Use of a Segmental Thermoexpandable Metal Alloy Stent in the Management of Malignant Ureteric Obstruction: A Single Centre Experience in the UK

Abstract

Introduction: The Memokath 051™ is a semipermanent inert metal alloy ureteric stent which can bridge strictures and, compared to double J stents, causes less bladder irritation and pain, is more resistant to external compression forces and may be more effective in patients with malignant ureteric obstruction. We present our experience with this novel stent in such cases. Methods: All suitable patients referred to us with malignancy-associated ureteric strictures over a 4-year period had ureteric Memokath 051™ stents inserted. Data on aetiology and position of the strictures as well as length of the Memokath stents used and their efficacy and complications were recorded prospectively. Results: 42 ureteric Memokath 051™ stents were inserted in 37 patients (mean age 64 years). 40.5% of strictures were related to gynaecological cancer, 21% to bowel cancer, 14% were post radiation, 14% occurred in prostate cancer patients and 9.5% were found in other cancers. The mean follow-up was 22 months (range 5–60 months). The main complications were stent migrations in 5, urinary tract infections in 3 and blockage of stent due to progressive transitional cell carcinoma of the ureter in 2 cases. Conclusion: Memokath 051™ ureteric stents are safe, effective and durable in the long-term treatment of malignant strictures.

Comparison of Efficacy and Safety Between a Segmental Thermo-expandable Metal Alloy Spiral Stent (Memokath 051) and a Self-Expandable Covered Metallic Stent (UVENTA) in the Management of Ureteral Obstructions

“…The details of the techniques used have been described previously. [6][7][8][9] In brief, after the length and location of the stricture sites were identified by retrograde pyelography, they were marked on the anterior abdominal wall with a metallic probe to maintain accurate stent placement across the stricture site before insertion of the Memokath 051. The stricture site was dilated, the dilator sheath was passed beyond the proximal site of the stricture, and the stent assembly was inserted into the dilator sheath.…”

Complications After Polymeric and Metallic Ureteral Stent Placements Including Three Types of Fistula

“…5 For an MUS, no reports in the literature have yet studied serious complications such as fistula. 3,6 We report our findings for patients referred with serious ureteral stent-related complications that necessitated surgical correction.…”

“…The long-term failure rate of ureteral stents is high in patients with malignancy-related obstruction, 1 which subsequently necessitates the development and introduction of metallic ureteral stents (MUS). There are three types of MUS: Self-expandable metallic mesh wall stents, 2 novel thermoexpandable nickel-titanium alloy metallic stents (Memokath Ô ), 3 and metallic ureteral stents (Resonance Ò ). 4 Ureteroarterial fistula (UAF), a serious complication associated with ureteral stents, has been well documented in the literature.…”

The Role of Palliative Surgery in Castration-Resistant Prostate Cancer

“…Prior to any endourological, percutaneous, or surgical procedure, treatment must be individualized and risk stratification is of paramount importance [28,29,30,31,32]. A profound decision-making analysis is especially important in patients with an asymptomatic dilatation of the upper urinary tract and a well-functioning contralateral kidney.…”

“…Especially in the clinical scenario of minimally invasive procedures such as the placement of DJ stents or PCN tubes, the decision needs to be made carefully since placement of the devices is usually performed easily but stent infection, encrustation, and blockages are common problems that are difficult to manage and which significantly interfere with the patient's quality of life [30]. New compression-resistant metallic stents seem promising for patients with malignant disease who require long-term urinary drainage [28,29]. However, even with metallic and self-expandable ureteric stents, the main complications remain in about 25-30% of patients: stent migrations, urinary tract infections, and blockage of stents.…”