract obstruction due to malignancy.

MATERIALS AND METHODS

This was a retrospective analysis of data collected from patients undergoing antegrade JJ stenting for malignant ureteral obstruction in the interventional radiology department of our institution between March 1, 2017 and May 31, 2019.

RESULTS

Antegrade JJ stenting was performed in 32 patients (20 women and 12 men). The mean age was 66.2 years among the females and 61.5 years among the males. A total of 53 antegrade JJ stenting procedures were performed. The procedure was successful in 50 cases and failed in 3 (due to migration of the double J catheter in 2 and due to technical failure in 1). Complications occurred in 3 patients (low back pain, in 1, subcapsular hematoma, in 1, and pyelonephritis, in 1). The procedure time ranged from 14 min to 55 min.

CONCLUSION

In patients with ureteral obstruction due to malignancy, antegrade JJ stenting is safe and effective. The technique selected in our study is easily reproduced and can be performed by a trained professional.

The resonance® metallic ureteral stent in the treatment of malignant ureteral obstruction: a prospective observational study

Background

To study the outcomes and experiences of using metallic stents in treating patients with malignant ureteral obstruction (MUO), we examined the effects of metallic ureteral stenting using the Cook Resonance® stent in the treatment of MUO.

Methods

All patients who had a Resonance metallic stent inserted between April 2015 and March 2018 at one of multiple facilities were prospectively observed with a 1-year follow-up. The primary outcome was the patency rate of the metallic ureteral stent. The secondary outcomes included the complications (e.g., infection and fever).

Results

Although stent insertion was attempted in 50 patients, the stent could not be inserted as a ureteral stent in three patients due to severe ureteral stricture, and one ureteral cancer patient was excluded from the analysis. The remaining 46 patients’ median age was 67 years (range 28–85 years) (16 males, 30 females). Twenty-four patients died during the study; their median survival time was 226 days. The median follow-up period for the censored patients was 355 days (range 16–372 days), and just seven patients were still alive without Resonance failure > 1 year later. The women’s IPSS scores tended to be lower than those of the men. Regarding the OABSS score, although the women’s total score tended to be low, the difference between the men’s and women’s scores was nonsignificant. The bacteria detected from urine culture after stent insertion were more gram-positive than gram-negative.

Conclusion

Metallic ureteric stenting using the Resonance stent is safe and effective for treating MUO. Subjective symptoms were relatively less in the female patients.

Comparison of single and tandem ureteral stenting for malignant ureteral obstruction: a prospective study of 104 patients

OBJECTIVES

The aim of this study was to compare single and tandem ureteral stenting in the management of malignant ureteral obstruction (MUO).

METHODS

Our hospital's institutional review board approved this prospective study. Between November 2014 and June 2017, single ureteral stenting was performed in 56 patients (94 renal units) and tandem ureteral stenting in 48 patients (63 renal units) for MUO. A comparative analysis of the technical success rate, patient survival, stent patency, and complications was performed.

RESULTS

Similar demographic data were observed in patients receiving either single or tandem ureteral stenting. The technical success rate was 93.6% (88/94) for single ureteral stenting and 95.2% (60/63) for tandem ureteral stenting. There was no difference in overall survival between patients receiving single or tandem ureteral stenting (p = 0.41), but the duration of stent patency in tandem ureteral stenting was significantly longer (p = 0.022). The mean patency time was 176.7 ± 21.3 days for single ureteral stenting, and 214.7 ± 21.0 days for tandem ureteral stenting. The complications of ureteral stenting were urinary tract infection (n = 18), lower urinary tract symptoms (n = 5), haematuria (n = 3), and stent migration (n = 1).

CONCLUSIONS

Tandem ureteral stenting is a safe and feasible treatment for MUO, and had better efficacy compared to single ureteral stenting.

KEY POINTS

• Ureteral stenting is an established treatment for the management of malignant ureteral obstruction (MUO) • Prospective single-centre study showed that tandem ureteral stenting is a safe and feasible treatment for MUO • Tandem ureteral stenting provides longer stent patency compared to single ureteral stenting in patient with MUO.

Tandem ureteral stents in the management of double-J stent dysfunction in gynecological malignancies

PURPOSE

The goal of this study was to determine the efficacy and safety of tandem ureteral stent placement in the management of malignant ureteral obstruction (MUO) refractory to single ureteral double-J stent drainage in women with gynecological malignancies.

MATERIALS AND METHODS

A retrospective study was performed on 14 women (mean age, 54.5±9.6 [SD] years; range: 38-70 years) who had tandem stent placement following failed single ureteral double-J stent placement from 2012 to 2017. Survival analyses were performed with Kaplan-Meier method.

