Long-term results of three different minimally invasive therapies for lower urinary tract symptoms due to benign prostatic hyperplasia: comparison at a single institute

Reoperation after surgical treatment for benign prostatic hyperplasia: a systematic review

Context

Surgical treatment is important for male lower urinary tract symptom (LUTS) management, but there are few reviews of the risks of reoperation.

Objective

To systematically evaluate the current evidence regarding the reoperation rates of surgical treatment for LUTS in accordance with current recommendations and guidelines.

Evidence acquisition

Eligible studies published up to July 2023, were searched for in the PubMed® (National Library of Medicine, Bethesda, MD, USA), Embase® (Elsevier, Amsterdam, the Netherlands), and Web of Science™ (Clarivate™, Philadelphia, PA, USA) databases. STATA® (StataCorp LP, College Station, TX, USA) software was used to conduct the meta-analysis. Random-effects models were used to calculate the pooled incidences (PIs) of reoperation and the 95% confidence intervals (CIs).

Evidence synthesis

A total of 119 studies with 130,106 patients were included. The reoperation rate of transurethral resection of the prostate (TURP) at 1, 2, 3, and 5 years was 4.0%, 5.0%, 6.0%, and 7.7%, respectively. The reoperation rate of plasma kinetic loop resection of the prostate (PKRP) at 1, 2, 3, and 5 years was 3.5%, 3.6%, 5.7%, and 6.6%, respectively. The reoperation rate of holmium laser enucleation of the prostate (HoLEP) at 1, 2, 3, and 5 years was 2.4%, 3.3%, 5.4%, and 6.6%, respectively. The reoperation rate of photoselective vaporization of the prostate (PVP) at 1, 2, 3, and 5 years was 3.3%, 4.1%, 6.7%, and 7.1%, respectively. The reoperation rate of surgery with AquaBeam® at 1, 2, 3, and 5 years was 2.6%, 3.1%, 3.0%, and 4.1%, respectively. The reoperation rate of prostatic artery embolization (PAE) at 1, 2, 3, and 5 years was 12.2%, 20.0%, 26.4%, and 23.8%, respectively. The reoperation rate of transurethral microwave thermotherapy (TUMT) at 1, 2, 3, and 5 years was 9.9%, 19.9%, 23.3%, and 31.2%, respectively. The reoperation rate of transurethral incision of the prostate (TUIP) at 5 years was 13.4%. The reoperation rate of open prostatectomy (OP) at 1 and 5 years was 1.3% and 4.4%, respectively. The reoperation rate of thulium laser enucleation of the prostate (ThuLEP) at 1, 2, and 5 years was 3.7%, 7.7%, and 8.4%, respectively.

Conclusion

Our results summarized the reoperation rates of 10 surgical procedures over follow-up durations of 1, 2, 3, and 5 years, which could provide reference for urologists and LUTS patients.

Systematic review registration

https://www.crd.york.ac.uk/PROSPERO, identifier CRD42023445780.

Minimally invasive treatments for lower urinary tract symptoms in men with benign prostatic hyperplasia: a network meta-analysis

BACKGROUND

A variety of minimally invasive treatments are available as an alternative to transurethral resection of the prostate (TURP) for management of lower urinary tract symptoms (LUTS) in men with benign prostatic hyperplasia (BPH). However, it is unclear which treatments provide better results.

OBJECTIVES

Our primary objective was to assess the comparative effectiveness of minimally invasive treatments for lower urinary tract symptoms in men with BPH through a network meta-analysis. Our secondary objective was to obtain an estimate of relative ranking of these minimally invasive treatments, according to their effects.

SEARCH METHODS

We performed a comprehensive search of multiple databases (CENTRAL, MEDLINE, Embase, Scopus, Web of Science and LILACS), trials registries, other sources of grey literature, and conference proceedings, up to 24 February 2021. We had no restrictions on language of publication or publication status.

SELECTION CRITERIA

We included parallel-group randomized controlled trials assessing the effects of the following minimally invasive treatments, compared to TURP or sham treatment, on men with moderate to severe LUTS due to BPH: convective radiofrequency water vapor therapy (CRFWVT); prostatic arterial embolization (PAE); prostatic urethral lift (PUL); temporary implantable nitinol device (TIND); and transurethral microwave thermotherapy (TUMT).

