ALPHA BLOCKADE FOR THE TREATMENT OF BENIGN PROSTATIC HYPERPLASIA

Is Tamsulosin 0.2 mg Effective and Safe as a First-Line Treatment Compared with Other Alpha Blockers?: A Meta-Analysis and a Moderator Focused Study

PURPOSE

Tamsulosin 0.2 mg is used widely in Asian people, but the low dose has been studied less than tamsulosin 0.4 mg or other alpha blockers of standard dose. This study investigated the efficacy and safety of tamsulosin 0.2 mg by a meta-analysis and meta-regression.

MATERIALS AND METHODS

We conducted a meta-analysis of efficacy of tamsulosin 0.2 mg using International Prostate Symptom Score (IPSS), maximal urinary flow rate (Qmax), post-voided residual volume (PVR), and quality of life (QoL). Safety was analyzed using adverse events. Relevant studies were searched using MEDLINE, EMBASE, and Cochrane library from January 1980 to June 2013.

RESULTS

Ten studies were included with a total sample size of 1418 subjects [722 tamsulosin 0.2 mg group and 696 other alpha-blockers (terazosin, doxazosin, naftopidil, silodosin) group]. Study duration ranged from 4 to 24 weeks. The pooled overall standardized mean differences (SMD) in the mean change of IPSS from baseline for the tamsulosin group versus the control group was 0.02 [95% confidence interval (CI); -0.20, 0.25]. The pooled overall SMD in the mean change of QoL from baseline for the tamsulosin group versus the control group was 0.16 (95% CI; -0.16, 0.48). The regression analysis with the continuous variables (number of patients, study duration) revealed no significance in all outcomes as IPSS, QoL, and Qmax.

CONCLUSION

This study clarifies that tamsulosin 0.2 mg has similar efficacy and fewer adverse events compared with other alpha-blockers as an initial treatment strategy for men with lower urinary tract symptoms.

Establishment of Reference Ranges for Prostate Volume and Annual Prostate Volume Change Rate in Korean Adult Men: Analyses of a Nationwide Screening Population

We aimed to determine normal reference ranges for prostate volume (PV) and annual PV change rate in a Korean nationwide screening population. Data from men who underwent a routine health check-up were collected from 13 university hospitals. The cohort comprised men aged ≥40 yr who had undergone 2 or more serial transrectal ultrasonographies. Men with initial PV>100 mL; serum PSA level>10 ng/mL; PV reduction>20% compared with initial PV, or who had history of prostate cancer or prostate surgery, were excluded. Linear regression and mixed effects regression analyses were used to predict mean PV and longitudinal change in PV over time. A total of 2,967 men formed the study cohort. Age, body mass index (BMI), and serum prostate-specific antigen (PSA) level were found to be significant predictors of PV. A predicted PV table, with a 95% confidence interval (CIs), was developed after adjusting for these 3 variables. Annual PV change rate was 0.51 mL/year (95% CI, 0.47-0.55). Annual PV change rate according to age was 0.68 mL/year, 0.84 mL/year, 1.09 mL/year, and 0.50 mL/year for subjects in their 40s, 50s, 60s, and ≥70 yr, respectively. Predicted annual PV change rate differed depending on age, BMI, serum PSA level and baseline PV. From a nationwide screening database, we established age-, PSA-, and BMI-specific reference ranges for PV and annual PV change rate in Korean men. Our newly established reference ranges for PV and annual PV change rate will be valuable in interpreting PV data in Korean men.

Treatment satisfaction with low-dose tamsulosin for symptomatic benign prostatic hyperplasia: results from a multicentre cross-sectional survey

AIMS

To evaluate the efficacy and treatment satisfaction with low-dose (0.2 mg) tamsulosin in patients with symptomatic benign prostatic hyperplasia (BPH), and to investigate individual lower urinary tract symptoms according to treatment satisfaction.

METHODS

A cross-sectional study was conducted in a total sample of 2574 patients from multiple centres. International Prostate Symptom Score (IPSS), prostate volume, uroflowmetry and combined medications were reviewed. Detailed questionnaires were used to assess treatment satisfaction and IPSS 8 weeks after treatment with low-dose tamsulosin.