RESULTS

Twenty-nine successful procedures were performed on 19 ureters (19 primary stent placement and 9 exchange procedures). Technical success of primary tandem stent placement was 95% (19/20 procedures). Mean follow-up was 180.1±173.7 (SD) days (range: 62-616 days). Median estimated survival of the patients was 118 days (Q1: 261, Q3: 95; range: 62-616 days). Primary stent failure rate was 25% and assisted stent failure rate was 21.4%. There was no significant difference among survival of patients with and without tandem stent failure. Mean estimated primary stent patency and assisted stent patency were 171.4±13.8 (SD) days and 409.9±59.8 (SD) days, respectively. Four patients underwent 1 to 3 stent exchanges. Median exchange time was 181 days (Q1: 151, Q3: 191, range: 141-214 days) and technical success rate was 100%. Grade 2 and 3 complication rates were 25% and 3.6%, respectively.

CONCLUSION

Tandem ureteral stent placement is a feasible, safe and effective procedure for the management of failed ureteral double-J stent placement in women with gynecological malignancies.

The resonance® metallic ureteric stent in the treatment of chronic ureteric obstruction: a safety and efficacy analysis from a contemporary clinical series

BACKGROUND

We evaluate the efficacy and safety of metallic ureteric stenting using the Cook Resonance® stent in the treatment of chronic ureteric obstruction of benign and malignant aetiology. Published experience of using this stent in this context is limited. We add to the body of literature on this topic.

METHODS

All patients who had a Resonance® metallic stent inserted between April 2009 and November 2014 in our institution were identified from a prospectively maintained stent-database. Primary outcome was relief of ureteric obstruction, defined by successful clinical and radiological treatment of hydronephrosis/hydroureter. Secondary outcome measures included operative time, radiological exposure, total stent dwell time (defined as the cumulative time in months for which a Resonance® metallic stent was in situ), and early and late complications.

RESULTS

Twenty-one patients underwent 52 stent insertion episodes (SIE). Median age was 58 years (range 39-90). Stent insertion resulted in successful treatment of hydronephrosis/hydroureter in 96% (2 SIE resulted in failure to relieve ureteric obstruction). Median operative time was 21 min (range 12-90) Median radiation exposure was 815.3 cGy/cm2 (range 192.9-5366.3). Median stent dwell time was 19.5 months (range 6-52) in non-malignant and 12 months (range 2-48) in malignant ureteric obstruction. One stent migrated proximally during insertion and had to be retrieved using an antegrade approach. 5 patients re-admitted with haematuria: all resolved without intervention or blood transfusion. 3 episodes of post-operative urinary infection were recorded; all were successfully treated with oral antibiotics.

CONCLUSION

Metallic ureteric stenting using the Resonance® stent is safe and effective for treating ureteric obstruction from both malignant and benign causes. The success rate in our series is 96%.

[Management of ureteral obstruction : Value of percutaneous nephrostomy and ureteral stents]

Ureteral obstruction represents a heterogeneous disease pattern and is treated by ureteral stenting or percutaneous nephrostomy (PCN) depending on the necessity. The benefits of urinary diversion with ureteral stenting or PCN in malignant ureteral obstruction (MUO) for patient survival are only moderate. No differences have been found between ureteral stenting and PCN in MUO with regard to median patient survival and complication rates. In cases of MUO there is currently no evidence that urinary diversion improves the quality of life. Alternative concepts of ureteral stenting, such as tandem ureteral stents, metallic ureteral stents or metal mesh ureteral stents have not yet shown clear benefits. In benign ureteral obstruction, prospective randomized studies have demonstrated comparable quality of life after PCN or ureteral stenting. The method of choice for urinary diversion is influenced by the recommendations, personal experience of the clinician and the availability of the method.

Early Application of Permanent Metallic Mesh Stent in Substitution for Temporary Polymeric Ureteral Stent Reduces Unnecessary Ureteral Procedures in Patients With Malignant Ureteral Obstruction

OBJECTIVE

To identify risk factors for metal stent failure in patients who received polymeric double J (PDJ) ureteral stents for malignant ureteral obstructions (MUOs) and review our clinical experiences using a ureteral metallic stent.

PATIENTS AND METHODS

Patients who underwent metallic stent placement to replace a double J ureteral stent for nonurological MUO between January 2011 and February 2014 were included. The collected data included gender, age, laterality, cause of obstruction, PDJ ureteral stenting duration, immediate success of the metal stent, and additional procedures to relieve obstruction after metal stenting (eg, additional metal stenting or percutaneous nephrostomy (PCN) indwelling catheter placement). Cox regression tests were used for the statistical analyses.

RESULTS

In this analysis 40 ureteral units were included. There was no initial technical failure. However, 9 (22.5%) units required additional procedures due to de novo ureteral obstruction, including additional indwelling metal stents (7.5%), additional PDJ stenting (10%), or indwelling percutaneous nephrostomy (5%). Univariate and multivariate analyses revealed that the duration of previous PDJ ureteral stenting was an independent prognostic factor for predicting ureteral metal stent failure (hazard ratio = 1.063, 95% confidence interval = 1.004-1.125; P = .037).

