Endourologic management of malignant ureteral strictures

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

BACKGROUND

Malignant ureteral obstruction (MUO) is a sequela of advanced malignant disease that requires renal drainage, with tandem ureteral stents (TUSs) being a viable option. This study aimed to evaluate the TUS failure rate, associated risk factors, and the feasibility of replacing failed TUSs with a new pair of stents.

METHODS

A retrospective analysis of MUO patients treated with TUS insertion from 2014 to 2022 was conducted. TUS failure was defined as urosepsis, recurrent urinary tract infections, acute kidney failure, or new hydronephrosis on imaging. Cox proportional hazard regression analysis identified the independent predictors of TUS failure.

RESULTS

A total of 240 procedures were performed on 186 patients, with TUS drainage failing in 67 patients (36%). The median time to failure was 7 months. Multivariate analysis revealed female gender (OR = 3.46, p = 0.002), pelvic mass (OR = 1.75, p = 0.001), and distal ureteral obstruction (OR = 2.27, p = 0.04) as significant risk factors for TUS failure. Of the failure group, 42 patients (22.6%) underwent TUS replacement for a new pair. Yet, 24 (57.2%) experienced a second failure, with a median time of 4.5 months. The risk factors for TUS second failure included a stricture longer than 30 mm (OR = 11.8, p = 0.04), replacement with TUSs of the same diameter (OR = 43, p = 0.003), and initial TUS failure within 6 months (OR = 19.2, p = 0.006).

CONCLUSIONS

TUS insertion for the treatment of MUO is feasible and has good outcomes with a relatively low failure rate. Primary pelvic mass and distal ureteral obstruction pose higher risks for TUS failure. Replacing failed TUSs with a new pair has a success rate of 42.8%. Consideration should be given to placing larger diameter stents when replacing failed TUS.

A nomogram to predict stricture-free survival in patients with ureteral stricture after balloon dilation

Background

Balloon dilation is a commonly used minimally invasive endourological treatment of ureteral stricture, but the postoperative recurrence rate is relatively high. And factors contributing to recurrence after treatment are poorly understood. Herein, we sought to develop a novel clinical nomogram to predict ureteral stricture-free survival in patients suffering from ureter stricture and performed balloon dilation.

Methods

The nomogram was established based on a retrospective analysis of 321 patients who received endoscopic balloon dilation alone for ureter strictures from January 2016 to January 2020 in Sun Yat-sen Memorial Hospital using the Cox regression model. Perioperative clinical data and disease outcomes were analyzed. The primary endpoint was the onset of ureteral re-stricture after ureter balloon dilation. Discrimination of the nomogram was assessed by the concordance index (C-index) and the calibration curve. The results were internally validated using bootstrap resampling.

Results

Overall, 321 patients with a median follow-up of 590 days were enrolled in the study, among which 97 patients (30.2%) developed recurrence of ureteral stricture during follow-up. Five variables remained significant predictors of ureteral re-stricture after multivariable analyses: stricture nature (P < 0.001), urinary nitrite (P = 0.041), CKD (P = 0.005), stent retention time (P < 0.001), and balloon size (P = 0.029). The calibration craves for the probability of 1-, 3-, and 5-years stricture-free survival (SFS) presented satisfied with the consistency of nomogram prediction and actual observation. The C-index of the model was 0.74 (95% CI 0.70–0.79).

Conclusions

Our study developed the first nomogram to effectively predict stricture-free survival in patients suffering from ureter stricture after balloon dilation. It is helpful to identify the optimal patients with ureter stricture for balloon dilation and improve treatment outcomes. However, further external validation of the nomogram is warranted.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12894-021-00896-3.

Application of metallic ureteral stents in gynecological malignancies: a literature review

Ureteral obstruction caused by extrinsic compression from advanced pelvic malignancies are not unusual in urology, with gynecological origin being the most common. As minimally invasive treatments for malignant ureteral obstruction (MUO), metallic ureteral stents have been promoted to provide long-lasting urinary patency and overcome the inherent limits of traditional double-J stents. In this review, we demonstrated three types of frequently used metal stents, including coiled stents, self-expendable stents and thermo-expendable stents. The Wallstent presented discrepant patency rates ranging from 6% to 100%, along with a high occlusion rate. The Memokath 051 stent showed satisfactory patency rates, often > 90%, but also a specific higher migration rate. The Resonance stent provided overall promising results with published success rates ranging from 20% to 100%, which on the whole remains relatively high. The long-term effectiveness rendered metal stents as viable options for managing MUO.

Minimally invasive management of ureteral strictures: a 5-year retrospective study

Introduction

Ureteric strictures are well-documented complications related to surgery or radiation therapy. Minimally invasive treatment using endoscopic dilatation or laser incision is the standard practice. There are no existing guidelines on which techniques to use in the treatment of different stricture types and a paucity of data regarding long-term results.

Purpose

Our study aimed to retrospectively assess the long-term efficacy of minimally invasive treatment in benign and malignant ureteric strictures.

