Transition zone ratio and prostate-specific antigen density as predictors of the response of benign prostatic hypertrophy to alpha blocker and anti-androgen therapy

General effect of low-dose tamsulosin (0.2 mg) as a first-line treatment for lower urinary tract symptoms associated with benign prostatic hyperplasia: a systematic review and meta-analysis

PURPOSE

In Asian countries, low-dose tamsulosin (0.2 mg) is used widely but this dose has been less popular than 0.4 mg tamsulosin or other types of alpha blockers. The aim of this study was to investigate the efficacy and safety of low-dose tamsulosin by systematic review and meta-analysis.

METHODS

We conducted a meta-analysis of improvements of lower urinary tract symptoms using International Prostate Symptom Score (IPSS), maximal urinary flow rate (Qmax), post-voided residual volume (PVR), and quality of life (QOL). Relevant studies were found using MEDLINE, Embase, and the Cochrane library. Final inclusion was determined by randomized controlled trials (RCT) and performance of IPSS.

RESULTS

A total of fourteen studies were included, with a total sample size of 2147 subjects (1044 experimental and 1103 controls). Study durations ranged from 4 to 52 weeks. The mean change of IPSS improvement from baseline for tamsulosin was -7.18 (95% CI: -7.83, -6.54). The mean change of QOL improvement from baseline was -1.34 (95% CI: -1.46, -1.22). The overall Qmax improvement from baseline was 2.32 ml/sec (95% CI: 1.95, 2.70). The mean change of PVR improvement from baseline was -11.12 ml (95% CI: -17.61, -4.64). Regarding safety, four studies did not report any adverse events while others reported that adverse events were all tolerated.

CONCLUSIONS

Although this study did not consider placebo effect and has high IPSS baseline scores, this study clarifies that low-dose tamsulosin has generally positive effect and safety in treatment of LUTS and could be a suitable option as an initial treatment, especially for patients with low body mass index, as is typical of Asian people.

WITHDRAWN: Tamsulosin for benign prostatic hyperplasia

BACKGROUND

Benign prostatic hyperplasia (BPH) is a nonmalignant enlargement of the prostate which can result in bothersome lower urinary tract symptoms. The treatment goal for men with BPH is to relieve these bothersome symptoms.

OBJECTIVES

This systematic review assessed the effects of tamsulosin in the treatment of lower urinary tract symptoms (LUTS) compatible with BPH.

SEARCH STRATEGY

Trials were searched in computerized general and specialized databases (MEDLINE, EMBASE, Cochrane Library), by checking bibliographies, and by contacting manufacturers and researchers.

SELECTION CRITERIA

Trials were eligible if they (1) randomized men with BPH to receive tamsulosin in comparison with placebo, other BPH medications or surgical interventions and (2) included clinical outcomes such as urologic symptom scales, symptoms, or urodynamic measurements, and (3) had a treatment duration of 30 days or longer. Eligibility was assessed by at least two independent observers.

DATA COLLECTION AND ANALYSIS

Information on patients, interventions, and outcomes were extracted by at least two independent reviewers using a standard form. The main outcome measure for comparing the effectiveness of tamsulosin with placebo, medical or surgical interventions was the change in urologic symptom scale scores. Secondary outcomes included changes in urinary flow measures (peak urine flow rate). The main outcome measure for adverse effects was the number of men reporting adverse effects.

MAIN RESULTS

Fourteen studies involving 4122 subjects met inclusion criteria. Study duration ranged from 4 to 26 weeks, and no placebo-controlled study lasted longer than 13 weeks. The mean age of subjects was 64 years. Baseline symptom scores and urine flow rates demonstrated that men had moderate LUTS. Tamsulosin improved symptoms and peak urine flow relative to placebo. The weighted mean differences (WMD) for mean change from baseline for the Boyarsky symptom score for 0.4 mg and 0.8 mg doses of tamsulosin relative to placebo were -1.1 points (95% CI = -1.49 to -0.72; 12% improvement) and -1.6 points (95% CI = -2.3 to -1.0; 16% improvement), respectively. The WMD for mean change from baseline in peak urine flow were 1.1 mL/sec (95% CI = 0.59 to 1.51) and 1.1 mL/sec (95% CI= 0.65 to 1.48) for 0.4 mg and 0.8 mg, respectively. Tamsulosin (0.2 mg to 0.4 mg) was as effective as other alpha antagonists and the phytotherapeutic agent Permixon® in improving symptoms and flow rates though the doses of all alpha-antagonists studied may not have been optimal. Discontinuations from treatment for any reason and discontinuations "due to adverse events" were similar in the low dose tamsulosin (0.2 mg) and placebo groups but increased to 16% in trials utilizing a 0.8 mg dose of tamsulosin. Low dose tamsulosin was generally well tolerated although not all the trials reported specific adverse events. The most frequently reported adverse events that were significantly greater than placebo included dizziness, rhinitis and abnormal ejaculation. Adverse effects increased markedly as tamsulosin dosing increased, and were reported in 75% of men receiving the 0.8 mg dose. Men receiving a 0.2 mg dose tamsulosin were less likely to discontinue treatment compared to men receiving terazosin.