CONCLUSION

Long-term indwelling of a PDJ ureteral stent increases the risk of additional management for de novo ureteral stricture after ureteral metal stent replacement for nonurological MUO. Our data suggest that careful patient selection and counseling for those at high risk are needed when metal stent replacement is considered for patients with long-term PDJ ureteral stents for MUO.

Stenting for malignant ureteral obstruction: Tandem, metal or metal-mesh stents

Extrinsic malignant compression of the ureter is not uncommon, often refractory to decompression with conventional polymeric ureteral stents, and frequently associated with limited survival. Alternative options for decompression include tandem ureteral stents, metallic stents and metal-mesh stents, though the preferred method remains controversial. We reviewed and updated our outcomes with tandem ureteral stents for malignant ureteral obstruction, and carried out a PubMed search using the terms "malignant ureteral obstruction," "tandem ureteral stents," "ipsilateral ureteral stents," "metal ureteral stent," "resonance stent," "silhouette stent" and "metal mesh stent." A comprehensive review of the literature and summary of outcomes is provided. The majority of studies encountered were retrospective with small sample sizes. The evidence is most robust for metal stents, whereas only limited data exists for tandem or metal-mesh stents. Metal and metal-mesh stents are considerably more expensive than tandem stenting, but the potential for less frequent stent exchanges makes them possibly cost-effective over time. Urinary tract infections have been associated with all stent types. A wide range of failure rates has been published for all types of stents, limiting direct comparison. Metal and metal-mesh stents show a high incidence of stent colic, migration and encrustation, whereas tandem stents appear to produce symptoms equivalent to single stents. Comparison is difficult given the limited evidence and heterogeneity of patients with malignant ureteral obstruction. It is clear that prospective, randomized studies are necessary to effectively scrutinize conventional, tandem, metallic ureteral and metal-mesh stents for their use in malignant ureteral obstruction.

Use of full-length metallic stents in malignant ureteral obstruction

INTRODUCTION

Malignant ureteral obstruction (MUO) has traditionally been a difficult problem to manage. Indwelling ureteral stents have a failure rate up to 50%, necessitating the placement of percutaneous nephrostomy (PCN) drainage, which has associated complications and impacts on quality of life. Recently, metallic ureteral stents have emerged as a treatment for extrinsic ureteral obstruction. We present our initial experience using Resonance (Cook Urologic, Spencer, IN) full-length metallic stents for MUO.

MATERIALS AND METHODS

20 patients (27 renal units) with advanced cancers and MUO were treated with metallic stents. Patients were followed prospectively to evaluate for recurrent obstruction. Perioperative morbidity and overall mortality were recorded.

RESULTS

The mean patient age was 49.9 years (SD 18.9). The primary malignancies causing MUO were gastrointestinal (8), gynecologic (6), genitourinary (2), or other (4). All but two renal units had been previously treated with traditional stents. Eight out of 20 (40%) patients required further intervention for their MUO. Mean time to failure for the metallic stents was 7.4 months (222 days). Two patients required conversion to percutaneous drainage. Five patients required change to traditional stents (3) or removal of metallic stents. At the last follow-up, sixteen patients had died. Fourteen of the sixteen patients died with functioning metallic stents in place, although one patient who initially had bilateral metallic stent placements had a left stent removed due to migration. Of the remaining four living patients, two have functioning metallic stents at a mean follow-up of 42 months.

DISCUSSION

MUO remains a difficult clinical problem in a group of patients with a high mortality. While metallic stents ultimately have a failure rate similar to that of traditional stents, the mean time to failure is longer. Therefore, metallic stents may benefit patients with MUO, because the longer dwell time may eliminate the need for more frequent stent changes or further interventions.

Percutaneous nephrostomy versus indwelling ureteral stent in the management of gynecological malignancies

OBJECTIVES

The aims of this study were to evaluate the efficacy of retrograde ureteral stenting and to identify the predictive factors for potential failure of this technique in women with advanced gynecologic malignancies.

METHODS

From 2006 to 2010, a retrospective analysis was performed on a total of 75 patients with ureteral obstruction due to gynecologic malignancies. This population was divided into group 1 (n = 50) in which retrograde stent placement was successful, and group 2 (n = 25) in which stent placement failed and subsequent percutaneous nephrostomy tube placement was required. Multivariate analysis was done to identify predictors of the failure of ureteral stent insertion.

RESULTS

Multivariate analysis revealed that mean preprocedureal serum cystanin C greater than 2.5 mg/L and length of the ureteral obstruction greater than 3 cm were significant predictors of stent failure. Neither the causes nor location of obstruction predicted the need for percutaneous nephrostomy (PCN). No statistical significance was detected among the subgroups of patients with different degrees of hydronephrosis. Statistical significant differences were found between the 2 groups in procedural time, average cost, and mean interval of stent/catheter replacement. However, no statistically significant difference was found in the median survival time and overall stent-related or catheter-related complications between the 2 groups.