RESULTS

After 8 weeks of treatment with low-dose tamsulosin, IPSS improved significantly. Among the 2574 patients, 1,630 (63.42%) were satisfied and 940 patients (36.50%) were dissatisfied with low-dose tamsulosin. The reasons for dissatisfaction included efficacy problems (84.66%) and side effects (3.72%). Treatment satisfaction was affected by symptom duration, baseline IPSS, and prostate size (p = 0.0441, < 0.001, < 0.009, respectively). IPSS voiding (IPSS-V) and IPSS storage (IPSS-S) after treatment differed significantly depending on the degree of satisfaction (p < 0.001). IPSS-V after treatment did not improve in patients who were 'not satisfied' or 'totally not satisfied' (p = 0.170, 0.240, respectively). All the individual IPSS items except urgency (p = 0.1436) varied significantly with the degree of satisfaction (p < 0.001).

CONCLUSIONS

Treating symptomatic BPH with low-dose tamsulosin improved IPSS, but more than one-third of patients were dissatisfied with the treatment. The main reason for dissatisfaction was efficacy problems, and the degree of satisfaction was related to symptom duration, baseline IPSS, and prostate size, and also to IPSS-V. In patients with severe LUTS, the tamsulosin dose should be increased earlier.

Efficacy and Tolerability of Tamsulosin 0.4 mg in Patients with Symptomatic Benign Prostatic Hyperplasia

Purpose

To evaluate the efficacy and tolerability of tamsulosin 0.4 mg once daily in Korean patients with symptomatic benign prostatic hyperplasia (BPH) and investigate whether tamsulosin 0.4 mg can improve symptoms in patients with refractory lower urinary tract symptoms (LUTS) who were previously receiving tamsulosin 0.2 mg once daily.

Materials and Methods

A total of 116 patients from 3 urology centers participated. All study subjects entered a nonblind phase consisting of 8 weeks of tamsulosin 0.2 mg monotherapy followed by an additional 8 weeks of tamsulosin 0.2 mg (0.2 mg group) or 8 weeks of tamsulosin 0.4 mg (0.4 mg group). At week 8, we chose the 0.4 mg group on the basis of International Prostate Symptom Score (IPSS), quality of life (QoL), maximal urinary flow rate (Qmax), and adverse effects. At week 16, we compared the efficacy and tolerability of tamsulosin between the 0.2 and 0.4 mg groups.

Results

A total of 26 patients (22.4%) were escalated to tamsulosin 0.4 mg at week 8. There were significant differences in IPSS, QoL, and Qmax at week 8 in both groups. There were significant differences in improvement in IPSS, QoL, Qmax, and postvoid residual urine volume from baseline to week 16 in both groups. There were no significant differences in efficacy or tolerability between the groups at week 16.

Conclusions

Our trial demonstrated that tamsulosin 0.4 mg has favorable efficacy and tolerability in Korean patients with symptomatic BPH refractory to tamsulosin 0.2 mg. No patients experienced any serious adverse effects when we escalated the dose of tamsulosin to 0.4 mg.

Physiologic reactivity to a laboratory stress task among men with benign prostatic hyperplasia

OBJECTIVES

The sympathetic nervous system and hypothalamic-pituitary-gonadal axis are involved in the pathophysiology of benign prostatic hyperplasia (BPH). The sympathetic nervous system and hypothalamic-pituitary-gonadal axis are also highly reactive to psychological stressors, yet associations between prostate function and reactivity to a psychological stressor have not been examined using standardized psychological stress paradigms. The objective of this study was to examine the associations between psychological stress reactivity and BPH disease parameters.

METHODS

A total of 83 men diagnosed with BPH completed a standardized laboratory stress task, yielding measures of blood pressure, testosterone, and cortisol reactivity. Links were examined between stress reactivity (as indicated by changes in blood pressure, testosterone, and cortisol during the stress task) and measures of BPH disease, including prostate volume, postvoid residual bladder volume, urine flow rate, self-reported lower urinary tract symptoms, and impact and bother scores.

RESULTS

In equations controlling for BPH medications, body mass index, and age, greater diastolic blood pressure reactivity was associated with a greater transition zone volume (P <0.001), greater total prostate gland volume (P <0.05), greater postvoid residual bladder volume (P <0.05), more severe lower urinary tract symptoms (P <0.001), and greater impact scores (P <0.05). Greater cortisol reactivity was associated with greater bother (P <0.05) and impact (P <0.001) scores.

