Stem cells show efficacy, durability in treating SUI

Berlin-Urinary incontinence can be effectively treated with ultrasonography-guided injections of autologous myoblasts and fibroblasts, with long-term results up to 4 years after treatment, according to Austrian researchers.

Hannes Strasser, MD, associate professor of urology at the Medical University of Innsbruck, Austria, led a novel study of 123 women and 63 men, 36 to 84 years of age, with stress urinary incontinence. Patients were treated with transurethral ultrasound-guided injections of autologous myoblasts and fibroblasts obtained from skeletal muscle biopsies. The fibroblasts were injected into the urethral submucosa, and the myoblasts into the rhabdosphincter.

Results at 1-year follow-up showed that incontinence was cured in 79.4% of patients, Dr. Strasser reported at the European Association of Urology annual congress here. Mean incontinence score, quality of life score, thickness of the urethra and rhabdosphincter, and the urethral closure pressures were significantly improved postoperatively.

He noted that no significant changes in the 1-year postoperative results were seen 2 years after implantation of the cells. Furthermore, 3 to 4 years after cell implantation, all patients who were continent at the 1-year follow-up remain continent.

The only intra-operative complication was reported in a male patient who had previously undergone radiation therapy and other urologic surgical procedures; otherwise, only minor postoperative side effects were reported. No long-term side effects, such as urge incontinence or pain following this procedure, have been reported.

"We find this novel therapy of urinary incontinence to be minimally invasive, very effective. The long-term effects are very good, and remain stable over several years," Dr. Strasser said.

Who can benefit most?

"We would like to point out that this therapy is not suitable for all patients who suffer from urinary incontinence. We see that there are certain indications, contraindications, and risk factors that must all be taken into consideration before this therapeutic avenue is chosen," he added. "In general, though, those patients who are suitable for this therapeutic approach can greatly benefit from it."

According to Dr. Strasser, the primary indication for this type of therapy is stress incontinence. Contraindications include hypermobility or descent of the urethra and urinary bladder, pregnancy, immunosuppression, previous radiotherapy of pelvic tumors, urethral strictures or scars, and marked reduction of the length of the membranous urethra after radical prostatectomy and active tumor disease requiring chemotherapy and/or radiotherapy.

Peter F.W.M. Rosier, MD, of the University Hospital Nijmegen, the Netherlands, asked what specific kind of male patients were treated with this therapy.

"All of our male patients who were included in this study had undergone prostate surgery. Sixty-two patients had previously undergone a radical prostatectomy, one patient had previously undergone transurethral resection of the prostate, and we also had eight patients who had additionally undergone radiotherapy," Dr. Strasser replied. "The time between the prostatic surgery of our male patients who were included in the study and the initiation of our therapy ranged between 1.5 years and 10 years, so we basically had a colorful spectrum of male patients in our study.

"Initially, we had set preliminary inclusion criteria for the study, but as the study progressed, we introduced far stricter inclusion criteria, especially for male patients," he added. "For instance, now we do not include those male patients with strictures or scars in the urethra. We noticed in our data that patients who had undergone radiation therapy will not respond well to this kind of therapy."

Myung-Soo Choo, MD, of the University of Ulsan, Seoul, Korea, asked what the main merit was of this kind of therapy compared to other therapies for urinary incontinence.

Dr. Strasser responded that this therapy has a totally different mechanism of action.

"Other therapies work by the injection of huge amounts of material that is intended to passively compress the urethra," he explained. "Our therapeutic technique works by effectively regenerating the urethra and the lower urinary tract. It is a completely different therapeutic approach."