Responders and non-responders to treatment of benign prostatic hyperplasia with transurethral microwave thermotherapy

Transurethral water vapor ablation of the prostate with the Rezūm system: Urodynamic findings

AIMS

The efficacy of the transurethral convective interstitial radiofrequency water vapor thermal ablation of the prostate with the Rezūm system for the treatment of male lower urinary tract symptom due to benign prostatic hyperplasia is well proven. The improvement of urodynamic parameters obtained from a simple uroflowmetry cannot measure the effect of water vapor injection on the bladder outlet obstruction.

METHODS

This monocentric retrospective pilot study analyzes the data of pressure-flow studies performed before and after 17 Rezūm procedures to answer the question whether thus obtained ablation of prostate tissue has a disobstructive effect on the bladder outlet.

RESULTS

All the functional outcomes were consistently improved after the procedure, with a median flowrate increase of 5.1 ml/s (p = 0.0022) and a median postvoid residual urine (PVR) reduction of 100 ml (p = 0.0042). The prostate volume was reduced by 40% (p < 0.0001) and the median Bladder Outlet Obstruction Index (BOOI) reduction was 53.8 (p < 0.0001).

CONCLUSIONS

These data show that the possibility to significantly reduce the obstruction grade with even a single Rezūm procedure is concrete and seems to be independent from the degree of the obstruction grade.

Treatment Characteristics and Inherent Prostatic Features Do Not Predict Patient Outcome after High-Energy Transurethral Thermotherapy: A Prospective Study of ProstaLund Feedback Treatment™

PURPOSE

To determine whether treatment characteristics, intrinsic prostatic factors, and clinical parameters predict the outcome in patients treated with high-energy transurethral microwave thermotherapy (HE-TUMT).

PATIENTS AND METHODS

A series of 48 consecutive patients, 28 with an indwelling catheter, underwent ProstaLund Feedback Treatment (PLFT). The 12-month International Prostate Symptom Score response rate (IPSS < or = 7 or > or =50% improvement), peak flow rate response rate (Q(max) > or = 15 mL/sec or > or =50% improvement), and bladder outflow obstruction index response rate (BOOI <40) were correlated with treatment characteristics such as duration, average intraprostatic temperature, time with therapeutic intraprostatic temperatures (>45 degrees C), average intraprostatic blood flow, consumed energy, and recorded prostate mass destruction. Baseline parameters such as age, serum prostate specific antigen concentration, prostate volume, and pretreatment IPSS, quality of life (QOL), Q(max), postvoiding residual urine volume (PVR), and BOOI were included in the logistic regression analysis.

RESULTS

Treatment characteristics did not discriminate responders and nonresponders to HE-TUMT. For the patients without a catheter, the IPSS response (75%) was predicted by higher pretreatment IPSS (P = 0.041; relative risk [RR] = 3.4) and higher pretreatment PVR (P = 0.026; RR = 1.1). The Q(max) response (85%) was predicted by higher grades of pretreatment obstruction (P = 0.009; RR = 1.02). The BOOI response (60%) was not related to any of the factors tested. For the patients with a catheter, no outcome predictors could be identified.

CONCLUSIONS

According to our results, the intraprostatic temperature, the duration of intraprostatic temperatures in the therapeutic range, and the pattern of blood flow did not predict HE-TUMT outcome. Treatment duration, consumed energy, and the magnitude of tissue necrosis did not translate into clinical efficacy. Clinical parameters were important predictors of outcome in patients not in retention.

Efficacy and safety of intraprostatic temperature-controlled microwave thermotherapy in patients with benign prostatic hyperplasia: results of a prospective, open-label, single-center study with 1-year follow-up

BACKGROUND AND PURPOSE

Different devices for transurethral microwave thermotherapy (TUMT) are currently available for the treatment of benign prostatic hyperplasia (BPH). We evaluated the efficacy and safety of the Prostalund Feedback Treatment (PLFT), which continuously records the intraprostatic temperature, and its impact on sexual function of the patients.

PATIENTS AND METHODS

A total of 41 patients with lower urinary tract symptoms attributed to BPH were entered in this prospective open-label, single-center study of PLFT. The initial evaluation was performed according to a standard protocol. At 3, 6, and 12 months, the International Prostate Symptom Score (IPSS), bother score, sexual function, and peak flow rate (Qmax) were recorded. In addition, determination of prostate volume by transrectal ultrasonography (TRUS) and measurement of residual urine volume were repeated at the 6- and 12-month visits. All adverse events were also recorded. Patients with IPSS of < or =7, > or =50% improvement in IPSS from baseline, a Qmax of > or =15 mL/sec, or > or =50% improvement in Qmax from baseline were judged responders to the treatment.