DATA COLLECTION AND ANALYSIS

Two review authors independently screened the literature, extracted data, and assessed risk of bias. We performed statistical analyses using a random-effects model for pair-wise comparisons and a frequentist network meta-analysis for combined estimates. We interpreted them according to Cochrane methods. We planned subgroup analyses by age, prostate volume, and severity of baseline symptoms. We used risk ratios (RRs) with 95% confidence intervals (CIs) to express dichotomous data and mean differences (MDs) with 95% CIs to express continuous data. We used the GRADE approach to rate the certainty of evidence.

MAIN RESULTS

We included 27 trials involving 3017 men, mostly over age 50, with severe LUTS due to BPH. The overall certainty of evidence was low to very low due to concerns regarding bias, imprecision, inconsistency (heterogeneity), and incoherence. Based on the network meta-analysis, results for our main outcomes were as follows. Urologic symptoms (19 studies, 1847 participants): PUL and PAE may result in little to no difference in urologic symptoms scores (MD of International Prostate Symptoms Score [IPSS]) compared to TURP (3 to 12 months; MD range 0 to 35; higher scores indicate worse symptoms; PUL: 1.47, 95% CI -4.00 to 6.93; PAE: 1.55, 95% CI -1.23 to 4.33; low-certainty evidence). CRFWVT, TUMT, and TIND may result in worse urologic symptoms scores compared to TURP at short-term follow-up, but the CIs include little to no difference (CRFWVT: 3.6, 95% CI -4.25 to 11.46; TUMT: 3.98, 95% CI 0.85 to 7.10; TIND: 7.5, 95% CI -0.68 to 15.69; low-certainty evidence). Quality of life (QoL) (13 studies, 1459 participants): All interventions may result in little to no difference in the QoL scores, compared to TURP (3 to 12 months; MD of IPSS-QoL score; MD range 0 to 6; higher scores indicate worse symptoms; PUL: 0.06, 95% CI -1.17 to 1.30; PAE: 0.09, 95% CI -0.57 to 0.75; CRFWVT: 0.37, 95% CI -1.45 to 2.20; TUMT: 0.65, 95% CI -0.48 to 1.78; TIND: 0.87, 95% CI -1.04 to 2.79; low-certainty evidence). Major adverse events (15 studies, 1573 participants): TUMT probably results in a large reduction of major adverse events compared to TURP (RR 0.20, 95% CI 0.09 to 0.43; moderate-certainty evidence). PUL, CRFWVT, TIND and PAE may also result in a large reduction in major adverse events, but CIs include substantial benefits and harms at three months to 36 months; PUL: RR 0.30, 95% CI 0.04 to 2.22; CRFWVT: RR 0.37, 95% CI 0.01 to 18.62; TIND: RR 0.52, 95% CI 0.01 to 24.46; PAE: RR 0.65, 95% CI 0.25 to 1.68; low-certainty evidence). Retreatment (10 studies, 799 participants): We are uncertain about the effects of PAE and PUL on retreatment compared to TURP (12 to 60 months; PUL: RR 2.39, 95% CI 0.51 to 11.1; PAE: RR 4.39, 95% CI 1.25 to 15.44; very low-certainty evidence). TUMT may result in higher retreatment rates (RR 9.71, 95% CI 2.35 to 40.13; low-certainty evidence). Erectile function (six studies, 640 participants): We are very uncertain of the effects of minimally invasive treatments on erectile function (MD of International Index of Erectile Function [IIEF-5]; range 5 to 25; higher scores indicates better function; CRFWVT: 6.49, 95% CI -8.13 to 21.12; TIND: 5.19, 95% CI -9.36 to 19.74; PUL: 3.00, 95% CI -5.45 to 11.44; PAE: -0.03, 95% CI -6.38, 6.32; very low-certainty evidence). Ejaculatory dysfunction (eight studies, 461 participants): We are uncertain of the effects of PUL, PAE and TUMT on ejaculatory dysfunction compared to TURP (3 to 12 months; PUL: RR 0.05, 95 % CI 0.00 to 1.06; PAE: RR 0.35, 95% CI 0.13 to 0.92; TUMT: RR 0.34, 95% CI 0.17 to 0.68; low-certainty evidence). TURP is the reference treatment with the highest likelihood of being the most efficacious for urinary symptoms, QoL and retreatment, but the least favorable in terms of major adverse events, erectile function and ejaculatory function. Among minimally invasive procedures, PUL and PAE have the highest likelihood of being the most efficacious for urinary symptoms and QoL, TUMT for major adverse events, PUL for retreatment, CRFWVT and TIND for erectile function and PUL for ejaculatory function.

