Intraprostatic Botulinum Toxin Type A Injection in Patients Unfit for Surgery Presenting with Refractory Urinary Retention and Benign Prostatic Enlargement. Effect on Prostate Volume and Micturition Resumption

ObjectivesTo evaluate the effect of intraprostatic injection of botulinum toxin A (BoNTA) on prostate volume and refractory urinary retention in patients with benign prostatic enlargement.MethodsTwenty-one men with benign prostatic enlargement on chronic indwelling catheter for at least 3 mo who were not candidates for surgery because of poor general condition received 200 U BoNTA in the transition zone by transrectal approach under ultrasound guidance. Patients were reevaluated at 1 and 3 mo posttreatment.ResultsPatients had a mean age of 80 ± 2 yr. Injections were done without anaesthetic support as an outpatient procedure. No significant local effects occurred. Baseline prostate volume of 70 ± 10 ml decreased to 57 ± 10 ml (p < 0.0006) at 1 mo and to 47 ± 7 ml (p = 0.03 against 1 mo) at 3 mo. At 1 mo, 16 patients (76%) could resume voiding with a mean Qmax of 9.0 ± 1.2 ml/s. At 3 mo, 17 patients (81%) voided with a mean Qmax of 10.3 ± 1.4 ml/s. Residual urine was 80 ± 19 ml and 92 ± 24 ml at the two time points, respectively. Mean serum total PSA decreased from 6.0 ± 1.1 ng/ml at baseline to 5.0 ± 0.9 ng/ml at 3 mo (p = 0.04).ConclusionsBoNTA injection into the prostate swiftly reduces prostate volume and may be a promising treatment for refractory urinary retention in patients with benign prostatic enlargement who are unfit for surgery. Future studies will determine the duration of BoNTA effect.