RESULTS

Thirty-three of the patients completed the 12-month visit. The response rate was 88% (29 of 33 patients). There was a statistically significant decrease in IPSS at the 12-month visit, the mean IPSS being 7.1 v 21.9 at baseline (P<0.001). The mean IPSS was 10.3 and 7.6 at the 3- and 6-months' follow-up, respectively. The bother score presented a similar improvement, with a decrease from a mean of 4.2 at baseline to a mean of 1.4 after 12 months (P<0.001). The mean Qmax improved from 8.4 mL/sec at baseline to 15.9 mL/sec, 19.2 mL/sec, and 17.8 mL/sec at 3, 6, and 12 months, respectively (P<0.001). The mean change in prostate volume, as determined by TRUS, was 16 mL at 6 months and 19 mL at 12 months (P<0.001). The procedure was well tolerated. The mean post-treatment catheterization time was 17.90 days. Bladder spasms and urinary tract infection were the most common adverse events. Coitus ability remained practically unchanged after treatment (from 71% to 74.3%), but the number of patients with ejaculation decreased (from 78% to 51.4%).

CONCLUSION

Our results indicate that PLFT is an effective and safe treatment for most patients with BPH.

Transurethral microwave thermotherapy for benign prostatic hyperplasia

Transurethral resection of the prostate (TURP) remains the gold standard for treatment of benign prostatic hyperplasia (BPH). In general, while this procedure is safe, patients require a spinal, epidural, or general anesthesia and often several days of hospital stay; the potential morbidity and mortality limits the use of TURP in high-risk patients. Pharmacotherapy has been recommended as a first-line therapy for all patients with mild to moderate symptoms. Patients are often times enthusiastic if they are offered a one-time method to treat lower urinary tract symptoms secondary to BPH, provided that the method offers reduced risk and allows an efficacy equal to that of medical therapy. One such method is transurethral microwave thermotherapy (TUMT). TUMT involves the insertion of a specially designed urinary catheter with a microwave antenna, which heats the prostate and destroys hyperplastic prostate tissue. TUMT allows the avoidance of general or regional anesthesia, and results in minimal blood loss and fluid absorption. In this review, the authors discussed the current indications and outcome of TUMT, including the history of the procedure, the mechanism of action, the indications for TUMT, the pre-operative considerations, the patient selection, the results in terms of efficacy, by comparing TUMT vs. Sham, TUMT vs. Alpha-blocker and TUMT vs. TURP. Finally, the complications are presented, as well as other uses and future directions of the procedure. The authors concluded that TUMT is a safe and effective minimally invasive alternative to treatment of symptomatic BPH.

Transurethral microwave thermotherapy (TUMT) with the Targis System: a single-centre study on 78 patients with acute urinary retention and poor general health

OBJECTIVES

To evaluate the Targis System in men presenting with acute urinary retention, high prostate volume and high operative risk.

MATERIALS AND METHODS

Between August 1997 and March 2001, a total of 78 patients in poor general health status presenting with large prostate glands and acute urinary retention secondary to BPH were treated with the Targis TUMT device. Mean age, mean prostate volume, and the percentage of patients who were able to urinate spontaneously after the procedure as well as mean peak and average flow rates and mean residual urine volume were evaluated.

RESULTS

68 (87.1%) of the 78 patients were able to urinate spontaneously three months after the procedure. In 5 (7.3%) of the 68 patients urinary retention recurred within two years. Following treatment, the mean peak flow rate in the 68 successfully treated patients was 11.1 ml/s, while the mean postvoid residual volume was 46 ml.

CONCLUSION

Based on these data we recommend transurethral thermotherapy using the Targis System for patients in poor general health presenting with urinary retention and prostate volumes of more than 35 cc in whom TURP is not possible.

Microwave thermotherapy for benign prostatic hyperplasia with the Dornier Urowave: response durability and variables potentially predicting response

OBJECTIVES

To evaluate the clinical efficacy and durability of transurethral microwave thermotherapy (TUMT) in the treatment of benign prostatic hyperplasia. The clinical variables useful in predicting outcome were identified.

METHODS

From October 1996 to March 2000, 58 patients with symptomatic benign prostatic hyperplasia were treated with TUMT using the Urowave device. Treatment outcome was evaluated by the International Prostate Symptom Score (IPSS), quality-of-life assessment score, and urodynamic investigation. The patients were divided into those having a good and poor response on the basis of the degree of IPSS decrease at 3 months.