AUTHORS' CONCLUSIONS

Minimally invasive treatments may result in similar or worse effects concerning urinary symptoms and QoL compared to TURP at short-term follow-up. They may result in fewer major adverse events, especially in the case of PUL and PAE; resulting in better rankings for symptoms scores. PUL may result in fewer retreatments compared to other interventions, especially TUMT, which had the highest retreatment rates at long-term follow-up. We are very uncertain about the effects of these interventions on erectile function. There was limited long-term data, especially for CRFWVT and TIND. Future high-quality studies with more extended follow-up, comparing different, active treatment modalities, and adequately reporting critical outcomes relevant to patients, including those related to sexual function, could provide more information on the relative effectiveness of these interventions.

Transurethral microwave thermotherapy for the treatment of lower urinary tract symptoms in men with benign prostatic hyperplasia

BACKGROUND

Transurethral resection of the prostate (TURP) has been the gold-standard treatment for alleviating urinary symptoms and improving urinary flow in men with symptomatic benign prostatic hyperplasia (BPH). However, the morbidity of TURP approaches 20%, and less invasive techniques have been developed for treating BPH. Transurethral microwave thermotherapy (TUMT) is an alternative, minimally-invasive treatment that delivers microwave energy to produce coagulation necrosis in prostatic tissue. This is an update of a review last published in 2012.

OBJECTIVES

To assess the effects of transurethral microwave thermotherapy for the treatment of lower urinary tract symptoms in men with benign prostatic hyperplasia.

SEARCH METHODS

We performed a comprehensive search using multiple databases (the Cochrane Library, MEDLINE, Embase, Scopus, Web of Science, and LILACS), trials registries, other sources of grey literature, and conference proceedings published up to 31 May 2021, with no restrictions by language or publication status.

SELECTION CRITERIA

We included parallel-group randomized controlled trials (RCTs) and cluster-RCTs of participants with BPH who underwent TUMT.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed studies for inclusion at each stage and undertook data extraction and risk of bias and GRADE assessments of the certainty of the evidence (CoE). We considered review outcomes measured up to 12 months after randomization as short-term and beyond 12 months as long-term. Our main outcomes included: urologic symptoms scores, quality of life, major adverse events, retreatment, and ejaculatory and erectile function.

MAIN RESULTS

In this update, we identified no new RCTs, but we included data from studies excluded in the previous version of this review. We included 16 trials with 1919 participants, with a median age of 69 and moderate lower urinary tract symptoms. The certainty of the evidence for most comparisons was moderate-to-low, due to an overall high risk of bias across studies and imprecision (few participants and events). TUMT versus TURP Based on data from four studies with 306 participants, when compared to TURP, TUMT probably results in little to no difference in urologic symptom scores measured by the International Prostatic Symptom Score (IPSS) on a scale from 0 to 35, with higher scores indicating worse symptoms at short-term follow-up (mean difference (MD) 1.00, 95% confidence interval (CI) -0.03 to 2.03; moderate certainty). There is likely to be little to no difference in the quality of life (MD -0.10, 95% CI -0.67 to 0.47; 1 study, 136 participants, moderate certainty). TUMT likely results in fewer major adverse events (RR 0.20, 95% CI 0.09 to 0.43; 6 studies, 525 participants, moderate certainty); based on 168 cases per 1000 men in the TURP group, this corresponds to 135 fewer (153 to 96 fewer) per 1000 men in the TUMT group. TUMT, however, probably results in a large increase in the need for retreatment (risk ratio (RR) 7.07, 95% CI 1.94 to 25.82; 5 studies, 337 participants, moderate certainty) (usually by repeated TUMT or TURP); based on zero cases per 1000 men in the TURP group, this corresponds to 90 more (40 to 150 more) per 1000 men in the TUMT group. There may be little to no difference in erectile function between these interventions (RR 0.63, 95% CI 0.24 to 1.63; 5 studies, 337 participants; low certainty). However, TUMT may result in fewer cases of ejaculatory dysfunction compared to TURP (RR 0.36, 95% CI 0.24 to 0.53; 4 studies, 241 participants; low certainty). TUMT versus sham Based on data from four studies with 483 participants we found that, when compared to sham, TUMT probably reduces urologic symptom scores using the IPSS at short-term follow-up (MD -5.40, 95% CI -6.97 to -3.84; moderate certainty). TUMT may cause little to no difference in the quality of life (MD -0.95, 95% CI -1.14 to -0.77; 2 studies, 347 participants; low certainty) as measured by the IPSS quality-of-life question on a scale from 0 to 6, with higher scores indicating a worse quality of life. We are very uncertain about the effects on major adverse events, since most studies reported no events or isolated lesions of the urinary tract. TUMT may also reduce the need for retreatment compared to sham (RR 0.27, 95% CI 0.08 to 0.88; 2 studies, 82 participants, low certainty); based on 194 retreatments per 1000 men in the sham group, this corresponds to 141 fewer (178 to 23 fewer) per 1000 men in the TUMT group. We are very uncertain of the effects on erectile and ejaculatory function (very low certainty), since we found isolated reports of impotence and ejaculatory disorders (anejaculation and hematospermia). There were no data available for the comparisons of TUMT versus convective radiofrequency water vapor therapy, prostatic urethral lift, prostatic arterial embolization or temporary implantable nitinol device.