AUTHORS' CONCLUSIONS

Tamsulosin provided a small to moderate improvement in urinary symptoms and flow compared to men receiving placebo in men with BPH. Effectiveness was similar to other alpha antagonists and increased only slightly with higher doses. Long term effectiveness and ability to reduce complications due to BPH progression could not be determined. Adverse effects were generally mild but their frequency, including withdrawals, increased substantially with the higher doses that are generally available for treatment.

Effects of dietary flaxseed lignan extract on symptoms of benign prostatic hyperplasia

A flaxseed lignan extract containing 33% secoisolariciresinol diglucoside (SDG) was evaluated for its ability to alleviate lower urinary tract symptoms (LUTS) in 87 subjects with benign prostatic hyperplasia (BPH). A randomized, double-blind, placebo-controlled clinical trial with repeated measurements was conducted over a 4-month period using treatment dosages of 0 (placebo), 300, or 600 mg/day SDG. After 4 months of treatment, 78 of the 87 subjects completed the study. For the 0, 300, and 600 mg/day SDG groups, respectively, the International Prostate Symptom Score (IPSS) decreased -3.67 +/- 1.56, -7.33 +/- 1.18, and -6.88 +/- 1.43 (mean +/- SE, P = .100, < .001, and < .001 compared to baseline), the Quality of Life score (QOL score) improved by -0.71 +/- 0.23, -1.48 +/- 0.24, and -1.75 +/- 0.25 (mean +/- SE, P = .163 and .012 compared to placebo and P = .103, < .001, and < .001 compared to baseline), and the number of subjects whose LUTS grade changed from "moderate/severe" to "mild" increased by three, six, and 10 (P = .188, .032, and .012 compared to baseline). Maximum urinary flows insignificantly increased 0.43 +/- 1.57, 1.86 +/- 1.08, and 2.7 +/- 1.93 mL/second (mean +/- SE, no statistical significance reached), and postvoiding urine volume decreased insignificantly by -29.4 +/- 20.46, -19.2 +/- 16.91, and -55.62 +/- 36.45 mL (mean +/- SE, no statistical significance reached). Plasma concentrations of secoisolariciresinol (SECO), enterodiol (ED), and enterolactone (EL) were significantly raised after the supplementation. The observed decreases in IPSS and QOL score were correlated with the concentrations of plasma total lignans, SECO, ED, and EL. In conclusion, dietary flaxseed lignan extract appreciably improves LUTS in BPH subjects, and the therapeutic efficacy appeared comparable to that of commonly used intervention agents of alpha1A-adrenoceptor blockers and 5alpha-reductase inhibitors.

Local injection of a sustained-release antiandrogen formulation into a target prostatic site: an experimental study

OBJECTIVE

To evaluate the efficacy of one intraprostatic injection with sustained-release chlormadinone acetate (CMA-SR) in rats.

MATERIALS AND METHODS

CMA, a steroidal antiandrogen, was enclosed in microcapsules for sustained-release (CMA-SR). Forty-eight rats were divided into group A (intraprostatic CMA-SR 8 mg/kg, one injection), group B (as A but with 25 mg/kg), group C (intraprostatic, vehicle only) and group D (subcutaneous, s.c., CMA 10 mg/kg once daily for 4 weeks). Prostate weight, body weight and plasma testosterone levels were measured for up to 4 weeks.

RESULTS

After a s.c. injection with CMA-SR, residual CMA at the s.c. injection site decreased with time. The injected prostate lobe weighed significantly (P < 0.05) less than the contralateral lobe in groups A and B, and significantly (P < 0.05) less in groups A and B than in group C. Both prostate lobes in group D were significantly (P < 0.05) smaller than in group C (P < 0.05). Plasma testosterone levels were significantly lower in group D than in group C (P < 0.05).

CONCLUSIONS

The sustained release of CMA after one intraprostatic injection persistently decreased the weight of the target prostate. This new concept of antiandrogen therapy might therefore be effective in man, with fewer systemic adverse reactions.

Resistance index in benign prostatic hyperplasia using power doppler imaging and clinical outcomes after transurethral vaporization of the prostate

BACKGROUND

Using power Doppler ultrasonography (PDUS), we investigate the change of resistance index (RI) before and after transurethral vaporization of the prostate (TUVP) in benign prostatic hyperplasia (BPH) patients.

METHODS

In all, 49 patients underwent transrectal PDUS before receiving TUVP, three were excluded because of cancer and three could not be followed up. The remaining 43 were enrolled in the present study. Patients were assessed before and 1, 3 and 6 months after surgery, giving a mean duration of follow-up of 9.1 months. International prostate symptom scores (IPSS), quality of life (QOL) scores, postvoiding residual urine volumes (PVR) and maximum urinary flow rates (Qmax) were evaluated and total prostatic volume (TPV) and RI were measured using PDUS.

