Long-term complications arising from bowel interposition in the urinary tract

Laparoscopic intracorporeal ileal ureter replacement: multi-institutional data from 102 patients

OBJECTIVE

To present long-term results of our laparoscopic intracorporeal ileal ureter replacement (LIUR) cohort, including more complex cases of laparoscopic ileocalycostomy.

MATERIAL AND METHODS

We collected records of patients undergoing LIUR. Follow-up included a chemical profile and urine cultures. Imaging consisted of renal ultrasonography, excretory urography, cystography, and computer tomographic or magnetic resonance urography.

RESULTS

One hundred and two patients were included. Stricture location was left (46.1%), right (39.2%), or bilateral (14.7%). No open conversion was performed. Seventy-four patients (72.5%) underwent a total ureteral unit removal. The mean operative time was 289.4 (120 - 680) minutes. The estimated blood loss was 185.2 (10-400) mL. Three patients had intraoperative complications, and fifteen had early postoperative complications. The mean postoperative hospital stay was 12.2 (7-35) days. The mean follow-up duration period was 37.7 (12-162) months. Most patients' follow-up was uneventful (88%), and seven patients presented with Grade 2 late complications.

CONCLUSIONS

Intracorporeal laparoscopic ileal ureteral replacement in cases of extensive ureteral lesions offers optimal long-term outcomes and a low complication rate. Ileocalycostomy constitutes a viable option in the small group of patients with long proximal ureteral strictures and intrarenal pelvis.

Multipotent bone marrow cell-seeded polymeric composites drive long-term, definitive urinary bladder tissue regeneration

To date, there are no efficacious translational solutions for end-stage urinary bladder dysfunction. Current surgical strategies, including urinary diversion and bladder augmentation enterocystoplasty (BAE), utilize autologous intestinal segments (e.g. ileum) to increase bladder capacity to protect renal function. Considered the standard of care, BAE is fraught with numerous short- and long-term clinical complications. Previous clinical trials employing tissue engineering approaches for bladder tissue regeneration have also been unable to translate bench-top findings into clinical practice. Major obstacles still persist that need to be overcome in order to advance tissue-engineered products into the clinical arena. These include scaffold/bladder incongruencies, the acquisition and utility of appropriate cells for anatomic and physiologic tissue recapitulation, and the choice of an appropriate animal model for testing. In this study, we demonstrate that the elastomeric, bladder biomechanocompatible poly(1,8-octamethylene-citrate-co-octanol) (PRS; synthetic) scaffold coseeded with autologous bone marrow-derived mesenchymal stem cells and CD34+ hematopoietic stem/progenitor cells support robust long-term, functional bladder tissue regeneration within the context of a clinically relevant baboon bladder augmentation model simulating bladder trauma. Partially cystectomized baboons were independently augmented with either autologous ileum or stem-cell-seeded small-intestinal submucosa (SIS; a commercially available biological scaffold) or PRS grafts. Stem-cell synergism promoted functional trilayer bladder tissue regeneration, including whole-graft neurovascularization, in both cell-seeded grafts. However, PRS-augmented animals demonstrated fewer clinical complications and more advantageous tissue characterization metrics compared to ileum and SIS-augmented animals. Two-year study data demonstrate that PRS/stem-cell-seeded grafts drive bladder tissue regeneration and are a suitable alternative to BAE.

Negatively charged bladder acellular matrix loaded with positively charged adipose-derived mesenchymal stem cell-derived small extracellular vesicles for bladder tissue engineering