RESULTS

The mean IPSS significantly decreased from 19.2 at baseline to 13.3 at 3 months (P <0.0001). The mean quality-of-life score changed from 4.6 at baseline to 2.9 at 3 months (P <0.0001). No statistically significant differences in peak flow rate, postvoid residual volume, Schäfer's obstruction scale, or detrusor pressure at peak flow were noted before or after TUMT. The pretreatment IPSS of the good response group was significantly higher than that of the poor response group (P=0.017). A more significant difference was obtained for the obstructive score (P = 0.002), and no difference was observed in the irritative score (P = 0.631). The Schäfer grading scale score of the good response group was significantly smaller than that of the poor response group (P = 0.047).

CONCLUSIONS

TUMT with the Urowave was effective in eliminating symptoms associated with benign prostatic hyperplasia, but did not markedly improve the objective voiding parameters. Patients with urodynamically less obstructive symptoms but subjectively more obstructive symptoms are therefore probably good candidates for TUMT.

Intra-prostatic vasculature studies: can they predict the outcome of transurethral microwave thermotherapy for the management of bladder outflow obstruction?

BACKGROUND

Blood perfusion regulates intraprostatic temperatures during transurethral microwave thermotherapy (TUMT). We evaluated baseline intraprostatic vasculature, as a predictor of efficacy of TUMT.

METHODS

Twenty-two patients, with lower urinary tract symptoms (LUTS) suggestive of bladder outflow obstruction, were treated with TUMT (Prostatron). At baseline, three-dimensional contrast-enhanced power-flow-Doppler prostate ultrasonography (3D-CE-PFD) was performed. Assuming that the percentage of perfused area (PPA) is a realistic measure of blood flow, it was used to quantify intraprostatic vasculature.

RESULTS

The median (range) age, prostate size, and energy delivered were 66 years (48-80), 47 cm(3) (30-121), 110 kJ (29-136), respectively. The response was 77% (5 failures). The median (range) PPA was 2.76% (0.7-11.3). No difference in PPA among good and poor responders was detected nor was any correlation between PPA and baseline parameters.

CONCLUSIONS

The baseline intraprostatic vascularization, documented by CE-PFD studies, has no predictive value for the efficacy of TUMT. It seems that "static" baseline blood flow does not reflect the "dynamic" thermoregulatory role of blood flow during treatment.

Predictors of treatment outcome for high-energy transurethral microwave thermotherapy

BACKGROUND AND PURPOSE

Transurethral microwave thermotherapy (TUMT) is an innovative alternative to transurethral resection of the prostate (TURP) for the treatment of lower urinary tract symptoms (LUTS) suggestive of bladder outflow obstruction (BOO). Although the results are satisfactory for the majority of the patients, a considerable number of patients have an unfavorable outcome. Thus, the identification of features able to predict efficacy of TUMT for individual candidates is an important issue.

MATERIALS AND METHODS

The available literature in MEDLINE covering the predictive role of various baseline measures for the outcome of high-energy TUMT was reviewed. Direct comparison among various studies was not possible because of differences in thermotherapy devices, treatment protocols, and the definition of a good response to treatment.

RESULTS

Predictive features have been detected only for the Prostatron device. A small prostate volume, a low grade of BOO, and advanced age were independent predictors of poor outcome. The strongest predictive feature was the amount of energy delivered during treatment. Histologic characteristics (epithelial:stromal ratio and microvessel density) have not proved predictive for therapeutic outcome. The role of intraprostatic vascularization, as a regulator of the temperature during treatment, seems to be of the greatest importance, but results have not been presented yet.

CONCLUSION

The value of baseline clinical measures for the selection of the best candidates for TUMT is limited at best. Variations in the internal structure of the individual prostate seem to play the most important role in regulating the amount of energy absorbed during treatment, and further research must focus on this item.

Transurethral microwave thermotherapy: how does it work?

Although some authors have proposed that the favorable impact of transurethral microwave thermotherapy (TUMT) for benign prostatic hyperplasia has only a placebo effect, this idea is inconsistent with the findings of a number of sham-controlled clinical trials. Histologic and immunohistochemical studies have shown that the nerve fibers in the periurethral tissue are damaged or ablated by TUMT, and it appears that the heat affects the innervation of the smooth muscle cells. Among the nerves damaged are the sensory neurons of the posterior urethra, and this change might reduce the excitatory signals from the urethrodetrusor facilitating reflexes. Necrosis and apoptosis within a limited area also have been described. Thus, there is likely more than one basis for the therapeutic effect of TUMT.