CONCLUSIONS

Physiologic reactivity to a standardized laboratory stressor is associated with objective and subjective BPH disease parameters. These findings contribute to growing data suggesting that stress conditions could be associated with the development or aggravation of prostatic disease.

How can we best characterize the relationship between erectile dysfunction and benign prostatic hyperplasia?

INTRODUCTION

Considerable epidemiological literature exists, showing a relationship between voiding dysfunction and sexual dysfunction. However, few basic science or prospective data are available to determine the nature of the relationship between benign prostatic hyperplasia (BPH)/lower urinary tract symptoms (LUTS) and sexual dysfunction.

METHODS AND DISCUSSION

A critical evaluation of the nature of the relationship between LUTS and erectile dysfunction (ED) must include a look at the nature of the data establishing the relationship, precise definitions of the disease states being evaluated, and adherence to established normative relationships. Criteria for causality will be utilized to best determine the relationship between LUTS and ED. This article will attempt to take a critical and provocative look at where we are presently in establishing a relationship between voiding dysfunction and sexual dysfunction in order to better direct research efforts through evidence-based studies.

CONCLUSION

At present, the epidemiological data do not support a causal relationship based on Hill's criteria for causality between LUTS and ED but suggest a less rigorous association. Additional research is needed to better characterize this relationship.

Stress, hostility, and disease parameters of benign prostatic hyperplasia

OBJECTIVE

Psychological factors such as stress are known to influence activity in the sympathetic nervous system and hypothalamic-pituitary-gonadal axis, systems that in turn have been implicated in the development of benign prostatic hyperplasia (BPH). Associations between psychological stress and prostate function have not been directly examined. The objective of this study was to examine associations among stress, hostility, and BPH disease parameters.

METHODS

Eighty-three men diagnosed with BPH completed self-report and interview measures of stress and hostility followed by measures of urologic function.

RESULTS

Higher lifetime stress was associated with lower prostate volumes and residual urine volumes (p's < .05). By contrast, high recent stress and hostility were associated with greater residual urine (p's < .05). Stress and hostility were not associated with self-report ratings of urologic symptoms.

CONCLUSIONS

Stress and hostility were associated with objective measures of urologic functioning among men with BPH. Results highlight the need for increased attention in research and clinical settings toward associations between psychological factors and urologic disease.

Transurethral needle ablation versus transurethral resection of the prostate for the treatment of symptomatic benign prostatic hyperplasia: 5-year results of a prospective, randomized, multicenter clinical trial

PURPOSE

We report the 5-year efficacy and safety of transurethral needle ablation of the prostate (TUNA) compared to transurethral resection of the prostate (TURP) for the treatment of lower urinary tract symptoms (LUTS) secondary to benign prostatic hyperplasia (BPH).

MATERIALS AND METHODS

A total of 121 men 50 years or older with LUTS secondary to BPH a minimum of 3 months in duration were enrolled in this prospective, randomized clinical trial at 7 medical centers across the United States. Of the participants 65 (54%) were randomly selected to receive TUNA and 56 (46%) were selected to receive TURP. International Prostate Symptom Score, quality of life, peak urinary flow rate, post-void residual urinary volume, and prostate size and configuration were evaluated before the procedure and then annually for 5 years after the procedure. Adverse events were also recorded throughout the study.

RESULTS

Improvement from baseline for TUNA and TURP retained statistical significance at each interval for International Prostate Symptom Score, quality of life and peak flow rate. Post-void residual volume was statistically significant at all time points for TURP and at year 5 for TUNA. The TURP group reported 41% retrograde ejaculation, while the TUNA group reported none. The incident of erectile dysfunction, incontinence and stricture formation was also greater in TURP than in TUNA cases with significantly fewer adverse events for TUNA than for TURP.

CONCLUSIONS

The results of this study demonstrate stable treatment outcomes after 5 years of followup and suggest that TUNA is an attractive treatment option for men with LUTS due to BPH.