Materials and methods

Over a 5-year period, 2007–2012, we analyzed the data of 59 consecutive patients undergoing minimally invasive treatment for symptomatic ureteric strictures. We excluded 16 patients from final analysis due to failed access or loss to follow-up. All patients but one were treated with antegrade, retrograde balloon or catheter dilatations. Successful outcome was defined as an asymptomatic, completely catheter free patient, with stable renal function.

Results

43 patients were eligible for retrospective final analysis. The largest proportion of strictures occurred following surgery combined with radiotherapy 8/43 (19%). Preoperative decompression was required in 30/43 (70%). We identified 32/43 (75%) balloon dilatations, 10/43 (23%) catheter dilatations and 1/43 (2%) laser incision. Overall success rate was 31/43 (72%). All 6 recurrences occurred within 36 months, 4 within the first 12 months. 3/6 patients were successfully re-dilated.

Conclusion

Minimally invasive treatment is a worthwhile alternative in strictures due to previous radiation and/or surgical treatment of malignancies. Most recurrences occurred within the first year. However, late recurrences arise; therefore, patients should be subject to long-term follow-up. Moreover, re-dilatation may be required.

Endoscopic Management of Ureteral Strictures: an Update

PURPOSE OF REVIEW

This review focuses on the role of endoscopic treatment of ureteral stricture disease (USD) in the era of minimally invasive surgery.

RECENT FINDINGS

There is a relative paucity of recent literature regarding the endoscopic treatment of USD. Laser endopyelotomy and balloon dilation are associated with good outcomes in treatment-naïve patients with short (< 2 cm), non-ischemic, benign ureteral strictures with a functional renal unit. If stricture recurs, repetitive dilation and laser endopyleotomy is not recommended, as success rates are low in this scenario. Patients with low-complexity ureteroenteric strictures and transplant strictures may benefit from endoscopic treatment options, although formal reconstruction offers higher rates of success. Formal ureteral reconstruction remains the gold-standard treatment for ureteral stricture disease as it is associated with higher rates of complete resolution. However, in carefully selected patients, endoscopic treatment modalities provide a low-cost, low-morbidity alternative.

The use of internal stents in chronic ureteral obstruction

PURPOSE

Despite the lack of a well delineated definition, chronic ureteral obstruction imposes significant quality of life loss, increased pathological morbidity and risk of mortality as well as substantial economic burden. Ureteral stenting serves as an important therapeutic option to alleviate obstruction. Thus, we assessed the recently published literature on chronic ureteral obstruction; treatment options; types, benefits and shortcomings of current ureteral stents; as well as outcomes and complications of chronic ureteral stenting, with the goal of providing concise management guidelines.

MATERIALS AND METHODS

A systemic literature review was performed on Embase™, PubMed®, Cochrane Controlled Trials Register and Google Scholar™ on ureteral obstruction and internal ureteral stents. Relevant reviews, original research articles and their cited references were examined, and a synopsis of original data was generated on a clinically oriented basis.

RESULTS

Chronic ureteral obstruction can be classified into compression that is either intrinsic or extrinsic to the ureteral wall, or obstruction that is of a benign or malignant origin. Patients with malignant ureteral obstruction generally have a poor prognosis and are often difficult to treat. The aim of stenting is to adequately drain the upper urinary tracts while minimizing hospitalization and the negative impact on quality of life. Facing the challenge of chronic ureteral obstruction, novel stents with new compositions, materials, coatings and designs have been developed. Metallic stents are emerging as efficacious and financially viable alternatives. Early stent related complications include iatrogenic injury, stent migration or patient discomfort, while late complications include infection, difficulties with stent exchange, hardware malfunction, infection and stent encrustation.

CONCLUSIONS

Stenting in chronic ureteral obstruction is a complex and challenging problem. Much work is being done in this area and many options are being explored.

Current status of minimally invasive endoscopic management of ureteric strictures

Endourological techniques are used more often nowadays in the treatment of ureteric strictures of various etiologies. Advances in technology have provided new tools to the armamentarium of the endoscopic urological surgeon. Numerous studies exist that investigate the efficiency and safety of each of the therapeutic modalities available. In this review, we attempt to demonstrate the available and contemporary evidence supporting each minimally invasive modality in the management of ureteric strictures.

[Long-term results for subcutaneous Detour® prosthesis for ureteral obstruction: experiences of implantation, aftercare and management of complications]

BACKGROUND

We present the long-term results of implementation of the Detour® prosthesis as an alternative to established methods of surgical, percutaneous or internal urinary diversion.

PATIENTS AND METHODS

Between 2004 and 2012 a total of 40 prostheses were implanted in 31 patients (mean age 65 years) with ureteral strictures of various origins. In the follow-up the patients underwent examinations and completed questionnaires.

RESULTS

The average follow-up was 23 months (range 1-92 months). Sonographic examinations showed no urinary retention in 38 out of 40 implanted systems. The retention values were stable in 19 patients, improved in 7 and worse in 3. The quality of life (QoL) was high (EORTC QLQ-C30 90%). Intraoperative complications were 2 intestinal lesions and 3 bleeding of the renal-pelvic system. Postoperative urinary tract infections and wound complications were encountered. In the long-term course three infected hydronephroses occurred which were treated and cured with antibiotics and temporary nephrostomy and 4 systems were explanted, including 2 exchanges.