Elevation of sensory thresholds in the prostatic urethra after microwave thermotherapy

OBJECTIVES

To determine whether transurethral microwave thermotherapy (TUMT) affects the sensory threshold in the posterior urethra and whether such an effect influences urinary storage symptoms.

PATIENTS AND METHODS

The sensory threshold was measured before and at 3 and 12 weeks after TUMT in 13 men with minor obstructive symptoms caused by benign prostatic hyperplasia. Sensations were evoked by electrical stimulation at different frequencies, using a bipolar ring-electrode mounted on a urethral catheter. Changes in sensory thresholds were evaluated in the patients both as a group and individually. The patients were interviewed about their symptoms at each measurement.

RESULTS

After TUMT, 12 patients were satisfied and reported decreased irritative symptoms, primarily less frequent nocturnal micturition; two patients were cured of urgency incontinence. In 11 of the satisfied patients, and the unsuccessful patient, decreased urge accompanied increased sensory thresholds. Thresholds elevated by >/= 30% were correlated with decreased irritative symptoms.

CONCLUSIONS

TUMT decreases sensitivity in the posterior urethra, which may alleviate storage symptoms.

Transurethral microwave thermotherapy in benign prostatic hyperplasia

This article reviews the available literature and data on high-energy transurethral microwave therapy (TUMT) in the treatment of benign prostatic hyperplasia (BPH) causing lower urinary tract symptoms (LUTS). TUMT is a safe, durable, (1-hour) procedure, without the need for anesthesia. Emphasis is made on the effect and mechanism of TUMT, the different devices available including different energy protocols, and accompanying clinical results.

Denervation of periurethral prostatic tissue by transurethral microwave thermotherapy

PURPOSE

To determine whether transurethral microwave thermotherapy (TUMT) affects innervation of the urethra and periurethral prostate.

MATERIAL AND METHODS

Ten patients with troublesome benign prostatic hyperplasia (BPH) were treated with TUMT 1 week prior to transurethral resection of the prostate (TURP). At surgery, a biopsy was taken for histological examination and for immunohistochemical staining of the non-specific neuromarker protein gene product (PGP) 9.5. Control material consisted of identical biopsies from 10 patients undergoing TURP because of BPH, but not subjected to TUMT prior to surgery.

RESULTS

Histological examination revealed well-preserved, non-necrotic tissues in all biopsies. Nerve fibres were completely or almost absent in the smooth muscle layer in all but one of the TUMT cases, whereas all non-TUMT patients exhibited large numbers of nerve fibres in the smooth muscle layer.

CONCLUSIONS

TUMT does affect innervation of the urethra and periurethral prostatic tissue.

Pretreatment prostate-specific antigen as an outcome predictor of targeted transurethral microwave thermotherapy

OBJECTIVES

To evaluate pretreatment serum prostate-specific antigen (PSA) as an outcome predictor of targeted microwave thermotherapy.

METHODS

Seventy-one patients with lower urinary tract symptoms of benign prostatic hyperplasia underwent targeted transurethral microwave thermotherapy using the Targis system. Outcomes 12 months after treatment were evaluated by the International Prostate Symptom Score (IPSS), peak urinary flow rate (Qmax), and quality-of-life (QOL) score. The ability of PSA to predict outcomes was evaluated by linear and logistic regression and receiver operating characteristic curve analysis.

RESULTS

Higher pretreatment PSA levels were significantly predictive of an absolute IPSS change of -7.5 or less for patients with moderate baseline symptoms or - 15 or less for those with severe baseline symptoms; an absolute Qmax change of 5 mL/s or greater; an absolute QOL score change of -3 or less; an IPSS at 12 months of 7 or less; a Qmax at 12 months of greater than 12 mL/s; and a QOL score at 12 months of 1 or less. Nevertheless, even without taking pretreatment PSA into account, most patients benefitted substantially from targeted microwave thermotherapy. Thus, 74%, 71%, and 79% of all eligible patients improved 50% or more in IPSS, Qmax, and QOL score, respectively, at 12 months compared with baseline. No significant association between PSA and either prostate or transition zone volume could be demonstrated.

CONCLUSIONS

Most patients benefit substantially from targeted microwave thermotherapy. However, higher PSA levels are significantly predictive of more favorable outcomes. This association may reflect patient-to-patient differences in the relative abundance of PSA-producing epithelial cells in the transition zone of the prostate.

