Évaluation prospective du traitement de l’incontinence urinaire post-prostatectomie par injections intrasphinctériennes de cellules musculaires autologues

[Functional results and treatment of functional dysfunctions after radical prostatectomy]

OBJECTIVE

To describe the functional results and treatment of functional dysfunctions after radical prostatectomy for localized prostate cancer.

MATERIAL AND METHOD

Bibliography search was performed from the database Medline (National Library of Medicine, Pubmed) selected according to the scientific relevance. The research was focused on continence, potency, les dyserections, couple sexuality, incontinence, treatments of postoperative incontinence, dysrection and trifecta.

RESULTS

Radical prostatectomy is an elaborate and challenging procedure when carcinological risk balances with functional results. Despite recent developments in surgical techniques, post-radical prostatectomy urinary incontinence (pRP-UI) continues to be one of the most devastating complications, which affects 9-16% of patients. Sphincter injury and bladder dysfunction are the most common causes or pRP-UI. The assessment of severity of pRP-UI that affects the choice of treatment is still not well standardized but should include at least a pad test and self-administered questionnaires. The implantation of an artificial urinary sphincter AMS800 remains the gold standard treatment for patients with moderate to severe pRP-UI. The development of less invasive techniques such as the male sling of Pro-ACT balloons has provided alternative therapeutic options for moderate and slight forms of pRP-UI. Most groups now consider the bulbo-urethral compressive sling as the treatment of choice for patients with non-severe pRP-UI. The most appropriate second-line therapeutic strategy is not clearly determined. Recent therapies such as adjustable artificial urinary sphincters and sling and stem cells injections have been investigated. Maintenance of a satisfying sex life is a major concern of a majority of men facing prostate cancer and its treatments. It is essential to assess the couple's sexuality before treating prostate cancer in order to deliver comprehensive information and consider early therapeutic solutions adapted to the couple's expectations. Active pharmacological erectile rehabilitation (intracavernous injections or phosphodiesterase type 5 inhibitors [PDE5i] on demand, during in the month following surgery) or passive (daily PDE5i after surgery) might improve the quality of erections especially in response to PDE5i. Unimpaired aspects of sexual response (orgasm) may, when the erection is not yet recovered, represent an alternative allowing the couple to preserve intimacy and complicity. Androgen blockade is a major barrier to maintain or return to a satisfying sex. Trifecta is a simple tool to present in one way the results of radical prostatectomy: in case of bilateral neurovascular preservation, Trifecta is 60% whatever the surgical approach.

CONCLUSION

Radical prostatectomy is an elaborate and challenging procedure when carcinological risk balances with functional results. Various treatments of postoperative incontinence and dysrections exist. Functional disorders after surgery have to be treated to ameliorate quality of life of patients.

Current interventional management of male stress urinary incontinence following urological procedures

Introduction

Despite improvements in surgical techniques and implementation of minimally invasive procedures, male stress urinary incontinence affects a substantial number of patients after prostatic surgery. In response to increasing demand of optimal treatment modality, new alternatives to artificial urinary sphincter have recently been introduced. This review summarises the therapeutic surgical options with their outcomes in management of postprostatectomy stress incontinence.

Material and methods

We performed a literature review by searching the PubMed, Web of Science and Embase databases for articles published from January 2000 until April 2015 based on clinical relevance.

Results

Artificial urinary sphincter is currently considered the “gold standard” treatment of male stress urinary incontinence. Although the new devices in this group have recently been investigated, the AMS 800 remains the only widely used implant. Male slings and adjustable continence devices, achieve the social continence rates up to 60%. Periurethral injections of bulking agents, have limited efficacy of male stress incontinence. Argus sling and ProACT are both associated with substantial explantation rates. Stem cell therapy is a promising option but still requires additional testing.

Conclusions

The development of new alternatives to artificial urinary sphincter is constantly progressing. Although recently introduced minimally invasive treatment options have not yet surpassed the outcomes of the artificial urinary sphincter they should continue to be evaluated and compared against the gold standard.

Intraurethral injection of autologous minced skeletal muscle: a simple surgical treatment for stress urinary incontinence

PURPOSE

Intraurethral injection of in vitro expanded autologous skeletal muscle derived cells is a new regenerative therapy for stress urinary incontinence. We examined the efficacy and safety of a simpler alternative strategy using freshly harvested, minced autologous skeletal muscle tissue with its inherent content of regenerative cells.

MATERIALS AND METHODS

A total of 20 and 15 women with uncomplicated and complicated stress urinary incontinence, respectively, received intraurethral injections of minced autologous skeletal muscle tissue and were followed for 1 year. Efficacy was assessed by the number of leakages in a 3-day diary and by ICIQ-SF scores. We calculated the rates of cure, defined as zero leaks in 3 days plus an ICIQ-SF score of 5 or less, and improvement, defined as simultaneous decreases in each outcome measure.

RESULTS

Significant reductions were observed in each group in the mean number of leakages (p <0.01) and in ICIQ-SF scores (p <0.001). In the uncomplicated group cure and improvement were observed in 25% and 63% of patients, and in the complicated group they were noted in 7% and 57%, respectively. No voiding dysfunction developed and only minor adverse events were noted.