A randomized, double-blind crossover study of tamsulosin and controlled-release doxazosin in patients with benign prostatic hyperplasia

OBJECTIVE

To compare the effects of the doxazosin gastrointestinal therapeutic system, extended-release (doxazosin-GITS) formulation, and tamsulosin, another alpha1-antagonist, on total International Prostate Symptom Score (IPSS) and maximum urinary flow rate (Qmax) in treating patients with benign prostatic hyperplasia (BPH).

PATIENTS AND METHODS

Data were analysed from a prospective, randomized, double-blind, crossover study of men aged 50-80 years with concomitant BPH and hypertension as inclusion criteria. Fifty-two men were treated in four phases: phase I, placebo run-in for 2 weeks; phase II, first study drug doxazosin-GITS or tamsulosin for 8 weeks; phase III, washout with placebo for 2 weeks; and phase IV, second study drug tamsulosin or doxazosin-GITS for 8 weeks. Doxazosin-GITS was started at 4 mg/day and tamsulosin at 0.4 mg/day, and then titrated to 8 mg/day and 0.8 mg/day, respectively, after 4 weeks of therapy if the increase in Qmax was < 3 mL/s or the reduction in total IPSS was < 30%. Efficacy assessments included the IPSS and Qmax. Changes in blood pressure were not analysed, as most patients were actually not hypertensive. Endpoint efficacy data were analysed using an analysis of covariance model, with terms for sequence, phase, patients and sequence within patients, in addition to the baseline as covariate. Forty-seven men were treated in both efficacy arms of the study and were evaluable for analysis.

RESULTS

Doxazosin-GITS and tamsulosin significantly relieved lower urinary tract symptoms and significantly increased Qmax from baseline (P = 0.001). Doxazosin-GITS produced significantly greater improvements than tamsulosin in total IPSS (P = 0.019) and obstructive subscores (P = 0.004) at the last treatment visit. The difference between doxazosin-GITS and tamsulosin in improving Qmax approached significance in favour of the former (mean change from baseline 2.6 vs 1.7 mL/s, respectively; between-group difference P = 0.089). Both treatments were well tolerated.

CONCLUSIONS

Treatment with doxazosin-GITS was significantly more effective than tamsulosin in relieving lower urinary tract symptoms.

Are all alpha-blockers created equal? An update

alpha-Receptor blockers, used to treat lower urinary tract symptoms, exert effects on areas of the body other than the prostate where alpha-receptors are located, including the blood vessels and the central nervous system. alpha-Receptors in the central and peripheral nervous system may be involved in bladder activation. alpha(1a)-Receptors are the appropriate target in men with obstructive symptoms, although alpha(1d)-receptors may also be important in patients with irritative symptoms. There is conflicting evidence about the selectivity of alpha-blockers. Clinical trials of these agents do not necessarily reflect results observed in animal and laboratory studies on uroselectivity. The few published comparator studies of alpha-blockers indicate similar efficacies, although side-effect profiles differ somewhat. Randomized, controlled studies of different alpha-blockers with sufficient power to detect differences in side effects between agents are needed.

Meta-analysis of randomized trials of terazosin in the treatment of benign prostatic hyperplasia

OBJECTIVES

To determine the effectiveness of the long-acting alpha(1)-adrenergic receptor blocking agent terazosin compared with placebo on lower urinary tract symptoms and peak urinary flow rate in men with clinical benign prostatic hyperplasia.

METHODS

A formal meta-analysis of all nine randomized trials of terazosin using both an Empirical Bayes and a fully Bayesian approach was conducted. A pooled analysis was conducted on those studies in which patients had a baseline assessment of prostate volume by transrectal ultrasonography.

RESULTS

No evidence of heterogeneity was found in the estimated effects of terazosin on the change in peak flow rates in the studies. Terazosin treatment was associated with an increase in the peak flow rate of 1.4 mL/s (95% confidence interval [1.0, 1.7]) compared with placebo. Terazosin resulted in an average reduction of 2.2 points over placebo (95% confidence interval [1.6, 3.0]) regarding the common symptom score (range 0 to 36 points). A mild heterogeneity was found across the studies, with the decrease in symptom score slightly greater with longer treatment duration. No evidence was found that the baseline prostate volume influenced the effect of terazosin.