AUTHORS' CONCLUSIONS

TUMT provides a similar reduction in urinary symptoms compared to the standard treatment (TURP), with fewer major adverse events and fewer cases of ejaculatory dysfunction at short-term follow-up. However, TUMT probably results in a large increase in retreatment rates. Study limitations and imprecision reduced the confidence we can place in these results. Furthermore, most studies were performed over 20 years ago. Given the emergence of newer minimally-invasive treatments, high-quality head-to-head trials with longer follow-up are needed to clarify their relative effectiveness. Patients' values and preferences, their comorbidities and the effects of other available minimally-invasive procedures, among other factors, can guide clinicians when choosing the optimal treatment for this condition.

Efficacy and safety of prostatic artery embolization for benign prostatic hyperplasia: a systematic review and meta-analysis of randomized controlled trials

OBJECTIVE

To investigate the efficacy and safety of prostatic artery embolization (PAE) vs. transurethral resection of the prostate (TURP) in patients affected by benign prostatic hyperplasia (BPH). We also reviewed mean changes from baseline in PAE at selected follow-up points.

METHODS

PubMed, Web of Science, and Embase were searched up to May 1, 2020. Randomized controlled trials on PAE were collected according to specific inclusion and exclusion criteria. Meta-analyses were performed using RevMan 5.3, STATA 14, and GraphPad Prism 8. Pooled patient-reported scores and functional outcomes were calculated by using a fixed or random-effect model.

RESULTS

Eleven articles met our selection criteria and ten independent patient series were included in the final analysis. Pooled estimates suggested no significant difference between TURP and PAE for patient-reported outcomes including International Prostate Symptom Score (2.32 (- 0.44 to 5.09)) and quality of life (0.18 (- 0.41 to 0.77)) at 12 months. PAE was less effective regarding improvements in most functional outcomes such as maximum flow rate, prostate volume, and prostate-specific antigen. Moreover, PAE may be associated with relatively fewer complications, lower cost, and shorter hospitalization. After the PAE procedure, the overall weighted mean differences for all outcomes except sexual health scores were significantly improved from baseline during follow-up to 24 months.

CONCLUSION

PAE is non-inferior to TURP with regard to improving patient-reported outcomes, though most functional parameters undergo more changes after TURP than after PAE. Moreover, PAE can significantly continue to relieve symptoms for 24 months without causing serious complications.

KEY POINTS

• PAE is as effective as TURP in improving subjective symptom scores, with fewer complications and shorter hospitalization times. • PAE is inferior to TURP in the improvement of most functional outcomes. • Improvements due to PAE are durable during follow-up to 24 months.

Cost-effectiveness analysis of six therapies for the treatment of lower urinary tract symptoms due to benign prostatic hyperplasia

OBJECTIVE

To conduct a cost-effectiveness analysis from payers' perspectives of six treatments for lower urinary tract symptoms (LUTS) associated with benign prostatic hyperplasia (BPH) and to examine positioning of these modalities in the marketplace for the best use of health care funds and quality-of-life benefits for patients.