Adipose-derived mesenchymal stem cell-derived small extracellular vesicles (Ad-MSC-sEVs/AMEs) combined with scaffold materials are used in tissue-engineered bladders; however, the lack of retention leads to limited distribution of AMEs in the scaffold areas and low bioavailability of AMEs after bladder reconstruction. To improve retention of AMEs, we developed a novel strategy that modifies the surface charge of the bladder acellular matrix (BAM) via oxidative self-polymerization of dopamine-reducing graphene oxide (GO) and AMEs using ε-polylysine-polyethylene-distearyl phosphatidylethanolamine (PPD). We evaluated two BAM surface modification methods and evaluated the biocompatibility of materials and PPD and electrostatic adherence effects between PPD-modified AMEs and rGO-PDA/BAM in vivo and in vitro. Surface modification increased retention of AMEs, enhanced regeneration of bladder structures, and increased electrical conductivity of rGO-PDA/BAM, thereby improving bladder function recovery. RNA-sequencing revealed 543 miRNAs in human AMEs and 514 miRNAs in rat AMEs. A Venn diagram was used to show target genes of miRNA with the highest proportion predicted by the four databases; related biological processes and pathways were predicted by KEGG and GO analyses. We report a strategy for improving bioavailability of AMEs for bladder reconstruction and reveal that enriched miR-21-5p targets PIK3R1 and activates the PI3K/Akt pathway to promote cell proliferation and migration.

Robot-assisted Radical Cystectomy with Orthotopic Neobladder Reconstruction: Techniques and Functional Outcomes in Males

BACKGROUND

Little is known regarding functional outcomes after robot-assisted radical cystectomy (RARC) and intracorporeal neobladder (ICNB) reconstruction.

OBJECTIVE

To report on urinary continence (UC) and erectile function (EF) at 12 mo after RARC and ICNB reconstruction and investigate predictors of these outcomes.

DESIGN, SETTING, AND PARTICIPANTS

We used data from a multi-institutional database of patients who underwent RARC and ICNB reconstruction for bladder cancer.

SURGICAL PROCEDURE

The cystoprostatectomy sensu stricto followed the conventional steps. ICNB reconstruction was performed at the physician's discretion according to the Studer/Wiklund, S pouch, Gaston, vescica ileale Padovana, or Hautmann technique. The techniques are detailed in the video accompanying the article.

MEASUREMENTS

The outcomes measured were UC and EF at 12 mo.

RESULTS AND LIMITATIONS

A total of 732 male patients were identified with a median age at diagnosis of 64 yr (interquartile range 58-70). The ICNB reconstruction technique was Studer/Wiklund in 74%, S pouch in 1.5%, Gaston in 19%, vescica ileale Padovana in 1.5%, and Hautmann in 4% of cases. The 12-mo UC rate was 86% for daytime and 66% for nighttime continence, including patients who reported the use of a safety pad (20% and 32%, respectively). The 12-mo EF rate was 55%, including men who reported potency with the aid of phosphodiesterase type 5 inhibitors (24%). After adjusting for potential confounders, neobladder type was not associated with UC. Unilateral nerve-sparing (odds ratio [OR] 3.85, 95% confidence interval [CI] 1.88-7.85; p < 0.001) and bilateral nerve-sparing (OR 6.25, 95% CI 3.55-11.0; p < 0.001), were positively associated with EF, whereas age (OR 0.93, 95% CI 0.91-0.95; p < 0.001) and an American Society of Anesthesiologists score of 3 (OR 0.46, 95% CI 0.25-0.89; p < 0.02) were inversely associated with EF.

CONCLUSIONS

RARC and ICNB reconstruction are generally associated with good functional outcomes in terms of UC. EF is highly affected by the degree of nerve preservation, age, and comorbidities.

PATIENT SUMMARY

We investigated functional outcomes after robot-assisted removal of the bladder in terms of urinary continence and erectile function. We found that, in general, patients have relatively good functional outcomes at 12 months after surgery.

Quasi-linear viscoelastic behavior of fresh porcine ureter

PURPOSE

To evaluate the viscoelastic properties of the fresh porcine ureter. Prove the QLV theory can sufficiently model the stress relaxation function of porcine ureters, and determine the QLV model constants which may provide insight into the synthesis of ureteral scaffolds with biomimetic viscoelastic properties in tissue engineering.