CONCLUSIONS

Terazosin was effective and superior to placebo in reducing symptoms and increasing the peak urinary flow rate. The effect of terazosin on the peak urinary flow rate was apparent in studies as short as 8 weeks. Most importantly, the effect of terazosin on symptoms and peak urinary flow rate was independent of the baseline prostate size for the range of prostate volumes reported.

Alpha-blockers: an effective treatment for prostatitis?

Chronic prostatitis is a multifaceted problem affecting men that is both poorly understood and poorly treated. It is inevitable, therefore, that no single treatment will benefit all patients. However, data suggest that some patients' problems can be treated effectively with alpha-blockers. The prostate is rich in alpha-adrenergic receptors, and some urodynamic studies have shown a failure of the bladder neck to relax during voiding. Other studies have demonstrated turbulent flow in the prostate leading to prostatic duct reflux. Because urine is acidic, reflux into the prostatic ducts will cause inflammation and pain. Thus alpha-blockers are an effective treatment for men with prostatitis caused by dysfunctional voiding.

Use of a prostate model to assist in training for digital rectal examination

OBJECTIVES

To assess the accuracy of prostate size estimation on digital rectal examination (DRE) before and after training with a three-dimensional prostate model relative to prostate volume by transrectal ultrasound (TRUS).

METHODS

A total of 100 subjects underwent DRE by one of four family physicians (FP1, n = 34; FP2, n = 26; FP3, n = 22; and FP4, n = 18). One half were examined before any training on DRE prostate size examination and one half after the physicians were trained. Training involved teaching with a three-dimensional prostate model having posterior surface areas corresponding to the average dimensions of six different prostate volumes. The FPs were instructed to estimate the prostate size on the DRE to the nearest 5 g. A single urologist unaware of the DRE results performed TRUS on all patients to measure the prostate volume.

RESULTS

Before training, the DRE size estimates ranged from 10 to 100 g (mean +/- SD 32.8 +/- 21.6), with a TRUS volume of 11 to 122 g (mean +/- SD 38.9 +/- 23.1). The correlation between the DRE and TRUS estimates was 0.25, suggesting low agreement (intraclass correlation coefficient [ICC] 0.35, 95% confidence interval 0.31, 0. 38). After training, 50 different patients had DRE size estimates of 10 to 100 g (mean +/- SD 39.4 +/- 19.7) and TRUS volume of 10 to 119 g (mean +/- SD 41.5 +/- 24.1). The correlation between the techniques was higher in patients examined after training (r = 0. 765), suggesting much better agreement between the techniques (ICC 0. 87; 95% confidence interval 0.86, 0.88). Among the physicians, agreement between DRE and TRUS was higher after training (ICC 0.64 to 0.96) than before training (ICC 0.02 to 0.49).

CONCLUSIONS

Although the subjects examined before and after training differed, the agreement between TRUS and DRE prostate size estimates by the FPs appeared to be stronger after training with a three-dimensional prostate model. This model may be a useful tool to assist in training FPs and medical students to measure prostate size on DRE.

Asymptomatic inflammation and/or infection in benign prostatic hyperplasia

OBJECTIVE

To determine the extent, pattern and clinical significance of asymptomatic histological inflammation and latent infection (National Institute of Health Category IV prostatitis) in benign prostatic hyperplasia (BPH).

PATIENTS AND METHODS

The study included 80 patients (from a cohort of 100 consecutive potentially eligible subjects) with a diagnosis of BPH, but no history or symptoms of prostatitis. Histological sections were obtained from specimens collected prospectively at transurethral resection of the prostate (TURP), immunostained for leukocyte common antigen and scanned using a computerized image-analysis system. Foci of inflammation were categorized as glandular, periglandular, stromal or peri-urethral, and the inflammatory cell density graded from 1 to 3. Relationships and correlations were calculated between the volume, degree and type of inflammation, presence and type of bacteria (culture of deep prostatic biopsies), the use of catheters and prostate specific antigen (PSA) levels.