Importance of thermal dose and antenna location in transurethral microwave thermotherapy for benign prostatic hyperplasia

The importance of thermal dose and the location of the heat maximum for the outcome of transurethral microwave thermotherapy for benign prostatic hyperplasia was studied. It was originally designed as a two-arm randomized study of 196 patients comparing high and low effect with the heat maximum at the apex of the prostate. The inclusion criteria were: prostate volume 25 to 70 cc, Madsen score > or = 8, Qmax < or = 15 mL/sec, residual urine volume < 350 mL, and no median-lobe enlargement. Using the same inclusion criteria, another group of 31 patients was compared in which the location of the heat maximum was at the base of the prostate. Treatment was performed as an outpatient single session procedure for 70 minutes with the Prostcare (Bruker Medical, France). Improvement was found after 6 months in all three groups regarding Qmax and Madsen, bother, and quality of life scores. The improvement of Madsen score from baseline was more pronounced in the high-effect base group than in the other two groups. Responders were defined as patients showing improvement in Madsen score who were satisfied with treatment outcome and in no need of complementary treatment at 6 months' follow-up. Significantly more responders were found, and the increment of serum prostate specific antigen and side effects were more pronounced, in the high-effect base group than in the other two groups. Treatment outcome seems to be both dose related and dependent on the location of the heat maximum. However, the improvement in outcome is associated with increased morbidity.

Pressure-flow studies before and after transurethral microwave thermotherapy of benign prostatic hyperplasia using low- and high-energy protocols

OBJECTIVE

To compare pressure-flow results before and 3 months after transurethral microwave thermotherapy (TUMT) for benign prostatic hyperplasia (BPH), performed with lower and higher energy protocols.

PATIENTS AND METHODS

Twenty-four patients were treated using a high-energy protocol performed with a heatshock strategy, i.e. a rapid increase in intraprostatic temperatures to a maximum of 55-67 degrees C. A helical antenna was used which produced maximum heating at the base of the prostate. A further 25 patients were treated using a lower energy protocol with a slow increase in intraprostatic temperatures to a maximum of 45-53 degrees C. A first-generation filament antenna was used with the maximum heat produced at the prostatic apex. All treatments were performed as single-session outpatient procedures of 60-70 min duration.

RESULTS

There was a significantly greater improvement in pressure-flow variables, i.e. maximum urinary flow rate, detrusor pressure at maximum flow and minimal urethral opening pressure, in those treated with higher energy TUMT than in those receiving the lower energy protocol. The Madsen and quality-of-life scores, and maximum urinary flow rate on uroflowmetry, were also significantly better in the higher energy group.

CONCLUSION

Higher energy TUMT performed using a heat-shock strategy provides a better pressure-flow outcome than lower energy thermotherapy. Compared with previously published results, the outcome after higher energy TUMT is at least similar to other treatment alternatives for BPH.

Tolerability of high energy transurethral microwave thermotherapy with topical urethral anesthesia: results of a prospective, randomized, single-blinded clinical trial

PURPOSE

We determine the tolerability of high energy transurethral microwave thermotherapy with topical urethral anesthesia alone without supplementary systemic sedoanalgesia.

MATERIALS AND METHODS

A total of 45 patients with symptomatic benign prostatic hyperplasia were randomized to high energy transurethral microwave thermotherapy using either topical urethral anesthesia alone (topical anesthesia group) or topical anesthesia with adjunctive intravenous sedoanalgesia (sedoanalgesia group). Pain was evaluated sequentially by means of a 0 to 10 visual analog scale score. Posttreatment followup included determinations of International Prostate Symptom Score, peak flow rate, post-void residual urine, and quality of life score at 6 and 12 weeks.

RESULTS

Upon commencement of microwave treatment mean visual analog scale score was 1.3 (95% confidence interval [CI], 1.0 to 1.7) in the sedoanalgesia group and 1.4 (95% CI, 1.0 to 1.9) in the topical anesthesia group. During therapy visual analog scale score increased to a peak at 30 minutes of 2.0 (95% CI, 1.6 to 2.4) and 2.2 (95% CI, 1.7 to 2.6) in the sedoanalgesia and topical anesthesia groups, respectively. Thereafter, visual analog scale score continuously declined, falling to 0.1 (95% CI, 0.0 to 0.2) and 0.2 (95% CI, 0.0 to 0.3) in the 2 respective groups by 1 hour following conclusion of the treatment period. There was no statistically significant difference between the groups in the treatment profile of visual analog scale scores (p = 0.701). Significant posttreatment improvements were demonstrated in International Prostate Symptom Score, peak flow rate, post-void residual urine and quality of life scores but there were no significant differences between the groups in the magnitude of improvement in these outcome measures.

CONCLUSIONS

High energy transurethral microwave thermotherapy is well tolerated by patients under topical anesthesia alone and, therefore, can be administered in the outpatient setting without potent medications that necessitate intensive patient monitoring, pose risks for side effects and add to treatment costs.

