Long-term followup of randomized transurethral microwave thermotherapy versus transurethral prostatic resection study

PURPOSE

We evaluate the durable effect of high-energy transurethral microwave thermotherapy and transurethral prostatic resection for treatment of patients with lower urinary tract symptoms suggestive of bladder outflow obstruction.

MATERIALS AND METHODS

Between January 1996 and March 1997, 155 patients with lower urinary tract symptoms suggestive of bladder outflow obstruction were randomized to receive transurethral microwave thermotherapy (Prostatron*; device and commercial software) (82) or undergo transurethral prostatic resection (73). Initial patient evaluation was performed according to international standards. Patients were followed annually with the International Prostate Symptom Score (I-PSS) and uroflowmetry (maximum flow rate). The Kaplan-Meier survival analysis was used to calculate the cumulative risk of re-treatment, adjusted for loss to followup.

RESULTS

A total of 78 patients received transurethral microwave thermotherapy and 66 underwent transurethral prostatic resection. Median followup was 33 months. In the thermotherapy group mean maximum urinary flow rate improved from 9.2 ml. per second at baseline to 15.1, 14.5 and 11.9 ml. per second at 1, 2 and 3 years, and mean I-PSS decreased from 20 to 8, 9, and 12, respectively. In the resection group the corresponding numbers for maximum urinary flow rate were 7.8, 24.5, 23.0 and 24.7 ml. per second at 1, 2 and 3 years, and for I-PSS were 20, 3, 4 and 3, respectively. At 36 months, 14 patients in the thermotherapy and 8 from the resection groups underwent re-treatment, and the cumulative risk was 19.8% (95% confidence interval 10.4% to 29.3%) and 12.9% (4.5% to 21.3%), respectively (p = 0.28).

CONCLUSIONS

Transurethral microwave thermotherapy and transurethral prostatic resection achieve durable improvement in patients with lower urinary tract symptoms suggestive of bladder outflow obstruction, while the magnitude of improvement is higher with resection. The repeat thermotherapy is based on failure of therapy whereas repeat resection is based on complications of therapy.

Variability of pressure-flow studies in men with lower urinary tract symptoms

The objective of this study was to assess the short-term test-retest variability of pressure-flow studies (PFS) in men with lower urinary tract symptoms (LUTS). By choosing a short interval between two consecutive PFS, but notably not performing two tests within a single session, both tests represent the same routine testing procedure. Eighty-nine patients with LUTS suggestive of bladder outlet obstruction or detrusor underactivity, who received PFS, were asked to undergo a second urodynamic evaluation within 4 weeks after the initial test. At both visits, specialized physicians performed the PFS. Obstruction was quantified using the Abrams-Griffiths number (AG number). Each patient was classified as obstructed, unobstructed, or equivocally obstructed according to the International Continence Society nomogram. As expected, no systematic difference was observed in AG number between the first and the second visit at the group level. There was, however, considerable variation at the individual level. The average within-patient standard deviation was 14 cm H(2)O. This finding shows that if a patient's AG number is 30 at the first visit, his true AG number can be any value between 30 +/- 1.96 * 14 = 3 to 57, owing to random variability alone. The average within-patient standard deviation did not differ significantly between sub-groups of obstruction and other variables such as patient age, symptom score, prostate volume, or residual volume. The variability appeared to increase slightly with an increased interval between visits. Of all patients, 39% changed at least one category of obstruction at the second visit and 3% changed from definitely obstructed to definitely unobstructed or vice versa. We conclude that PFS cannot stand the test of serving as a gold standard to identify bladder outlet obstruction in patients with LUTS.

Efficacy and safety of the new high-energy 30-minute transurethral microwave thermotherapy: results of 1-year follow-up in a multicenter study

PURPOSE

To assess the efficacy and durability of a new 30-minute algorithm for high-energy transurethral microwave thermotherapy (TUMT, Prostasoft 3.5) in the treatment of men with lower urinary tract symptoms (LUTS) caused by benign prostatic hyperplasia.

MATERIALS AND METHODS

A total of 167 men (mean age 67 years) with bothersome LUTS were treated with the new TUMT protocol. Evaluation included assessment of the short- and long-term objective and subjective outcome measures of this treatment.

RESULTS

The treatment is well tolerated. The International Prostate Symptom Score improved from a mean of 19.2 at baseline to 7.9 at 12 months after treatment. Maximum urinary flow improved from 8.9 to 16.4 mL/s at 12 months. Mean duration of catheterization was 16.1 days. Urodynamic evaluation showed a change from the obstructed to the nonminimally obstructed zone. There were no serious complications.

CONCLUSION

High-energy TUMT using the new high-dose Prostasoft 3.5 protocol appears to be a safe, effective, and durable treatment. The faster procedure improves tolerance of the treatment. Subjective and objective improvements were significant and the treatment-related morbidity low.