RESULTS

Inflammation was identified in all patients but the mean tissue surface area involved was only 1.1% of the total specimen, with periglandular inflammation being the predominant pattern (0.5%). Of the prostate specimens, 44% showed bacterial growth (in 67% of the catheterized patients and 28% of those uncatheterized; 42% of patients were catheterized before TURP). There was no significant difference between any combination of inflammation pattern, volume or grade of inflammation in those catheterized or not (P=0.15) or culture-positive (pathogenic or not) and culture-negative cases (P=0.06). Neither total PSA or PSA density was significantly correlated (P>0.05) with the amount, degree or distribution of inflammation.

CONCLUSION

Prostatic inflammation is an extremely common histological finding in patients with symptoms of BPH who have no symptoms of prostatitis. There was no correlation between the degree and pattern of inflammation, catheterization, presence of bacteria, serum PSA or PSA density. The clinical significance of asymptomatic Category IV chronic prostatitis associated with BPH has yet to be determined.

Heritability of the symptoms of benign prostatic hyperplasia and the roles of age and zonal prostate volumes in twins

OBJECTIVES

Both benign prostatic hyperplasia and lower urinary tract symptoms (LUTS) have been shown to increase with age in men, but a causal relationship between prostate volume and symptoms has not been established. This study had two aims, to investigate the inter-relationships of age, symptoms, and various zonal measurements in the prostate and to assess the impact of heritable influences on symptom score.

METHODS

Eighty-three monozygotic twin pairs and 83 dizygotic twin pairs were studied to determine age and LUTS as assessed by the American Urological Association symptom score. Their prostate volumes (total, transition zone, and peripheral zone) were measured by transrectal ultrasound.

RESULTS

There was significant evidence of pairwise correlation between transition zone and symptom score (P = 0.04) and between age and symptom score (P = 0.03). Age also showed significant correlation with all volume measurements. Heritability appears to account for 82.6% of the variability in symptom score in men older than 50 years.

CONCLUSIONS

This study provides evidence that age and transition zone volume play a role in LUTS, but also that their influence is not strong. Estimates of heritability suggest that hereditary factors contribute substantially to LUTS.

Sexual dysfunction in patients with benign prostatic hyperplasia

Two of the most common problems presenting to urologists are benign prostatic hyperplasia and sexual dysfunction, with an increasing number of patients presenting for treatment as a result of the proliferation of less invasive therapies. How such therapies for lower urinary tract symptoms affect sexual function in men is important to both urologists and their patients, and is the focus of this review.

The medical management of lower urinary tract symptoms and benign prostatic hyperplasia

Prostatism is a widely used term assigned to the symptom complex of older men with voiding dysfunction. The cause of the syndrome has routinely been ascribed to an enlarged prostate. More recent thinking recognizes that many men with such symptoms do not, in fact, have prostate enlargement or benign prostatic hyperplasia (BPH) and that such symptoms are not a surrogate for BPH. Such recognition is essential if cost effective medical management of lower urinary tract symptoms (LUTS) is to be achieved. Prostate volume has emerged as a key factor in the selection of medical therapy of LUTS and BPH not only regarding symptom relief but also to the newer concept of the prevention of disease progression and the avoidance of future adverse events in those men with true BPH. In the United States, medical management is now first line therapy for LUTS. The proper selection of therapy based on the patient's individual pathophysiologic characteristics is now made possible by many new recent studies within the medical literature.

Phase III multicenter placebo-controlled study of tamsulosin in benign prostatic hyperplasia. Tamsulosin Investigator Group

OBJECTIVES

To evaluate the efficacy and safety of two once-daily doses of tamsulosin, the first selective alpha1A-antagonist studied in clinical trials.

METHODS

Patients with benign prostatic hyperplasia (BPH) were randomized to receive either tamsulosin (0.4 and 0.8 mg/day) or placebo (n = 756). Primary efficacy parameters were improvement in the total American Urological Association (AUA) symptom score and peak urinary flow (Qmax). Secondary efficacy parameters were improvement in measurements at individual double-blind visits corresponding to the primary efficacy parameters; percentage of patients with a 3-mL/s increase in Qmax; total AUA irritative, obstructive, and bother scores; individual AUA symptom scores; total, irritative, obstructive, and individual Boyarsky symptom scores; average urinary flow rate and other uroflowmetric parameters; and investigator's global assessment.