CONCLUSIONS

Intraurethral injection of minced autologous muscle tissue is a simple surgical procedure that appears safe and moderately effective in women with uncomplicated stress urinary incontinence. It compares well to a more complicated regenerative strategy using in vitro expanded muscle derived cells.

Restoration of anal sphincter function after myoblast cell therapy in incontinent rats

Fecal incontinence (FI) remains a socially isolating condition with profound impact on quality of life for which autologous myoblast cell therapy represents an attractive treatment option. We developed an animal model of FI and investigated the possibility of improving sphincter function by intrasphincteric injection of syngeneic myoblasts. Several types of anal cryoinjuries were evaluated on anesthetized Fischer rats receiving analgesics. The minimal lesion yielding sustainable anal sphincter deficiency was a 90° cryoinjury of the sphincter, repeated after a 24-h interval. Anal sphincter pressure was evaluated longitudinally by anorectal manometry under local electrostimulation. Myoblasts were prepared using a protocol mimicking a clinical-grade process and further transduced with a GFP-encoding lentiviral vector before intrasphincteric injection. Experimental groups were uninjured controls, cryoinjured + PBS, and cryoinjured + myoblasts (different doses or injection site). Myoblast injection was well tolerated. Transferred myoblasts expressing GFP integrated into the sphincter and differentiated in situ into dystrophin-positive mature myofibers. Posttreatment sphincter pressures increased over time. At day 60, pressures in the treated group were significantly higher than those of PBS-injected controls and not significantly different from those of normal rats. Longitudinal follow-up showed stability of the therapeutic effect on sphincter function over a period of 6 months. Intrasphincteric myoblast injections at the lesion borders were equally as effective as intralesion administration, but an injection opposite to the lesion was not. These results provide proof of principle for myoblast cell therapy to treat FI in a rat model. This strategy is currently being evaluated in humans in a randomized double-blind placebo-controlled clinical trial.

Periurethral skeletal myofibre implantation in patients with urinary incontinence and intrinsic sphincter deficiency: a phase I clinical trial

WHAT'S KNOWN ON THE SUBJECT? AND WHAT DOES THE STUDY ADD?: Cell therapy using muscle precursor cell (MPC) injections has shown promise for urinary incontinence due to intrinsic sphincter deficiency (ISD), but the cell-preparation process is complex and costly. Implantation of freshly isolated myofibres carrying MPCs, mainly satellite cells, was very efficient in repairing muscle damage in recent animal experiments. In a phase I clinical trial, we investigated whether periurethral myofibre implantation generated local myogenesis and improved continence in 10 patients (five men and five women) with ISD. We found that myofibre implantation increased intraurethral pressure and periurethral electromyographic activity in patients with ISD. There were no serious side-effects.

OBJECTIVES

To assess the safety of periurethral myofibre implantation in patients with urinary incontinence due to intrinsic sphincter deficiency (ISD) To assess the resulting myogenic process and effects on urinary continence.

PATIENTS AND METHODS

An open-label non-randomised phase I clinical trial was conducted in five men and five women with ISD (mean age, 62.5 years). A free muscle strip from the patient's gracilis muscle was implanted around the urethra as a means to deliver locally myofibres and muscle precursor cells (MPCs). Patients were assessed for collection formation and incomplete bladder emptying. The maximum urethral closure pressure (MUCP) and concomitant periurethral electromyographic (EMG) activity were recorded before surgery and 1 and 3 months after surgery. Continence was assessed using the 24-h pad test and self-completed questionnaires, for 12 months.

RESULTS

There were no serious side-effects. Continence improved significantly during the 12-month follow-up in four of the five women, including two who recovered normal continence. In the women, MUCP increased two-fold and de novo EMG periurethral activity was recorded. In the men, MUCP and EMG recordings showed similar improvements but the effect on continence was moderate. The few patients enrolled could affect these results.

CONCLUSIONS

This is the first report of a one-step procedure for transferring autologous MPCs via myofibre implantation in patients with ISD. EMG and urodynamic assessments showed improvement of periurethral muscle activity. Further work is needed to confirm and improve the therapeutic efficiency of this procedure.

[Cellular therapy and urinary incontinence]

AIM

The objective of the current study was to perform a review of literature concerning stem cells therapy (preclinical and clinical studies) applied to the treatment of stress urinary incontinence (SUI).

METHODS

Review of literature (Pubmed/Medline) using the following key words: stem cells, urinary incontinence, stress. Among 38 published articles (English or French language), 16 studies were selected (comparative preclinical and clinical studies).

RESULTS

Multipotentes mesenchymal stem cells (MSC), present in the adults in most of the tissues derived from the mesoderm have been tested in the treatment of SUI. Three sources of MSC have been mainly used in urology: bone marrow, striated muscle and adipose tissue. The general principle consists in extracting the MSC from the source tissue and grafting these MSC in the injured urinary sphincter. The preclinical studies proved the capacity of these transplanted cells to differenciate into contractile myocytes and to reconstitute nerve junctions. Clinical studies are very different in terms of methodology, with sample size ranging from four to 123 subjects and a median follow-up of 1 year; these studies showed success rates (complete continence) ranging from 12 to 79 % and improvement rates (quality of life and/or pad test) from 13 to 66%. Only one study reported two cases of worsening incontinence after cell therapy.

CONCLUSION

The few available clinical studies have reported that at short-term follow-up, cell therapy was associated with encouraging results with few side effects.