CONCLUSIONS

Retrograde ureteral stenting is a first-line option for managing ureteral obstruction caused by gynecologic malignancies. However, in cases where the preprocedureal mean serum cystanin C is greater than 2.5 mg/L and the length of the ureteral obstruction segment is greater than 3 cm, these patients may be better served by percutaneous drainage.

Stent failure in the management of malignant extrinsic ureteral obstruction: risk factors

There is still controversy surrounding the indications for performing either a retrograde ureteral stent or percutaneous nephrostomy to manage malignant extrinsic ureteral obstruction (MEUO). We retrospectively analyzed 53 patients who underwent a decompression of MEUO using retrograde ureteral stent. Ureteral stent failure occurred in 18 of 53 patients (34%). Multivariate analysis showed that gastrointestinal cancer as the primary disease, poor preoperative performance status and severe preoperative hydronephrosis were independent predictors of stent failure. Based on the present data, we propose an algorithm for the management of MEUO.

Updates on the use of ureteral stents: focus on the Resonance(®) stent

The Resonance(®) metallic ureteral stent is one of the latest additions to the urologist's armamentarium in managing ureteral obstruction. One advantage of this stent over traditional polymer-based stents is resistance to encrustation with stone material, which allows longer dwell times and less frequent exchange procedures. Although exchanging a metallic stent is slightly more complicated than exchanging a polymer stent, the fluoroscopic techniques required are familiar to most urologists. The Resonance stent is also more resistant to compression by external forces, potentially allowing greater applicability in patients with metastatic cancer. Furthermore, the use of this stent in patients with benign ureteral obstruction is shown to be associated with significant cost reduction. Clinical studies on the use of this stent are accumulating and the results are mixed, although Level 1 evidence is lacking. In this article we present a comprehensive review of the available literature on the Resonance metallic ureteral stent.

ACE2 and angiotensin 1-7 are increased in a human model of cardiovascular hyporeactivity: pathophysiological implications

BACKGROUND

ACE and ACE2 produce angiotensin II (Ang II), a vasopressor that induces cardiovascular remodeling, and Ang 1-7, a vasodilator with an antiremodeling effect. While Ang 1-7 has antiarrhythmic properties, at higher concentration it may induce ventricular tachycardia and sudden death. ACE2, therefore, may play an essential role in blood pressure homeostasis, in the long-term complications of hypertension (cardiovascular remodeling), and in the induction of cardiac electric abnormalities. This study evaluated the levels of ACE2 and Ang 1-7 in Bartter's/Gitelman's patients (BS/GS) who have elevated Ang II and endogenous blockade of Ang II type 1 receptor signaling compared with healthy subjects (C) and essential hypertensives (EH). BS/ GS patients were also considered because of their predisposition to cardiac arrhythmias, which has yet to be completely clarified.

METHODS

Mononuclear cell ACE2 and Ang 1-7 were evaluated using western blot.

RESULTS

One-way ANOVA showed that ACE2 and Ang 1-7 levels were significantly different between the three groups (p=0.0074 and p=0.0001, respectively). Post-hoc analysis (Tukey's HSD) showed that both ACE2 (1.59+/-0.63) and Ang1-7 (2.26+/-1.18) were significantly elevated in BS/GS compared with either C (0.98+/-0.45; p=0.008; 1.12+/-0.48, p=0.002, respectively) or EH (1.06+/-0.24; p=0.043; 0.72+/-0.28; p=0.0001, respectively). ACE2 and Ang 1-7 directly correlated only in BS/GS (r=0.91, p<0.0003).

CONCLUSIONS

The elevated ACE2 and Ang 1-7 in BS/ GS patients mirror those in hypertensives and are in line with the clinical, hemodynamic and pathophysiological characteristics of BS/GS, likely contributing to them. In consideration of the clinical picture of these syndromes, the opposite of hypertension, the results of this study further strengthen the importance of the ACE2/Ang 1-7 system in the regulation of vascular tone and cardiovascular biology.

[Duplex ureteral stenting for intrinsic and extrinsic ureteral strictures: an effective and elegant alternative]

BACKGROUND

Duplex or twin ureteral stenting has previously been described as a viable option for patients where single double-J ureteral stenting has failed in order to avoid nephrostomies or further surgical intervention. We assessed a series of 20 patients at our institution after unsuccessful primary single ureteral stenting where parallel ureteral stents were inserted.

METHODS

Between 2003 and 2009, 20 patients underwent double-J ureteral stenting for ureteral compression or ureteral strictures. After failure of single stenting two ureteral stents were consecutively inserted into the ureter in a parallel fashion after dilating the ureter up to 14 F. The second stent was passed over a hydrophilic guidewire while holding the first stent secure to prevent dislocation.