METHODS

The economic analysis was conducted with a Markov model to compare combination prescription drug therapy (ComboRx), minimally invasive therapies (MITs) including convective radiofrequency (RF) water vapor thermal therapy (Rezūm®), conductive RF thermal therapy (Prostiva®), and prostatic urethral lift (UroLift®), and invasive surgical procedures including photovaporization of the prostate (Greenlight® PVP) and transurethral resection of the prostate (TURP). Effects assessed with International Prostate Symptom Score, adverse events, and re-treatment rates were estimated from medical literature; treatments effects were modeled using a common baseline score. Starting with each therapy, patients' transitions to more intensive therapies when symptoms returned were simulated in 6-month cycles over 2 years. Incremental cost-effectiveness ratios (ICERs) were calculated for pairs of treatments; uncertainty in ICERs was estimated with probabilistic sensitivity analyses.

RESULTS

ComboRx was least effective and provided one-third of the symptom relief achieved with MITs. UroLift was similar in effectiveness to Prostiva and Rezūm but costs more than twice as much. The cheaper MITs were ~$900 more expensive than the cost of ComboRx generic drugs over 2 years. TURP and PVP provided slightly greater relief of LUTS than MITs at approximately twice the cost over 2 years; typically, they are reserved for treatment of more severe LUTS.

CONCLUSION

The analysis evaluated the costs and symptom relief of six treatment options in the continuum of care from a common baseline of LUTS severity. Identification of treatments for LUTS/BPH that demonstrate cost-effectiveness and provide appreciable symptom relief is paramount as reimbursement for patient care moves from volume-based services to value-based services.

Disruption of Prostate Microvasculature by Combining Microbubble-Enhanced Ultrasound and Prothrombin

Previous studies have shown a unique method to disrupt tumor vasculature using pulsed, high-pressure amplitude therapeutic ultrasound combined with microbubbles. In this study, we attempted to destroy the prostate vasculature of canine prostates using microbubble-enhanced ultrasound (MEUS) and prothrombin. The prostates of 43 male mongrel canines were surgically exposed. Twenty-two prostates were treated using MEUS (n = 11) or MEUS and prothrombin (PMEUS, n = 11). The other 21 prostates, which were treated using microbubbles (n = 7), ultrasound (n = 7) or prothrombin (n = 7) only, served as the controls. Prothrombin was intravenously infused at 20 IU/kg. MEUS was induced using a therapeutic ultrasound device at a peak negative pressure of 4.47 MPa and a microbubble injection. Contrast-enhanced ultrasound was performed to assess the blood perfusion of the prostates. Then, the prostate tissue was harvested immediately after treatment and at 48 hours later for pathological examination. The contrast-enhanced ultrasound peak value of the prostate decreased significantly from 36.2 ± 5.6 to 27.1 ± 6.3 after treatment in the PMEUS group, but it remained unchanged in the other groups. Histological examination found severe microvascular rupture, hemorrhage and thrombosis in both MEUS- and PMEUS-treated prostates immediately after treatment, while disruption in the PMEUS group was more severe than in the MEUS group. Forty-eight hours after treatment, massive necrosis and infiltration of white blood cells occurred in the PMEUS group. This study demonstrated that PMEUS disrupted the normal microvasculature of canine prostates and induced massive necrosis. PMEUS could potentially become a new noninvasive method used for the treatment of benign prostatic hyperplasia.

Prostatic urethral lift improves urinary symptoms and flow while preserving sexual function for men with benign prostatic hyperplasia: a systematic review and meta-analysis

CONTEXT

Treatment for lower urinary tract symptoms resulting from benign prostatic hyperplasia (BPH) is varied, and significant side effects, particularly concerning sexual function, affect uptake. The prostatic urethral lift (PUL) procedure is a recent addition to the armamentarium for BPH treatment, with independent reports suggesting improvement of symptoms, sexual function, and urinary flow.

OBJECTIVE

We undertook a systematic review and meta-analysis of reported symptomatic, functional, and sexual outcomes following the PUL procedure.

EVIDENCE ACQUISITION

We performed a critical review of Medline, Embase, ScienceDirect, Cochrane Library, and Web of Science databases in May 2014 according to the Preferred Reporting Items for Systematic Review and Meta-Analysis statement. Quality assessment was performed using a modification of the Methodological Index for Non-Randomized Studies tool. All retrospective, prospective, and controlled trials were included for analysis. Symptom scores, sexual health scores, and functional outcomes were pooled and meta-analysed using quality and random-effects models.