Temperature controlled high energy transurethral microwave thermotherapy for benign prostatic hyperplasia using a heat shock strategy

PURPOSE

We evaluate the clinical outcome of temperature controlled high energy transurethral microwave thermotherapy for benign prostatic hyperplasia using heat shock strategy.

MATERIALS AND METHODS

A total of 32 patients were evaluated 3, 6 and 12 months after thermotherapy according to symptom scores, uroflowmetry, residual urine volume, sexual functions and side effects.

RESULTS

At 12 months symptom score and maximum flow rate had improved 79% from 13.5 to 2.9, and 71% from 10.0 to 17.1 ml. per second, respectively. Furthermore, bother and quality of life scores and residual and voided urine volumes had improved significantly. However, a higher morbidity than previously shown after lower energy protocols was demonstrated. Treatment influenced sexual functions, especially ejaculation quality, and after treatment 29% of the patients had anejaculation. Significantly less energy was required for prostate volumes 40 ml. or greater to reach the same intraprostatic temperature level as those less than 40 ml. as demonstrated by radiometry.

CONCLUSIONS

High energy transurethral microwave thermotherapy using a heat shock strategy is an effective treatment for benign prostatic hyperplasia and produces a better outcome than shown with lower energy protocols. However, the morbidity is not negligible and ejaculation quality is affected. Less relative energy is needed for large than small prostate volumes to reach the same intraprostatic temperature level as demonstrated by radiometry.

Tolerability of high energy transurethral microwave thermotherapy with topical urethral anesthesia: results of a prospective, randomized, single-blinded clinical trial

PURPOSE

We determine the tolerability of high energy transurethral microwave thermotherapy with topical urethral anesthesia alone without supplementary systemic sedoanalgesia.

MATERIALS AND METHODS

A total of 45 patients with symptomatic benign prostatic hyperplasia were randomized to high energy transurethral microwave thermotherapy using either topical urethral anesthesia alone (topical anesthesia group) or topical anesthesia with adjunctive intravenous sedoanalgesia (sedoanalgesia group). Pain was evaluated sequentially by means of a 0 to 10 visual analog scale score. Posttreatment followup included determinations of International Prostate Symptom Score, peak flow rate, post-void residual urine, and quality of life score at 6 and 12 weeks.

RESULTS

Upon commencement of microwave treatment mean visual analog scale score was 1.3 (95% confidence interval [CI], 1.0 to 1.7) in the sedoanalgesia group and 1.4 (95% CI, 1.0 to 1.9) in the topical anesthesia group. During therapy visual analog scale score increased to a peak at 30 minutes of 2.0 (95% CI, 1.6 to 2.4) and 2.2 (95% CI, 1.7 to 2.6) in the sedoanalgesia and topical anesthesia groups, respectively. Thereafter, visual analog scale score continuously declined, falling to 0.1 (95% CI, 0.0 to 0.2) and 0.2 (95% CI, 0.0 to 0.3) in the 2 respective groups by 1 hour following conclusion of the treatment period. There was no statistically significant difference between the groups in the treatment profile of visual analog scale scores (p = 0.701). Significant posttreatment improvements were demonstrated in International Prostate Symptom Score, peak flow rate, post-void residual urine and quality of life scores but there were no significant differences between the groups in the magnitude of improvement in these outcome measures.

CONCLUSIONS

High energy transurethral microwave thermotherapy is well tolerated by patients under topical anesthesia alone and, therefore, can be administered in the outpatient setting without potent medications that necessitate intensive patient monitoring, pose risks for side effects and add to treatment costs.

Temperature controlled high energy transurethral microwave thermotherapy for benign prostatic hyperplasia using a heat shock strategy

PURPOSE

We evaluate the clinical outcome of temperature controlled high energy transurethral microwave thermotherapy for benign prostatic hyperplasia using heat shock strategy.

MATERIALS AND METHODS

A total of 32 patients were evaluated 3, 6 and 12 months after thermotherapy according to symptom scores, uroflowmetry, residual urine volume, sexual functions and side effects.

RESULTS

At 12 months symptom score and maximum flow rate had improved 79% from 13.5 to 2.9, and 71% from 10.0 to 17.1 ml. per second, respectively. Furthermore, bother and quality of life scores and residual and voided urine volumes had improved significantly. However, a higher morbidity than previously shown after lower energy protocols was demonstrated. Treatment influenced sexual functions, especially ejaculation quality, and after treatment 29% of the patients had anejaculation. Significantly less energy was required for prostate volumes 40 ml. or greater to reach the same intraprostatic temperature level as those less than 40 ml. as demonstrated by radiometry.