RESULTS

Statistically significant improvements in all efficacy parameters were observed in tamsulosin-treated compared with placebo-treated patients. Additionally, the 0.4-mg/day dose demonstrated a rapid onset of action (4 to 8 hours) based on Qmax after the first dose of double-blind medication. A review of the safety parameters demonstrated excellent tolerance at 1 week after the initial 0.4-mg/day dose and continued tolerance during the additional 12 weeks of 0.4- and 0.8-mg/day dosing. The incidence of positive orthostatic test results in the tamsulosin groups was comparable to that observed in the placebo group. Adverse events were comparable in the 0.4-mg/day tamsulosin and placebo groups and were somewhat higher in the 0.8-mg/day tamsulosin group.

CONCLUSIONS

Tamsulosin was effective, safe, and well tolerated in the target BPH population at both the 0.4- and 0.8-mg/day dose levels, without the blood pressure-lowering effects typical of nonselective alpha-adrenergic antagonists.

Evaluation of the effect of endothelin-1 and characterization of the selective endothelin a receptor antagonist PD155080 in the prostate

PURPOSE

To evaluate the contractile effect of endothelin-1 (ET-1) on prostatic urethral pressure and to characterize the effect of the selective ETA receptor antagonist PD155080 on ET-1 mediated prostatic urethral pressure.

MATERIALS AND METHODS

The effect of intravenous ET-1 administration on canine urethral pressure was determined in the presence and absence of PD155080. The affinity of PD155080 for endothelin-mediated contraction was determined using antagonist dissociation studies. Saturation and competition binding studies were performed using [125I] ET-1 in both human and canine prostate.

RESULTS

ET-1 bolus injection elicited shallow and prolonged increases the prostatic urethral pressure. Pretreatment with PD155080 totally abolished the urethral contractile response to ET-1. Specific [125I] ET-1 binding was saturable and of high affinity. Two ET receptor subtypes (ETA receptor, ETB receptor) have been identified in human prostate. The ratio of ETA to ETB receptors was approximately 1.5:1 in both human and canine prostates. Isometric tension studies revealed that PD155080 shifted the ET-1 dose-response curves to the right and exhibited no effect on the ETB receptor selective agonist sarafotoxin dose-response curves.

CONCLUSION

ET-1 mediates prostate smooth muscle tone and may play a role in the pathophysiology and treatment of benign prostatic hyperplasia (BPH).

Incidence and clinical significance of high-grade prostatic intraepithelial neoplasia in TURP specimens

OBJECTIVES

To determine the incidence and clinical significance of high-grade prostatic intraepithelial neoplasia (PIN) in specimens obtained from transurethral resection of the prostate (TURP).

METHODS

All TURP specimens accessioned to the general surgical pathology service of the Johns Hopkins Hospital (JHH) from March 1984 through December 1987 that did not contain adenocarcinoma of the prostate were reviewed for the presence of high-grade PIN (PIN 2 and PIN 3). These cases were supplemented with cases from the consultation files of the JHH, the Armed Forces Institute of Pathology, and the University of Michigan Hospitals. In total, 85 cases of high-grade PIN in TURP specimens were identified.

RESULTS

The mean age of the patients at the time of TURP was 70 years and the median age was 71 years (range 50 to 89). Sixty-three patients (74%) were 65 years of age or older, 45 patients (53%) were at least 70 years of age, and 14 patients (16%) were 60 years of age or younger. Adenocarcinoma of the prostate was discovered in 9 (22%) of 41 patients with follow-up information. Based on material from JHH, the incidence of high-grade PIN was 2.3% in all TURP specimens and 3.2% in those without invasive carcinoma.

CONCLUSIONS

High-grade PIN on TURP is relatively uncommon and is diagnosed in an elderly population. Patients with high-grade PIN on TURP appear to be at increased risk of developing prostatic carcinoma, although not to the same degree as patients with high-grade PIN on needle biopsy.

Correlation between prostate size estimated by digital rectal examination and measured by transrectal ultrasound

OBJECTIVES

To correlate prostate size estimates performed by single or multiple examiners through digital rectal examination (DRE) with volume measured by transrectal ultrasound (TRUS) and to propose measures for predicting prostate volume using DRE estimates in clinical settings.