METHODS

Hysteresis tests were applied to study the differences in dissipated energy ratio for each different strain group. In stress relaxation tests, samples were sub-grouped and quickly ramping up to 5%, 20%, and 30% strain in each group and gradually relaxed to a corresponding level. Bringing together the quasi-linear viscoelasticity (QLV) theory and stress relaxation function to determine the eight constants of the ureteral tissue, and fitting the raw data with the model via MATLAB.

RESULTS

The hysteresis response measurement results revealed that the porcine ureter was a highly dissipative material and there were differences between toe and linear region in stress-stain curve. The stress relaxation results revealed ureters responded with time-dependent decay of stress. The eight constants of the ureteral QLV model were determined for three different strain groups, and we proved that the QLV model can sufficiently adapt the experimental data of the ureter stress relaxation.

CONCLUSION

This study investigated the time-dependent properties of the porcine ureter, and demonstrated the QLV theory could be used to evaluate the viscoelastic properties of the porcine ureteral tissue.

Considerations for the clinical use of stem cells in genitourinary regenerative medicine

The genitourinary tract can be affected by several pathologies which require repair or replacement to recover biological functions. Current therapeutic strategies are challenged by a growing shortage of adequate tissues. Therefore, new options must be considered for the treatment of patients, with the use of stem cells (SCs) being attractive. Two different strategies can be derived from stem cell use: Cell therapy and tissue therapy, mainly through tissue engineering. The recent advances using these approaches are described in this review, with a focus on stromal/mesenchymal cells found in adipose tissue. Indeed, the accessibility, high yield at harvest as well as anti-fibrotic, immunomodulatory and proangiogenic properties make adipose-derived stromal/SCs promising alternatives to the therapies currently offered to patients. Finally, an innovative technique allowing tissue reconstruction without exogenous material, the self-assembly approach, will be presented. Despite advances, more studies are needed to translate such approaches from the bench to clinics in urology. For the 21^st century, cell and tissue therapies based on SCs are certainly the future of genitourinary regenerative medicine.

Therapeutic potential of adipose-derived mesenchymal stem cell exosomes in tissue-engineered bladders

Mesenchymal stem cells (MSCs) are a therapeutic tool for tissue engineering. However, many studies have recently shown that the therapeutic effects of MSCs are mediated by paracrine signaling and their secretory factors rather than their multidirectional differentiation ability. Exosomes isolated from the conditioned medium of MSCs are considered the main intercellular communication medium between MSCs and their target cells. Exosomes have been utilized in a novel cell-free therapy strategy that has attracted much attention. In this study, we evaluated the effects of a new cell-free tissue-engineered bladder (bladder acellular matrix combined with adipose-derived mesenchymal stem cell exosomes (AMEs)) in vivo and in vitro to prove that AMEs promoted tissue regeneration and functional recovery in a rat bladder replacement model.

Reconstruction of Vascular and Urologic Tubular Grafts by Tissue Engineering

Tissue engineering is one of the most promising scientific breakthroughs of the late 20th century. Its objective is to produce in vitro tissues or organs to repair and replace damaged ones using various techniques, biomaterials, and cells. Tissue engineering emerged to substitute the use of native autologous tissues, whose quantities are sometimes insufficient to correct the most severe pathologies. Indeed, the patient’s health status, regulations, or fibrotic scars at the site of the initial biopsy limit their availability, especially to treat recurrence. This new technology relies on the use of biomaterials to create scaffolds on which the patient’s cells can be seeded. This review focuses on the reconstruction, by tissue engineering, of two types of tissue with tubular structures: vascular and urological grafts. The emphasis is on self-assembly methods which allow the production of tissue/organ substitute without the use of exogenous material, with the patient’s cells producing their own scaffold. These continuously improved techniques, which allow rapid graft integration without immune rejection in the treatment of severely burned patients, give hope that similar results will be observed in the vascular and urological fields.