CONCLUSIONS

High energy transurethral microwave thermotherapy using a heat shock strategy is an effective treatment for benign prostatic hyperplasia and produces a better outcome than shown with lower energy protocols. However, the morbidity is not negligible and ejaculation quality is affected. Less relative energy is needed for large than small prostate volumes to reach the same intraprostatic temperature level as demonstrated by radiometry.

How to select patients suitable for transurethral microwave thermotherapy: a systematic evaluation of potentially predictive variables

OBJECTIVE

To identify clinical variables useful in predicting outcome after transurethral microwave thermotherapy (TUMT) of the prostate with Prostasoft v. 2.0.

PATIENTS AND METHODS

Thirty-eight men with symptomatic benign prostatic hyperplasia (BPH) were treated with TUMT using the Prostatron device with the low-energy (v. 2.0) software. Before and 6 months after treatment symptoms were evaluated using the Madsen-Iversen (M-I) symptom score, a clinical examination and suprapubic pressure-flow measurement, free urinary peak flow rate (Qmax) and determination of post-void residual urine volume (PVR). Bladder outlet obstruction was assessed from urodynamic pressure-flow studies using the classification of Abrams and Griffiths, the obstruction grading of Schäfer, and calculation of other published factors, e.g. the urethral resistance, an obstruction index and the detrusor adjusted mean passive urethral resistance factor (DAMPF). Categories of M-I score (total, irritative and obstructive), PVR and Qmax were investigated to determine whether any could predict the outcome after low-energy TUMT. The values after treatment and changes in Qmax, M-I score and PVR were used as efficacy variables.

RESULTS

Variables describing infravesical obstruction had predictive characteristics that may be useful in selecting patients for TUMT v. 2.0 and significantly better results were obtained in patients with a low to moderate obstruction as graded using the DAMPF classification of obstruction. The results also indicated that patients with a high irritative M-I score or a Qmax of 7-14 mL/s were those who fared best after TUMT.

CONCLUSIONS

Variables expressing the obstruction grade seem to be useful in predicting outcome after TUMT (v. 2.0). Patients with a high obstruction index are probably unsuitable for TUMT (v. 2.0).

High energy thermotherapy versus transurethral resection in the treatment of benign prostatic hyperplasia: results of a prospective randomized study with 1 year of followup

PURPOSE

We compared the outcome of transurethral resection of the prostate and high energy microwave thermotherapy in patients with benign prostatic hyperplasia.

MATERIALS AND METHODS

Of 52 patients with symptomatic benign prostatic hyperplasia 21 (mean age plus or minus standard deviation 69.6 +/- 8.5 years) were treated with transurethral resection of the prostate and 31 (mean age 69.3 +/- 5.9 years) were treated with high energy microwave thermotherapy. Patients were assessed using the Madsen symptom score, measurements of voiding parameters, transrectal ultrasound and cystometry, including pressure-flow analyses. Examinations were repeated at fixed intervals for up to 12 months after treatment.

RESULTS

After transurethral resection and thermotherapy there was significant improvement in all clinical parameters. At 1 year of followup symptomatic improvement was 78% in the transurethral resection group versus 68% in the thermotherapy group, with improvements in free flow rate of 100 and 69%, respectively. Both groups had significant relief of bladder outlet symptoms. No serious complications occurred in either group, while 1 patient in each group required repeat treatment.

CONCLUSIONS

Satisfactory results were obtained after both treatments, with improvements following high energy microwave thermotherapy being in the same range as those after transurethral resection of the prostate.

Current status of thermotherapy of the prostate

PURPOSE

We reviewed the available data on transurethral microwave thermotherapy in the treatment of patients with benign prostatic hyperplasia (BPH). Furthermore we provide a perspective of this minimally invasive treatment modality.

MATERIALS AND METHODS

To our knowledge all previously reported data from clinical trials of transurethral microwave thermotherapy for BPH are reviewed.

RESULTS

Transurethral microwave thermotherapy was designed to apply microwave energy deep within lateral prostatic lobes while simultaneously cooling the urethral mucosa, thus enabling an outpatient based anesthesia-free procedure. Lower energy protocols using the Prostraton device provide significant symptomatic improvement and improvement in maximum flow of approximately 35% over baseline. Similar changes are being documented with other transurethral microwave thermotherapy devices. Higher energy protocols using the Prostatron device result in symptomatic improvement similar to that of lower energy protocols, while improvement in uroflowmetry is much more pronounced. However, the latter effect is achieved at the expense of increased morbidity. Second generation protocols have not yet been documented by users of the other thermotherapy devices.