CONCLUSIONS

The system may be considered for patients with ureteral strictures with palliative and curative intent. There were no significant disadvantages in comparison with established methods. There were fewer risks in implantation and complications were manageable. The quality of life was significantly improved.

Ureteral Stricture after Laparoscopic Tubal Ligation due to Suturing of the Serosa

Strictures secondary to traumas of the ureter are some of the complications of urogynecologic surgery. We present a 43-year-old female who had a history of laparoscopic tubal ligation a year ago and was admitted to our department with recurrent flank and inguinal pain. It was soon understood that a suture has pulled the ureter from the lateral serosa of the upper part to the lateral serosa of the lower part causing dilatation of the proximal and midureter because of the previous surgery while there was no damage on the ureteral lumen. Consequently successful reconstruction was performed with open ureteroureterostomy.

Metal ureteral stent for benign and malignant ureteral obstruction

PURPOSE

Metal ureteral stents are a relatively new version of a device with a long history of relieving ureteral obstruction. Metal stents are effective for relieving ureteral obstruction but success regarding patient tolerability has been variable. We present our single institution experience with long-term metal ureteral stent placement.

MATERIALS AND METHODS

The charts of patients undergoing metal ureteral stent placement for chronic ureteral obstruction were reviewed. Data collected included patient age, gender, diagnosis/cause of obstruction, laterality, duration of indwelling metal stent, number of routine metal stent changes, complications and early discontinuations or stent changes.

RESULTS

A total of 23 patients underwent placement of metal ureteral stents between February 2008 and September 2010. Bilateral stents were placed in 5 patients and 9 underwent a yearly metal stent exchange for a total of 42 ureteral units treated with metal ureteral stents. All metal stents were placed to relieve ureteral obstruction due to ureteral stricture, ureteropelvic junction obstruction, retroperitoneal fibrosis or extrinsic malignant obstruction. There were 3 metal stent failures in 2 patients with malignant ureteral obstruction. There were no complications, or early discontinuations or changes due to adverse symptoms, patient dissatisfaction, worsening renal function or progressive hydronephrosis.

CONCLUSIONS

Metal ureteral stents are effective for benign and malignant ureteral obstruction in the absence of urolithiasis. Good tolerability and annual stent exchange make metal stents an appealing alternative for patients with chronic ureteral obstruction treated with indwelling ureteral stents.

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.

Ureteroscopic endoureterotomy

OBJECTIVE

To highlight the current status of ureteroscopic endoureterotomy (UE) by reporting extensive experience with the endoscopic management of ureteric strictures, with special emphasis on factors determining success, and by reviewing publications on the minimally invasive management of ureteric strictures.

PATIENTS AND METHODS

The study comprised 50 patients (mean age 53 years, range 18-85, equal sex distribution) with ureteric strictures of varying causes; all had their stricture treated endoscopically. The follow-up was 0.5-9 years; 10 patients with recurrent strictures had two ipsilateral stents placed to try to improve the outcome, and eight patients with completely obliterating strictures were treated by ureteroscopic re-canalization.

RESULTS

The site of stricture had no bearing on the eventual outcome. Patients with uretero-enteric and malignant strictures did not fare so well. The most important predictor of failure was the length of the stricture, with failure in all seven patients with strictures of > 2 cm. In the 10 patients treated with two ipsilateral stents, eight were successful, which was very promising considering that these patients had recalcitrant strictures and placing one stent had previously failed. The overall success rate was 74%.

CONCLUSION

UE has become the procedure of choice for the initial management of ureteric strictures. Simple balloon dilatation is also effective in certain situations. The characteristics of the stricture often govern the eventual outcome. In properly selected cases success rates of approximately 75% can be expected.

Urologic manifestations of nonurologic diseases gastrointestinal disorders

A variety of common, gastrointestinal diseases result in significant genitourinary tract pathology. In general, knowledge of these associated disease processes permit rapid and accurate diagnosis and treatment. The underlying thread is the recognition of one pathophysiological process to explain patterns of a single disease.

Ureteral stents and their use in endourology

Ureteral stents have assisted urologists in the performance of surgery of the urinary tract for many years. They can have both diagnostic and therapeutic value, but are used most frequently as adjuncts to endoscopic or minimally invasive procedures. This review provides an update of the current uses for ureteral stents, technology of biomaterials, complications associated with indwelling ureteral stents and the future of stents in urology.

Percutaneous nephrostomy versus indwelling ureteral stents in patients with bilateral nongenitourinary malignant extrinsic obstruction

We present five cases of bilateral extrinsic ureteral obstruction in advanced nongenitourinary abdominal malignancy. They show the superiority of percutaneous nephrostomy to indwelling ureteral stents in providing diversion. We suggest that percutaneous nephrostomy drainage should be the management of choice in extrinsic obstruction by advanced abdominal malignancies.