RESULTS

In all patients the insertion of two parallel stents was technically possible. In 8 of 12 patients with extrinsic tumor compression the stents provided sufficient drainage (67%). When the stricture was due to surgery or radiation two of three patients were successfully diverted with twin stents. In five patients with a ureteral stricture due to malignant disease the stenting did not provide sufficient drainage and a nephrostomy had to be placed after a mean duration of 19 days. Two of those patients were later managed with a pyelovesical bypass. Three patients were later managed with a ureterocystoneostomy (psoas hitch). In four of five patients with benign disease a long-term management was feasible. The patient with retroperitoneal fibrosis developed immediate hydronephrosis and severe flank pain and ultimately underwent an ileal ureter replacement. In three patients with a benign ureteral stenosis after stone therapy, hysterectomy, or colon ureter replacement, a temporary duplex stenting sufficiently resolved the hydronephrosis for spontaneous urine passage. In one patient the duplex stenting prevented a kidney stone from dislocating into the ureter during lithotripsy.

CONCLUSIONS

Duplex or twin (double) ureteral stenting is a valid option in selected patients to avoid the placement of a nephrostomy. Severe stenosis may however demand a nephrostomy insertion or more invasive procedures in the later course. For certain benign ureteral strictures a therapeutic dilating effect of the two ureteral stents that makes further intervention unnecessary can be discussed.

Endourologic management of malignant ureteral obstruction: indications, results, and quality-of-life issues

Obstruction of the upper urinary tract is a problem commonly faced by practicing urologists. The constant evolution in endourology has effectively facilitated minimally invasive management of upper-tract obstruction. In a case in which malignancy is the cause of obstruction, however, the situation significantly changes. Questions arise regarding the need for relieving the obstruction, the means to accomplish this, and the benefits and drawbacks of each technique regarding both their efficacy and their impact on the patients well-being and the crucial issue of quality of life in the face of malignancy.

Analysis of ureteral stent compression force and its role in malignant obstruction

PURPOSE

Extrinsic ureteral obstruction can be a challenging entity for the urologist since half of the ureteral stents placed for malignant obstruction fail. We evaluated the resistance to radial compression of various stents.

MATERIALS AND METHODS

Silhouette(R) 4.6Fr, 6Fr and 8Fr, Sof-Curl Tecoflex 6Fr, Resonance 6Fr, Polaris Ultra 6Fr and 7Fr, and Percuflex 6Fr and 8Fr stents were tested. The force needed to compress the stent to 50% of its original external diameter was measured at 3 locations along the stent length, including proximal, middle and distal. Statistical analysis was performed.

RESULTS

Statistically greater force was required to compress the Resonance and Silhouette stents compared to all others tested. These results were maintained at all 3 locations along the stent. Only the Polaris 6Fr stent differed in resistance to compression along the stent length.

CONCLUSIONS

The significantly higher forces required to compress the Resonance and Silhouette stents may translate into improved success in patients with malignant ureteral obstruction.

Percutaneous Nephrostomy and Ureteric Stent Insertion for Acute Renal Deobstruction Consensus Based Guidance

Objective:

Ureteric obstruction can be relieved by either percutaneous nephrostomy (PCN) or retrograde ureteric stenting (RUS). Both are associated with variable technical success, complication rates, availability and quality of life issues. Our aim was to generate guidelines for PCN, RUS and the general approach of renal deobstruction in the UK.

Materials and Methods:

Subsequent to a pilot study, a formal postal questionnaire regarding the indication and method of renal deobstruction was sent via the BAUS audit office to members of BAUS, BSIR, BSUR. Data from 227 radiologists and urologists were categorised into areas of “clear agreement” (>75% agreement), “broad agreement” (50–75% agreement) and “no broad consensus” (less than 50% agreement) for any particular method of management.

Results:

In septic patients with renal obstruction, there was “clear agreement” for urgent deobstruction by PCN. If uncorrectable coagulopathy exists then RUS was the preferred option. There was “clear agreement” that patients with acute or chronic renal failure should be deobstructed during working hours if not septic, with “broad agreement” that this should be performed with PCN. Patients with obstruction subsequent to pelvic malignancy and the pregnant patient are discussed.

Conclusion:

The authors hope that these results and recommendations will aid clinical decision-making and aid the development of local and regional PCN and RUS services.

Serum creatinine predicts success in retrograde ureteral stent placement in patients with pelvic malignancies

OBJECTIVES

To evaluate serum hemoglobin, baseline serum creatinine, serum creatinine at the diagnosis of obstructive hydronephrosis, and the increase in serum creatinine greater than baseline to predict for success in retrograde ureteral stent placement in patients with pelvic malignancies.