CONCLUSIONS

Numerous studies unequivocally support the efficacy and safety of transurethral microwave thermotherapy for treatment of symptomatic BPH. Significant improvement in objective and subjective parameters has been realized with transurethral microwave thermotherapy at multiple centers in the United States and Europe.

Transrectal ultrasonography to predict the clinical outcome of transurethral microwave thermotherapy in patients with benign prostatic hyperplasia

BACKGROUND

This study evaluated the long-term efficacy of transurethral microwave thermotherapy (TUMT) in the treatment of benign prostatic hyperplasia (BPH), and determined whether the indices obtained with transrectal ultrasonography (TRUS) can predict the clinical response to TUMT.

METHOD

Between November 1991 and June 1992, 43 patients with symptomatic BPH were treated with TUMT using the Prostcare device. The therapy consisted of a 1-hour treatment under topical anesthesia. The findings of uroflowmetry and AUA symptom score before treatment were compared with those obtained at each visit after the therapy. As the indices, the transition zone (TZ) volume, transition zone ratio (TZ ratio = TZ volume/total prostate volume), total prostate volume, and presumed circle area ratio (PCAR) were calculated.

RESULTS

There was a significant correlation between pretreatment TZ ratio and residual urine volume (r = 0.472, P = 0.0022). The efficacy rates calculated by response criteria on the 3 point scale at 2 months, 12 months, and 30 months were 44.2%, 30.2%, and 25%, respectively. The significant prognostic factors that predicted the clinical effect 1 year after treatment were the TZ ratio and intraprostatic temperature. After controlling for the treatment temperature, the multivariate logistic regression model demonstrated that the TZ ratio was the significant predictor (P = 0.049) of 1 year efficacy of treatment.

CONCLUSION

The present study showed that the efficacy rate of TUMT at 30 months was 25%, and that TRUS provides a simple parameter, the TZ ratio, which predicts the efficacy of TUMT.

Transurethral microwave thermotherapy for benign prostatic hyperplasia. Subjective response and urodynamic changes

Results of transurethral microwave thermotherapy for benign prostatic hyperplasia were good after 1 year in 68% of 66 cases. Despite good correlation between subjective assessment of results and improvement in urodynamic parameters, no predictive factors for probably successful outcome could be identified. Diminution in frequency of micturition (diurnal from 8.8 to 6.8 times, nocturnal from 3.0 to 1.6 times), increased flow rates (Q max from 8.8 to 14.2 ml/s) and reduction of detrusor pressures during voiding (Pdet max from 86.9 to 75.0 cm H2O) were significant, but the change in residual volume (from 52 to 37 ml) was of lesser degree (all mean values). Transurethral microwave thermotherapy can be tried for relief of moderate obstruction when transurethral prostatic resection involves risk, or the patient himself requests noninvasive treatment.

Serum concentrations of prostate-specific antigen after diagnostic procedures and transurethral microwave thermotherapy of benign prostatic hyperplasia

The objective was to study the effects of diagnostic and therapeutic procedures on serum prostate-specific antigen (PSA) concentration. Urethrocystoscopy in combination with digital rectal examination was followed by a moderate increase of serum PSA for 7-10 days. At 1 day after transurethral microwave thermotherapy (TUMT), an acute and pronounced effect on PSA was observed, which returned to baseline level after 4 weeks. The initial rise in serum PSA corresponded to a PSA density of 1.11, compared to 0.07 at baseline. The present data should be taken into consideration in conjunction with endoscopic evaluation of the lower urinary tract. Additionally, the acute effect on PSA after TUMT strongly suggests the ability of thermotherapy to induce cellular injury and death. One-year follow-up, however, was associated with increased PSA levels, indicating that only a minor part of the PSA-producing compartment was lost in the acute phase.

Sexual function before and after transurethral microwave thermotherapy for benign prostatic hyperplasia

The effect of transurethral microwave thermotherapy (TUMT) for benign prostatic hyperplasia (BPH) on the ability of achieving erection and ejaculation was studied in one hundred and twenty patients. The patients underwent a single TUMT session for one hour without complementary treatment during the follow-up period of one year. A self-administered questionnaire on sexual functions was used. Our results showed that, despite individual reductions, there was an overall improvement in the ability to achieve erection. It was concluded that TUMT did not have any major adverse effects on sexual functions. However, it was not possible to predict that TUMT will improve sexual functions for the individual patient. Improvement of symptoms and a better quality of life may influence the results.