METHODS

Data from four sources were analyzed: (1) the Olmsted County community study of 397 patients examined by a single urology nurse, with TRUS measurements done by multiple examiners; (2) a community study in Stirling, Scotland, involving 480 patients with DRE and TRUS performed by one urologist; (3) baseline data from the Veterans Affairs Cooperative Study No. 359 in 1222 patients with DRE and TRUS measurements by multiple personnel at 31 centers; and (4) a clinical series of 100 men with DRE and TRUS by a single urologist.

RESULTS

DRE estimates and TRUS volumes were significantly correlated (r = 0.4 to 0.9), but prostate size was underestimated by 25% to 55% for men with a prostate volume over 40 mL, depending on the study, with greater variability for studies involving multiple examiners. In one study that assessed prostate dimensions by DRE, posterior surface area (SA) correlated with overall TRUS volume (r = 0.4). According to receiver operating characteristic curves, SA showed a 70% and 76% chance of correctly identifying men with prostate volume greater than 30 or 40 mL, respectively; those with larger prostates were best distinguished by SA greater than 7 cm2 (sensitivity greater than 0.74, specificity greater than 0.50).

CONCLUSIONS

DRE underestimates prostate size, particularly if TRUS volume is greater than 30 mL. However, DRE estimates may help identify prostates likely to be larger than certain cutpoints by TRUS. Posterior SA may be useful as a preliminary assessment when prostate size is an important predictor of therapeutic response.

Evaluation of voiding cystourethrography prior to renal transplantation

In many centers, voiding cystourethrography is a routine part of pretransplantation assessment of the lower urinary tract. To assess the value of this investigation, a retrospective review of transplant candidates evaluated in our center over 2 years was undertaken. A total of 517 patients were fully evaluable. Only 13 voiding cystourethrograms (VCUGs) (2.5%) of 517 were found to be abnormal. Three patients with reflux alone did not require intervention before transplantation. Four patients with decreased bladder capacity underwent hydrodistention. Two patients increased their capacity to over 150 ml and two patients failed distention, one requiring an ileal conduit and the other requiring an augmentation cystoplasty. Three patients had increased postvoid residual (PVR). Two patients started clean intermittent catheterization. One required prostate resection for benign prostatic hypertrophy. One patient with reflux and decreased bladder capacity refused treatment. One patient with reflux combined with increased PVR started clean intermittent catheterization and was cleared for transplant surgery. One patient with decreased bladder capacity and increased PVR had a stroke and was excluded from transplantation. All 13 patients with abnormal VCUGs had a prior urologic history. In total, only 56 of 517 patients evaluated had a prior urological history. Each VCUG costs approximately $500. Limiting VCUG studies to those patients with a prior urological history would have resulted in a significant cost savings. Hence, we recommend that only patients with a prior urological history should undergo this costly and often distressing examination.

Phytotherapy in treatment of benign prostatic hyperplasia: a critical review

Phytotherapeutic agents have enjoyed widespread use, especially in Europe, for the treatment of BPH. With the recent proliferation of nutrition and vitamin stores in the United States, use of these agents has greatly increased. Although SPB extract is the most extensively studied of the phytotherapeutic agents used for BPH, no well-defined mechanism of action has been proposed. Evidence for an antiandrogenic or antiestrogenic effect is conflicting, and there are no clinical data suggesting an effect on 5-alpha-reductase activity. Furthermore, clinical trials with SPB have largely been uncontrolled and are thus of limited value in ascertaining the true clinical impact of this agent. Double-blind, controlled studies with SPB also have limitations in that most were of very short duration (none longer than 3 months) and did not provide entry or exclusion criteria. In addition, standardized symptom scores were not utilized. Only two of seven studies showed an appropriate placebo response, and the results and conclusions of both these studies were contradictory. The best and most convincing study of the efficacy of phytotherapeutic agents (using Harzol) was recently published in the Lancet. This study was rigorous and matched in design and format with pharmaceutical industry trials. A mild but appropriate placebo response was detected, which further validates the study. However, a prior placebo-controlled study showed no efficacy of beta-sitosterol-beta-D-glucoside. This dichotomy of results possibly reflects the different composition of the agents tested. This is a major confounding factor in this field of study, especially because the active ingredients are unknown. Standardization of the compounds is needed to compare and assess accurately the effect of the different extracts.