EVIDENCE SYNTHESIS

Ten articles comprising six independent patient cohorts were included for analysis. Pooled estimates from between 452 and 680 patients suggested overall improvement following PUL, including symptoms (large gain; standardised mean gain range of 1.3-1.6, International Prostate Symptom Score difference of -7.2 to -8.7 points), maximum flow rate (3.8-4.0 ml/s), and quality of life (2.2-2.4 points). Sexual function was preserved with a small improvement estimated at 12 mo (standardised mean gain range of 0.3-0.4). Pooled estimates were mostly heterogeneous across study groups.

CONCLUSIONS

PUL is a well-tolerated, minimally invasive therapy for BPH that provides favourable symptom, sexual health, and functional outcomes during follow-up to 12 mo. Longer follow-up and larger randomised studies are required to further confirm these preliminary results.

PATIENT SUMMARY

We reviewed the early results of an innovative procedure directed towards the management of prostate enlargement. The results revealed a well-tolerated procedure that produces improvement in urinary symptoms and function while preserving sexual function.

Applicators for magnetic resonance-guided ultrasonic ablation of benign prostatic hyperplasia

OBJECTIVES

The aims of this study were to evaluate in a canine model applicators designed for ablation of human benign prostatic hyperplasia (BPH) in vivo under magnetic resonance imaging (MRI) guidance, including magnetic resonance thermal imaging (MRTI), determine the ability of MRI techniques to visualize ablative changes in prostate, and evaluate the acute and longer term histologic appearances of prostate tissue ablated during these studies.

MATERIALS AND METHODS

An MRI-compatible transurethral device incorporating a tubular transducer array with dual 120° sectors was used to ablate canine prostate tissue in vivo, in zones similar to regions of human BPH (enlarged transition zones). Magnetic resonance thermal imaging was used for monitoring of ablation in a 3-T environment, and postablation MRIs were performed to determine the visibility of ablated regions. Three canine prostates were ablated in acute studies, and 2 animals were rescanned before killing at 31 days postablation. Acute and chronic appearances of ablated prostate tissue were evaluated histologically and were correlated with the MRTI and postablation MRI scans.

RESULTS

It was possible to ablate regions similar in size to enlarged transition zone in human BPH in 6 to 18 minutes. Regions of acute ablation showed a central "heat-fixed" region surrounded by a region of more obvious necrosis with complete disruption of tissue architecture. After 31 days, ablated regions demonstrated complete apparent resorption of ablated tissue with formation of cystic regions containing fluid. The inherent cooling of the urethra using the technique resulted in complete urethral preservation in all cases.

CONCLUSIONS

Prostatic ablation of zones of size and shape corresponding to human BPH is possible using appropriate transurethral applicators using MRTI, and ablated tissue may be depicted clearly in contrast-enhanced magnetic resonance images. The ability accurately to monitor prostate tissue heating, the apparent resorption of ablated regions over 1 month, and the inherent urethral preservation suggest that the magnetic resonance-guided techniques described are highly promising for the in vivo ablation of symptomatic human BPH.

Revival of thermotherapy for benign prostatic hyperplasia

PURPOSE OF REVIEW

Transurethral resection of the prostate (TURP) has long been held as the gold standard for treatment of benign prostatic hyperplasia (BPH); however, there has been significant innovation in other less invasive alternative treatments for BPH in recent years. BPH treatment guidelines now recommend minimally invasive therapy be considered as a treatment option alongside TURP and medical management. Our purpose is to review the current evidence supporting the safety, effectiveness, and durability of transurethral microwave thermotherapy (TUMT) as a minimal invasive technique.

RECENT FINDINGS

Recent clinical studies of TUMT have provided significant evidence regarding safety, efficacy, and durability. TUMT has now become a minimally invasive office-based alternative to both standard TURP and medical therapy in the treatment of bladder outlet obstruction and lower urinatry tract symptoms due to BPH.

SUMMARY

TUMT treatment has improved with the advent of later generation devices. This well tolerated, effective, and durable therapy for the treatment of BPH has definitively found its place as one of the alternatives to TURP. Anestheisa-free outpatient capability, lack of sexual side-effects, and avoidance of actual surgery are attractive to patient and clinician alike. TUMT deserves reconsideration in clinical practices as a suitable treatment alternative to TURP and medical therapy.

Adverse events of extracorporeal ultrasound-guided high intensity focused ultrasound therapy

Background

High-intensity focused ultrasound (HIFU) is considered to be an alternative to surgery. Extracorporeal ultrasound-guided HIFU (USgFU) has been clinically used to treat solid tumors. Preliminary trials in a small sample of a Western population suggested that this modality was safe. Most trials are performed in China thereby providing comprehensive data for understanding the safety profile. The aim of this study was to evaluate adverse events of USgFU therapy.