METHODS

In a retrospective chart review, we identified 57 patients at our institution with obstructive hydronephrosis secondary to pelvic malignancies in which retrograde ureteral stent placement was attempted from January 2002 to May 2005. The patient charts were reviewed for the baseline serum creatinine, preoperative serum creatinine and hemoglobin, and serum creatinine at presentation of obstructive hydronephrosis. This population was divided into group 1 (n = 31, 54%), in which retrograde stent placement was successful, and group 2 (n = 26, 46%), in which stent placement failed and subsequent percutaneous nephrostomy tube placement was required. The Student t test was used to determine whether a significant difference existed between the two groups for each laboratory parameter.

RESULTS

The serum hemoglobin and baseline creatinine were not significantly different between the two groups and could not be used to predict for the success or failure of stent placement (P = 0.10 and P = 0.59, respectively). However, the average serum creatinine at presentation of obstructive hydronephrosis was significantly different between group 1 (2.4 +/- 1.4 ng/dL) and group 2 (5.3 +/- 6.3; P = 0.014), as was an increase in serum creatinine greater than baseline (P = 0.002).

CONCLUSIONS

The results of this study have shown that the serum creatinine level at the presentation of obstructive hydronephrosis can be used to predict for success in retrograde ureteral stent placement in patients with pelvic malignancies.

Management of extrinsic malignant ureteral obstruction with urinary diversion

OBJECTIVE

The effectiveness of urinary diversion for patients with renal insufficiency due to extrinsic ureteral obstruction was assessed.

METHODS

Between 1990 and 2003, 30 males and 45 females, ranging 36-90 years of age (average, 62.7) who had secondary ureteral obstruction due to either a retroperitoneal or pelvic invasion of malignant disease, underwent nephrostomy or ureteral stenting using a double-J stent without side holes.

RESULTS

Ureteral stenting was attempted as an initial procedure in 51 of the 75 cases. The remaining 24 cases had a nephrostomy at the first step. Of 51, 37 cases were successfully stented, while internal stenting was unsuccessful in the remaining 14 cases. These 14 cases were treated with nephrostomy at the second step following the unsuccessful internal stenting. Eight cases of the 37 successfully stented cases were eventually changed to a nephrostomy because of catheter trouble. As a result, 29 cases could be managed by internal ureteral stenting up until the end of their life. The follow-up period for the 75 cases who underwent urinary diversion ranged from 5 days to 19 months, averaging 5.7 months. The average period from diversion to death was 5.6 months in the internally stented group and 5.9 months in the nephrostomy group.

CONCLUSION

The high patency rate of the internal ureteral stent in our cases might be due to our use of a stent without shaft vent holes.

Novel dual-lumen ureteral stents provide better ureteral flow than single ureteral stent in ex vivo porcine kidney model of extrinsic ureteral obstruction

OBJECTIVES

In the instance of extrinsic ureteral obstruction, indwelling ureteral stents have a high failure rate. Although technically challenging, simultaneous insertion of two ipsilateral stents can achieve better flow rates with time. A novel dual-lumen stent, composed of two adhered ureteral stents, offers the additional benefit of easier placement than a single guidewire. Using a novel ex vivo porcine model, the flow rates within an extrinsically obstructed renal unit were evaluated using two internal ipsilateral stents and two prototype double-lumen stents.

METHODS

Sixteen renal units were harvested from eight adult Yorkshire female pigs. To quantify flow, the kidneys were infused at a constant pressure, and the corresponding ureteral drainage was measured for a defined interval. The flow was measured with a standard 7F double-pigtail stent, two ipsilateral 7F double-pigtail stents, a 7F novel double-lumen stent designed with both distal lumens open, and a 7F novel double-lumen stent with one distal lumen closed. The intraluminal and extraluminal flow in obstructed and nonobstructed systems was measured.

RESULTS

The two ipsilateral standard stents or prototype double stents achieved better flow down the ureter than did one standard stent (P <0.05). The intraluminal and extraluminal flow in the novel stents was statistically greater than the corresponding flow in the standard double-pigtail stent (P <0.01). The extraluminal and obstructed flow was lowest for the standard double-pigtail stent.

CONCLUSIONS

Novel dual-lumen prototype ureteral stents provided better flow than a single stent in extrinsically obstructed ureters with the proposed added benefit of easier retrograde insertion compared with a single guidewire.

The management of malignant ureteral obstruction treated with ureteral stents

PURPOSE

We developed an algorithm for the management of ureteral obstruction due to malignant extrinsic compression.

MATERIALS AND METHODS

We retrospectively reviewed all ureteral stents placed for noncalculous reasons at our institution from January 1, 1990 to January 1, 2004. Further clinical information was gathered from 157 patients with malignant extrinsic ureteral compression. Failure was defined as recurrent ureteral obstruction or an inability to place stents cystoscopically.