A randomized study comparing high-energy TUMT to TURP: quality-of-life results

PURPOSE

To evaluate the impact of high-energy transurethral microwave thermotherapy (TUMT) and transurethral prostatic resection (TURP) on quality of life (QoL) in patients with benign prostatic hyperplasia (BPH).

MATERIALS AND METHODS

A total of 147 patients with BPH were randomized to receive either high-energy TUMT treatment (Prostasoft 2.5) or a TURP and were followed for 1 year. All patients completed a QoL questionnaire to assess perception of urinary difficulties, sexual function, daily activities, psychological well-being, social activities and improvement in QoL.

RESULTS

For almost all scales the standardized Cronbach's alpha was adequate. Between the various QoL scales there is a statistically significant correlation except for social well-being and sexual functions. There is also a significant correlation between the QoL scales and age, IPSS and Madsen. For the sexual functions there is only a correlation with age. A significant difference in improvement in favor of the TURP group was observed in general perception of urinary difficulties and activities of daily living. However, no difference between the groups was observed for the QoL scale measuring experienced improvement. The sexual function is not influenced by both treatment modalities. Both groups have a significant improvement in clinical outcome at all points of measurement. TURP has a better clinical outcome.

CONCLUSION

Both TUMT and TURP have a significant positive effect on various aspects of QoL. In particular, perception of urinary difficulties and activities of daily living are positively influenced by both treatments. TURP, however, has a greater impact than high-energy TUMT.

Intra- and inter-investigator variation in the analysis of pressure-flow studies in men with lower urinary tract symptoms

The objective of this study was to assess the intra- and inter-investigator variation in the analysis of pressure-flow studies that were performed in men with lower urinary tract symptoms. Two hospitals were involved in this study. In each hospital 100 PFS were selected. Photocopies of printouts of all PFS were analyzed manually by six experienced investigators, including determination of P(detQmax) and Q(max). Afterward, all 200 PFS were analyzed again in a different order. For each P(detQmax) and accompanying Q(max) the AG-number was calculated. With these AG numbers, the intra-investigator SD, the inter-investigator SD and the intra- and inter-investigator SD combined were calculated. The intra- and inter-investigator SD combined was 10.7. This implies that if one investigator analyzes a PFS once and determines an AG number of 40, another investigator may determine an AG number between 40 +/- 2. 77*10.7 = 10-70, using a 95% confidence interval. The inter-investigator SD was 10.0 and the intra-investigator SD was 3.7. The reproducibility of the manual analysis of urodynamic studies is moderate owing to a considerable intra- and inter- investigator variation. This is mostly caused by the substantial intra-investigator variation.

Prostate cancer staging: should MR imaging be used?--A decision analytic approach

PURPOSE

To determine the appropriate use of magnetic resonance (MR) imaging for preoperative staging of prostate cancer.

MATERIALS AND METHODS

Literature review was performed by using the principles of evidence-based medicine and medical technology assessment. A decision analytic model was used to compare (a) the strategy that radical prostatectomy is performed on the basis of clinical staging with (b) the strategy that extracapsular disease detected at MR imaging contraindicates radical prostatectomy in patients who were considered surgical candidates on the basis of clinical staging.

RESULTS

After review of the literature, expert panel opinion did not recommend MR staging. No studies in which therapeutic efficacy was addressed were found. The decision analytic model indicated that the strategy including MR staging decreased costs (MR imaging, $10,568; radical prostatectomy, $11,669) and resulted in almost equal life expectancy (MR imaging, 12.59 years; radical prostatectomy, 12.60 years) and quality-adjusted life-years ([QALYs] MR imaging, 12.53; radical prostatectomy, 12.52). Results of sensitivity analyses demonstrated that the MR strategy was both more effective and less costly if the prior probability of extracapsular disease was at least 39% when considering QALY and 50% when considering unadjusted life expectancy.

CONCLUSION

It is not yet conclusively determined whether preoperative MR staging is appropriate, but results of decision analysis suggest that MR staging is cost-effective for men with moderate or high prior probability of extracapsular disease.

The application of three-dimensional contrast-enhanced ultrasound to measure volume of affected tissue after HIFU treatment for localized prostate cancer

INTRODUCTION

Adequate monitoring of volume and location of affected tissue might provide helpful information when performing localized ablative therapy for prostate cancer. We hypothesize that the change in blood flow patterns after therapy in comparison to the blood flow pattern prior to therapy can be used to locate and quantify the amount of affected tissue due to the therapy. We describe the use of three-dimensional contrast-enhanced power Doppler ultrasound (3D-CE-PDU) to determine its additive value to visualize the extent of tissue defects created by high-intensity focused ultrasound (HIFU) in correlation with the histopathology of the prostatectomy specimen.

