CHICAGO — Autologous stem cells injected into the female urethra and urethral sphincter can stop urinary leakage for up to 2 years, according to new research.
The novel, minimally invasive approach, essentially “reconstructs” the lower urinary tract, said Ferdinand Frauscher, M.D., head of uroradiology at Innsbruck (Austria) University Hospital.
“We believe we have developed a long-lasting and effective treatment that is especially promising, because it is generated from the patient's own body,” he said at the annual meeting of the Radiological Society of North America.
Dr. Frauscher's team treated a cohort of 20 women, aged 36–84 years, who had minor to severe stress urinary incontinence. At 1 year post procedure, 18 (90%) remained continent, with 1 patient maintaining continence for a little more than 2 years, he said.
The technique involves obtaining muscle and connective tissue stem cells from a biopsy of the patient's arm and then culturing them for 6 weeks to yield roughly 50 million myoblasts and 50 million fibroblasts.
In a 15- to 20-minute outpatient procedure, the patient is given local or general anesthesia, and the myoblasts are injected directly into the urethral sphincter. The fibroblasts are first mixed with collagen and then injected into the urethral submucosa.
“We used transurethral three-dimensional ultrasound guidance for the procedure,” said Dr. Frauscher. “With real-time ultrasound, we were able to see exactly where [to place] the new cells.”
Many of the patients regained continence within 24 hours of the procedure.
“During the first days after the procedure, there is a bulking effect from the injection of the fibroblasts, which stay in place because they are mixed with collagen. But after that, the myoblast cells reproduce quickly to form new muscle tissue,” said Dr. Frauscher, also of the department of radiology at the Medical University of Innsbruck.
Endoluminal ultrasound showed a doubling of urethral and sphincter muscle thickness within 1 month of the procedure, while contractility of the sphincter muscle also increased, he said.
Of the two patients who did not regain continence, one improved. The other patient, aged 84, experienced no change.
In elderly women, cell reproduction may be less efficient, and it may be necessary to culture as many as 70 million cells, rather than 50 million, for transplant Dr. Frauscher said.