Intraprostatic Botulinum Toxin Type A injection in patients with benign prostatic enlargement: duration of the effect of a single treatment

Abstract

BackgroundBotulinum Toxin Type-A (BoNT/A) intraprostatic injection can induce prostatic involution and improve LUTS and urinary flow in patients with Benign Prostatic Enlargement (BPE). However, the duration of these effects is unknown. The objective of this work was to determine the duration of prostate volume reduction after one single intraprostatic injection of 200U of Botulinum Toxin Type-A.MethodsThis is an extension of a 6 month study in which 21 frail elderly patients with refractory urinary retention and unfit for surgery were submitted to intraprostatic injection of BoNT/A-200U, by ultrasound guided transrectal approach. In spite of frail conditions, eleven patients could be followed during 18 months. Prostate volume, total serum PSA, maximal flow rate (Qmax), residual volume (PVR) and IPSS-QoL scores were determined at 1, 3, 6, 12 and 18 months post-treatment.ResultsMean prostate volume at baseline, 82 ± 16 ml progressively decreased from month one coming to 49 ± 9,5 ml (p = 0,003) at month six. From this moment on, prostate volume slowly recovered, becoming identical to baseline at 18 months (73 ± 16 ml, p = 0.03). Albeit non significant, serum PSA showed a 25% decrease from baseline to month 6. The 11 patients resumed spontaneous voiding at month one. Mean Qmax was 11,3 ± 1,7 ml/sec and remained unchanged during the follow-up period. PVR ranged from 55 ± 17 to 82 ± 20 ml and IPSS score from10 to 12 points.ConclusionIntraprostatic BoNT/A injection is safe and can reduce prostate volume for a period of 18 months. During this time a marked symptomatic improvement can be maintained.

Treating Benign Prostatic Hyperplasia with Botulinum Neurotoxin

“…Although prostate volume initially decreased (during the first 6 months), slowly increased soon after. On the contrary, Qmax, International Prostate Symptoms Score (IPSS), and PVR remained unchanged during the follow-up period of 18 months [66,71,72].…”

“…A symptomatic improvement has been observed in BoNTtreated patients [2,4,65,67,81,82,[85][86][87][88]. BoNT benefit was evident within one month after the treatment, and it continued throughout the follow up period [65,66,71,72]. A decrease of AUA symptoms score and improvement of peak urinary-flow rate have been observed after BoNT injections [89,90].…”

Treatment of lower urinary tract symptoms: Agents for intraprostatic injection

“…BoNT-A injection in smaller prostate glands caused a much lesser reduction in prostate volume, but a 15% reduction was still observed [32,36]. Independent of the extent of prostate volume reduction, improvements in LUTS and flow have been consistently reported [29][30][31][32][44][45][46][47][48][49][50][51][52][53], while a decrease in total serum PSA was observed in some studies [e.g. 30,45,51], but not in others [52].…”

New intraprostatic injectables and prostatic urethral lift for male LUTS

“…However, the studies have shown no consistency in clinical response in terms of outcome parameters such as symptom scores (for example, the American Urological Association Symptom Index [AUASI] and the International Prostate Symptom Score [IPSS]), reduction in prostate volume, postvoid residual urine volume, peak urinary flow rate (Q max ) and PSA (Table 1). [62][63][64][65][66][67][68][69][70][71][72][73][74][75][76][77][78][79] One intriguing finding is the observation that, even without a relevant impact on prostate volume in selected patients, the application of BoNT-A resulted in an increase in peak urinary flow rate and amelioration of LUTS. 65 This observation highlights the various pathophysiological aspects underlying LUTS suggestive of BPH.…”