RESULTS

A total of 157 patients underwent retrograde ureteral stent attempt for malignant extrinsic ureteral obstruction. Mean patient age was 54.7 years (range 23 to 83) and average followup was 13.6 months. Of our patients 61% were women, and the most common cancer diagnoses were ovarian cancer (in 26), lymphoma (17) and cervical cancer (16). A total of 24 patients required immediate percutaneous nephrostomy (PCN) referral. There were 32 patients who experienced a late failure and required PCN (average 180 days after initial stent), and 83 patients in our series (52.9%) who experienced 110 major complications. Type of cancer did not predict need for PCN. However, when invasion into the bladder was noted on cystoscopy, 55.9% (19 of 34, p = 0.008) progressed to PCN referral. A total of 77 patients underwent stent replacement on average 2.8 times and with an interval of 95 days.

CONCLUSIONS

In our series patients with malignant extrinsic ureteral compression presenting for ureteral stent(s) experienced a failure rate of 35.7% (56 of 157). Invasion at cystoscopy had a significant predictive value for progression to PCN. We present an algorithm on the management of extrinsic malignant ureteral obstruction.

Using two ipsilateral double j ureteral stents for extrinsic ureteral obstruction due to colon carcinoma

Although double J (DJ) ureteral stents are widely used in extrinsic ureteral obstruction, there are few studies using ipsilateral two DJ stents in the same ureter. We report using ipsilateral two ureteral DJ stents in the same ureter in a patient with extrinsic ureteral obstruction due to colon carcinoma.

The impact of treatment for gynecological cancer on health-related quality of life (HRQoL): a systematic review

Gynecologic cancers are major sources of mortality and morbidity. Although many review articles have reported on the impact of these diseases on health-related quality of life (HRQoL), none have reviewed the evidence in specific relation to the effect of treatment on HRQoL. Consequently, we systematically searched 4 electronic databases and hand-searched relevant reference lists and bibliographies to identify literature on this subject. Only 47 studies used a validated questionnaire to measure HRQoL. Although a meta-analysis was not possible, we found HRQoL rarely included as a treatment outcome, and when included assessment was often methodologically flawed. Seldom were pretreatment and posttreatment data collected or treatment regimes documented. Except for a few studies, analysis of HRQoL was conducted on small samples, excluding the cancer site and stage. Consequently, no definitive conclusions could be drawn and therefore we conclude with recommendations for the future reporting of HRQoL in gynecologic oncology studies.

Stent-Change Therapy in Advanced Malignancies with Ureteral Obstruction

BACKGROUND AND PURPOSE

To determine if patients with advanced malignancies and resultant ureteral obstruction who are managed with chronic ureteral stent changes have adequate preservation of renal function and an acceptable rate of complications.

PATIENTS AND METHODS

A retrospective review was conducted on 28 patients who had a stent to relieve ureteral obstruction caused by cancer.

RESULTS

During the study period, 201 stents were placed, a median of 4 (range 1-34) per patient. The mean time from cancer diagnosis to first stent placement was 34 months (range 1-109 months). The median survival after the first stent insertion was 15.3 months (95% CI 15.1, 15.6). Seven patients had worsening renal function and hydronephrosis despite indwelling stents. In these patients, the median time from the first stent to a rising serum creatinine concentration was 17 months (range 1-66 months). No patient required dialysis. Eighteen patients developed a total of 69 urinary tract infections (mean 2.5). Eight patients had a total of 13 episodes of urosepsis. The median infection-free survival was 11.9 months (range 7.7-16.9 months). The median urosepsis-free survival was 28.5 months (range 9.7-47.1 months). Fourteen patients died from their malignancies during the study.

CONCLUSIONS

Stent-change therapy is an efficacious way to treat patients with advanced malignancies and ureteral obstruction, many of whom have a short life expectancy. All patients maintained adequate renal function to obviate dialysis. Most patients with stents in place will die before their renal function deteriorates. They may also benefit from treatment strategies designed to avoid the occurrence of frequent urinary infections.

Urinary diversion in children with pelvic tumors

PURPOSE

The aim of this study was to investigate children presenting with malignant pelvic tumors obstructing the upper urinary tract.

METHODS

Seventeen children with upper urinary tract obstruction by a malignant tumor were reviewed. A nephrostomy tube or Double J (DJ) stent was inserted into each obstructed urinary system and removed after tumor shrinkage and/or hydronephrosis regression.

RESULTS

There were 9 boys and 8 girls in the study; the mean age and median follow-up were 5.7 years and 2.5 years, respectively. The most common obstructing tumor was rhabdomyosarcoma. Twelve children underwent diversion by nephrostomy tubes and 3 by DJ stents; 2 patients underwent resection of the tumors with ureteroureterostomy. Complications after the insertion of the stents included febrile urinary tract infections (UTI) or pyelonephritis in 4 of the children with DJ stents. In the nephrostomy group, febrile UTI developed in 3 and the tube fell out in 1, and was blocked in another. Of the 17 children, 9 have no evidence of disease, 2 are currently under treatment, and 6 died of cancer.