MATERIALS AND METHODS

Nine patients with biopsy-proven localized prostate cancer, who gave informed consent, were included in the protocol. HIFU treatment was performed 1 week in advance of radical retropubic prostatectomy (RRP) as part of a protocol to study the value of HIFU treatment as local ablative therapy for clinical T(1-2)N(0)M(0) prostate carcinoma. 3D-CE-PDU was performed 1 day prior to unilateral HIFU treatment of the affected lobe on biopsy indication and 1 day before RRP using 2.5 g Levovist((R)) (Schering AG, Germany) microbubble ultrasound contrast agent and a Kretz((R)) Voluson 530D ultrasound scanner (Kretztechnik AG, Austria). Ultrasound data and pathology whole-mount sections were stored digitally to allow off-line processing. Human interpretations of HIFU measurements in three-dimensional ultrasound data were based on gray-scale information (local increase in gray level) in combination with power Doppler mode (absence of blood flow). Histopathological analysis of the whole-mount section revealed a broad band of hemorrhagic necrosis in the HIFU-treated area. Using both the ultrasound data and the pathology sections, the total volume of the prostate and of the HIFU-treated area was measured, and relative volumes were obtained.

RESULTS

Visual inspection of the three-dimensional reconstruction of contrast-enhanced Doppler measurements revealed the HIFU-affected prostate tissue by the absence of a blood flow pattern. Paired t tests of the relative HIFU volume indicated that Doppler results (mean 21.7%, SD +/-10.8%) differed from the pathology results (mean 32.6%, SD +/-16.0%), but a good correlation was found between the relative pathology HIFU volume (Pearson correlation r = 0.94, p<0.0015) and mean 3D-CE-PDU HIFU. Closer inspection of the pathology specimen revealed that the outer ring of the macroscopic hemorrhagic necrosis overestimated the actually dead tissue. On microscopy, the border of dead tissue appeared to be 1-2 mm inside the macroscopically identified red hemorrhagic band. 3D-CE-PDU HIFU volumes indicated by the single observers were not statistically different and correlated very well (Pearson correlation r = 0.98, p<0.001).

CONCLUSION

The results illustrate that 3D-CE-PDU is a promising method to determine the size of the defect of HIFU ablative therapy for prostate carcinoma. The absence of blood flow indicated by three-dimensional power Doppler ultrasound images reflects affected tissue after HIFU treatment, and volume measurements of these areas can quantify the amount of affected tissue.

Polymorphisms in the vitamin D receptor gene and the androgen receptor gene and the risk of benign prostatic hyperplasia

OBJECTIVE

Little is known about risk factors for the development of benign prostatic hyperplasia (BPH). Recently, associations were observed between prostate cancer (CaP) risk and polymorphisms in the vitamin D receptor (VDR) gene and the androgen receptor (AR) gene. Since both receptors are relevant for prostate growth, the VDR and AR are also expected to be involved in the development of BPH. The objective of this study is to establish the relationship between the risk of BPH and a polymorphism in the number of CAG repeats in the AR gene and a TaqI restriction enzyme polymorphism in the VDR gene.

METHODS

For this study, 98 patients who had been treated for BPH-related complaints and 61 convenience controls (predominantly bladder cancer patients) were recruited from the outpatient clinic. DNA was isolated from peripheral blood, and genotyping was performed with PCR-based methods. Means as well as odds ratios (ORs) with 95% confidence intervals (CI) were calculated using SPSS software.

RESULTS

The mean number of CAG repeats in the AR gene in patients and controls was found to be similar: 21.8 (SD = 2.8) and 21.9 (SD = 2.9), respectively. In the subgroup of patients with a prostate volume of at least 50 cm(3), the mean number of repeats was 21.5 (SD = 2.6). The OR for BPH for individuals with homozygous presence of the VDR TaqI restriction fragment length polymorphism (RFLP) (tt) versus individuals with homozygous absence (TT) or heterozygotes (Tt) was found to be 1.0 (95% CI 0.4-2.4). For individuals with a prostate volume of at least 50 cm(3), the OR was 1.2 (95% CI 0.5-3. 2).

CONCLUSION

Unlike earlier observations in prostate cancer, we did not find an association between the CAG repeat polymorphism in the AR gene and the TaqI RFLP polymorphism in the VDR gene and the risk of BPH.

Urodynamic and clinical effects of terazosin therapy in patients with symptomatic benign prostatic hyperplasia

PURPOSE

We evaluated the urodynamic and clinical effects of terazosin in patients with symptomatic benign prostatic hyperplasia (BPH).

MATERIALS AND METHODS

A total of 45 patients who participated in a multicenter trial was evaluated with urodynamic pressure-flow studies before and after 26 weeks of treatment.

RESULTS

Maximum flow rate and symptom score improved significantly in 22 patients with and 11 without bladder outlet obstruction who completed 26 weeks of treatment. In patients with bladder outlet obstruction the condition was significantly reduced and in patients without obstruction, significant urodynamic changes could not be detected.

CONCLUSIONS

Terazosin treatment results in symptomatic relief and improved urinary flow in patients with and without bladder outlet obstruction, and in significant improvement in patients with urodynamically proved obstruction.