Methods and Findings

Clinical data were searched in 2 Chinese databases. Adverse events of USgFU were summarized and compared with those of magnetic resonance-guided HIFU (MRgFU; for uterine, bone or breast tumor) and transrectal ultrasound-guided HIFU (for prostate cancer or benign prostate hyperplasia). USgFU treatment was performed using 7 types of device. Side effects were evaluated in 13262 cases. There were fewer adverse events in benign lesions than in malignant lesions (11.81% vs. 21.65%, p<0.0001). Rates of adverse events greatly varied between the disease types (0–280%, p<0.0001) and between the applied HIFU devices in both malignant (10.58–44.38%, p<0.0001) and benign lesions (1.67–17.57%, p<0.0001). Chronological analysis did not demonstrate a decrease in the rate of adverse events. Based upon evaluable adverse events, incidences in USgFU were consistent with those in MRgFU or transrectal HIFU. Some side effects frequently occurred following transrectal HIFU were not reported in USgFU. Several events including intrahepatic metastasis, intraoperative high fever, and occlusions of the superior mesenteric artery should be of particular concern because they have not been previously noted. The types of adverse events suggested that they were ultrasonic lesions.

Conclusion

The frequency of adverse events depended on the location of the lesion and the type of HIFU device; however, side effects of USgFU were not yet understood. USgFU did not decrease the incidence of adverse events compared with MRgFU.

Ablation of benign prostatic hyperplasia using microbubble-mediated ultrasound cavitation

Benign prostatic hyperplasia (BPH) is a world-wide common disease in elderly male patients. A number of invasive physiotherapies have been used to replace prostatectomy. In this article we report our hypothesis of using microbubbles-mediated ultrasound cavitation effects to ablate prostatic tissues. Microbubble ultrasound contrast agent is widely used contrast media in ultrasonography, yet it is also found to act as cavitation nuclei or enhancer. Once excited by a high peak pressure ultrasound pulse, the mechanical effects, like shock wave and microstream, released from cavitation could produce a series of bioeffects, contributing to sonoporation, microvascular rupture and hematoma. BPH is known to have hyperplastic neovasculature and this make it possible to be disrupted by the physical effects of cavitation under existing microbubbles in circulation. Mechanical ablation of prostatic capillary or small vessels could result in pathological alterations such as thrombosis, micro-circulation blockage, prostatic necrosis and atrophia. Thereupon it could effectively treat BPH by nontraumatic ways.

The effect of high intensity focused ultrasound on luciferase activity on two tumor cell lines in vitro, under the control of a CMV promoter

In this study, we compared the effect of high intensity focused ultrasound (HIFU) and thermal stress on the luciferase activity, controlled by a cytomegaly virus (CMV) promoter in an in vitro model using two tumor cell lines (M21, SCCVII). HIFU was applied in a pulsed-wave mode with increasing voltage at constant pulse duration, or thermal stress was delivered over a range of temperatures (36-52 degrees C) for 5 min. The resulting luciferase activity was measured in live cells using a cooled CCD camera. Luciferase activity was measured at set time intervals over a total of 48 h post-stress. Compared to baseline, the luciferase activity of the M21 tumor cell line when exposed to HIFU was approximately 54.2+/-67.5% (p<0.01) higher at a temperature of 42 degrees C, and approximately 52.9+/-128.5% (p<0.01) higher at 44 degrees C. In the SCCVII tumor cell line, the luciferase activity after HIFU application was 55.4+/-66.6% (p<0.01) higher compared to baseline at a temperature of 42 degrees C. The M21 and SCCVII tumor cell line when exposed to thermal stress alone did not increase the luciferase activity. M21 and SCCVII tumor cells exposed to HIFU showed a maximum decrease in cell viability to 45.3+/-7.5% and 10.3+/-7.5%, respectively, and when exposed to thermal stress to 85.3+/-3.5% and 20.4+/-6.5%, respectively, compared to the untreated control. In M21 and SCCVII cells exposed to HIFU, free radicals could be detected using the dichlorofluorescein dye. Our findings demonstrate that HIFU can enhance the luciferase activity controlled by a CMV promoter. However it also has a higher damaging effect on the cells.