CONCLUSIONS

The prognosis of children with malignant pelvic tumor obstructing the upper urinary system justifies urgent and optimal upper tract diversion, enabling chemotherapy to be started immediately.

15-year experience with the management of extrinsic ureteral obstruction with indwelling ureteral stents

PURPOSE

We assessed the success of retrograde placement of indwelling ureteral stents in the management of ureteral obstruction due to extrinsic compression.

MATERIALS AND METHODS

Between July 1987 and December 2002 adequate followup was available for 101 patients who underwent primary retrograde ureteral stenting for extrinsic ureteral obstruction. Mean age at presentation was 61.4 years (range 33 to 90). Chart review was performed on all patients for primary diagnosis, symptomatology, degree of hydronephrosis, creatinine levels (baseline, treatment and posttreatment), location of compression, size and number of stents used, progression to percutaneous nephrostomy tube (PNT), stent failure, days to stent failure, post-stent therapy and status at last followup.

RESULTS

Mean length of followup was 11 months (range 1 to 127). In 101 patients 138 ureteral units (UU) were stented. Total stent failure occurred in 41 (40.6%) patients and 58 (42.0%) UU. A total of 40 (29.0%) UU required PNTs at a mean of 40.3 days (range 0 to 330) with 18 PNTs placed in less than 1 week. Cases of stent failure that did not undergo PNT placement included 18 (13.0%) UU at a mean of 52.4 days (range 3 to 128). A total of 90 (89.1%) patients had metastatic cancer at stenting with 32.2% dead at 5.8 months (range 1 to 32). Univariate and multivariate analyses identified cancer diagnosis, baseline creatinine greater than 1.3 mg/dl and post-stent systemic treatment as predictors of stent failure. Proximal location of compression and treatment creatinine greater than 3.11 mg/dl were marginal predictors of failure on univariate analysis, while proximal location of obstruction was also marginally significant on multivariate analysis. No predictors were identified for early stent failure (less than 1 week).

CONCLUSIONS

At almost 1 year followup stent failure due to extrinsic compression occurred in nearly half of treated patients. Analysis of data revealed a diagnosis of cancer, baseline mild renal insufficiency and metastatic disease requiring chemotherapy or radiation as predictors of stent failure. Managing extrinsic compression by retrograde stenting continues to be a practical but guarded decision and should be tailored to each patient.

Palliative surgery of soft tissue sarcoma

Despite an increasing trend towards early diagnosis of breast cancer,patients still present with locally advanced disease. Also, in some patients chemotherapy will fail, and local and regional recurrence will occur. This article outlines options for palliative care for such patients.

Prospective evaluation of ureteral stent durability in patients with chronic ureteral obstruction

OBJECTIVES

To prospectively evaluate the durability of ureteral stents in patients with chronic ureteral obstruction.

METHODS

Twenty-nine renal units from 22 patients with known chronic ureteral obstruction treated with indwelling ureteral stents were studied at 3, 6, 9, and 12 months after initial stent placement (7 to 8F Percuflex) by abdominal x-ray, serum creatinine, and renal and bladder ultrasonography. Renal ultrasound scans were performed by a single senior radiologist with specific attention paid to any increase in hydronephrosis and to the presence of ureteral jets. The stent was changed when calcifications were seen along the stent on abdominal x-ray, if an increase in serum creatinine occurred, or if any increase in hydronephrosis or absence of ureteral jets was seen on ultrasonography. In addition, the stents were changed if new-onset flank pain and/or pyelonephritis developed. If none of the above occurred, the stents were changed after 12 months.

RESULTS

Two patients died of metastatic cancer, leaving 25 renal units available for follow-up. The mean and median time to stent change were 6 months. At 3, 6, 9, and 12 months, the number of renal units that did not meet the criteria warranting stent change was 18 (72%), 12 (48%), 6 (24%), and 2 (8%), respectively. Only 2 (8%) of 25 renal units did not meet any exclusion criteria at 12 months. The most common reasons for requiring the stent to be changed were new-onset flank pain in 8 (35%), an increase in serum creatinine in 7 (30%), and new-onset or increased hydronephrosis in 7 (30%). No criteria were useful in predicting how long stents could be maintained in an individual patient.

CONCLUSIONS

The stents were maintained for more than 6 months in 12 (48%) of 25 renal units. However, very few patients were able to maintain chronic ureteral stents for 12 months without requiring stent change based on our criteria.

Simultaneous multiple double pigtail stents for malignant ureteral obstruction

Ureteral obstruction caused by extrinsic compression from pelvic malignancies often persists after ureteral stent placement. We describe a new technique and present our experience with the simultaneous placement of two ipsilateral ureteral stents after simple stenting has failed.