Bilateral ureteral replacement using ileum in bilateral refractory ureteral stricture with renal insufficiency: a case report and review of literature

Although several studies have reported the efficacy and safety of ileal ureter in refractory ureteral strictures, reports on its long-term outcomes are still insufficient. In this case report, we present an excellent long-term outcome over three years without complication of bilateral ureteral replacement with ileum using ‘7’ shaped configuration in a woman after undergoing radical hysterectomy and radiation therapy who had renal insufficiency due to ureteral stricture. This study gave us a useful information about the feasibility and safety of bilateral ileal ureter in patients with ureteral strictures and renal insufficiency.

Experiences of wearing support garments by people living with a urostomy

BACKGROUND

support garments are commonly worn by people with a urostomy but there are no published data about their experiences of doing so.

AIMS

to identify the views of people living with a urostomy on the role of support garments.

METHODS

a cross-sectional survey of the stoma population's experiences of support garments was conducted in 2018. Recruitment was by social media. The free-text responses provided by a sub-sample of 58 people out of 103 respondents with a urostomy, were analysed.

FINDINGS

thematic analysis revealed four themes: physical self-management; psychosocial self-management; lifestyle; and healthcare advice and support. There were mixed feelings about the value of support garments. Many cited a sense of reassurance and confidence and being able to be more sociable and active; others reported discomfort and uncertainty about their value.

CONCLUSION

these findings add new understanding of experiences of support garments and provide novel theoretical insights about life with a urostomy.

The natural history of untreated muscle-invasive bladder cancer

OBJECTIVE

To describe the natural history of untreated muscle-invasive bladder cancer (MIBC) and compare the oncological outcomes of treated and untreated patients.

PATIENTS AND METHODS

We utilised a database encompassing all patients with newly diagnosed bladder cancer in Stockholm, Sweden between 1995 and 1996. The median follow-up for survivors was 14.4 years. Overall, 538 patients were diagnosed with bladder cancer of whom 126 had clinically localised MIBC. Patients were divided into two groups: those who received radical cystectomy or radiation therapy, and those who did not receive any form of treatment. Multivariable Cox or competing-risks regressions were adopted to predict metastasis, overall survival (OS), and cancer-specific mortality (CSM), when appropriate. Analyses were adjusted for age at diagnosis, sex, tumour stage, clinical N stage, and treatment.

RESULTS

In all, 64 (51%) patients did not receive any definitive local treatment. In the untreated group, the median (interquartile range) age at diagnosis was 79 (63-83) vs 69 (63-74) years in the treated group (P < 0.001). Overall, 109 patients died during follow-up. At 6 months after diagnosis, 38% of the untreated patients had developed metastatic disease and 41% had CSM. The 5-year OS rate for untreated and treated patients was 5% (95% confidence interval [CI] 1, 12%) vs 48% (95% CI 36, 60%), respectively. Patients not receiving any treatment had a 5-year cumulative incidence of CSM of 86% (95% CI 75, 94%) vs 48% (95% CI 36, 60%) for treated patients. Untreated patients had a higher risk of progression to metastatic disease (hazard ratio [HR] 2.40, 95% CI 1.28, 4.51; P = 0.006), death from any cause (HR 2.63, 95% CI 1.65, 4.19; P < 0.001) and CSM (subdistribution HR 2.02, 95% CI 1.24, 3.30; P = 0.004).

CONCLUSIONS

Untreated patients with MIBC are at very high risk of near-term CSM. These findings may help balance the risks vs benefits of integrating curative intent therapy particularly in older patients with MIBC.

Treatment Options and Outcomes in Nonmetastatic Muscle Invasive Bladder Cancer

Muscle-invasive bladder cancer (MIBC) represents 25% of newly diagnosed bladder cancer. MIBC is aggressive and requires timely management. The current standard of care is neoadjuvant chemotherapy followed by radical cystectomy, an approach that could result in significant morbidities. Modifications in the chemotherapy regimens, as well as in perioperative care and surgical approach, have resulted in better overall toxicity profile and faster recovery. However, bladder-preservation in carefully selected patients can lead to acceptable oncological outcomes and better quality of life. Optimization of bladder-preservation protocols and proper identification of patients who tolerate and respond to various treatment modalities will significantly impact patient survival in the coming future.