RESULTS

Resistance index ranged from 0.64 to 0.91. The postoperative parameters except for RI, such as TPV, PVR, IPSS and QOL scores improved significantly at the follow-up assessment after surgery. The elevated RI decreased significantly 1, 3 and 6 months after the treatment. Resistance index significantly decreased after TUVP and IPSS and other urodymamics parameters improved.

CONCLUSIONS

The present study suggested that RI could evaluate the severity of BPH and the degree of intraprostatic pressure or bladder outlet obstruction.

Influence of androgen deprivation therapy on volume of anatomic zones of prostate in patients with prostate cancer using magnetic resonance imaging

OBJECTIVES

To clarify the influence of androgen deprivation therapy (ADT) on the volume of the anatomic zones of the prostate and the tissue component of the transition zone.

METHODS

Thirty patients with prostate cancer arising and localizing in the peripheral zone were enrolled in this study. The volume of anatomic zones was measured using magnetic resonance imaging before and 6 months after ADT (castration and flutamide). Binary images were constructed to analyze the tissue components of the transition zone.

RESULTS

The volumes after ADT in the whole prostate, transition zone, and peripheral zone were significantly smaller than the corresponding volumes before ADT (P <0.001). A small correlation was found between the reduction rates of the transition zone after therapy and the stromal rates of the transition zone (r(s) = 0.375, P = 0.041).

CONCLUSIONS

The present results revealed that, not only the epithelial region in the transition zone, but also the stromal region, was sensitive to androgen and the volume of the transition zone was reduced during ADT regardless of its histologic components.

Alpha-blocker test: Alternative to pressure-flow study of bladder outlet obstruction and detrusor contractility in patients without an enlarged prostate

OBJECTIVES

We investigated whether the cause of urinary disturbance in men with a prostate volume < or =20 mL can be determined by analyzing the efficacy of alpha1-adrenoceptor antagonist (alpha-blocker) treatment.

METHODS

Thirty-five men who were >50 years of age, with an International Prostate Symptom Score (IPSS) > or =8 points, a quality of life (QOL) index > or =2 points and a prostate volume </=20 mL were enrolled in the non-enlarged prostate group. Twenty-six men who met the above conditions but who had a prostate volume >20 mL served as controls. The alpha1-adrenoceptor antagonist tamsulosin was administered at a dose of 0.2 mg/day for 4 weeks. Results for the IPSS, QOL index, free flowmetry and pressure-flow studies were obtained before and after tamsulosin administration.

RESULTS

In both groups, tamsulosin improved the IPSS and QOL index and the bladder outlet obstruction index (BOOI) was lowered without reducing the bladder contractility index (BCI). No parameter showed a significant difference in treatment efficacy between the two groups. In the non-enlarged prostate group, both the pretreatment BOOI and BCI correlated with the efficacy of treatment in improving maximum flow rate (Qmax). In the enlarged prostate group, BOOI and BCI did not correlate with Qmax. When Qmax was improved by > or =3.5 mL/s, the positive predictive value for both pretreatment BOOI >40 and BCI >100 was 100% in the non-enlarged prostate group.

CONCLUSIONS

The alpha-blocker test is one method to assess the presence of bladder outlet obstruction and the state of detrusor contractility in men without an enlarged prostate.

Tamsulosin for benign prostatic hyperplasia

BACKGROUND

Benign prostatic hyperplasia (BPH) is a nonmalignant enlargement of the prostate which can result in bothersome lower urinary tract symptoms. The treatment goal for men with BPH is to relieve these bothersome symptoms.

OBJECTIVES

This systematic review assessed the effects of tamsulosin in the treatment of lower urinary tract symptoms (LUTS) compatible with BPH.

SEARCH STRATEGY

Trials were searched in computerized general and specialized databases (MEDLINE, EMBASE, Cochrane Library), by checking bibliographies, and by contacting manufacturers and researchers.

SELECTION CRITERIA

Trials were eligible if they (1) randomized men with BPH to receive tamsulosin in comparison with placebo, other BPH medications or surgical interventions and (2) included clinical outcomes such as urologic symptom scales, symptoms, or urodynamic measurements, and (3) had a treatment duration of 30 days or longer. Eligibility was assessed by at least two independent observers.

DATA COLLECTION AND ANALYSIS

Information on patients, interventions, and outcomes were extracted by at least two independent reviewers using a standard form. The main outcome measure for comparing the effectiveness of tamsulosin with placebo, medical or surgical interventions was the change in urologic symptom scale scores. Secondary outcomes included changes in urinary flow measures (peak urine flow rate). The main outcome measure for adverse effects was the number of men reporting adverse effects.

MAIN RESULTS

Fourteen studies involving 4,122 subjects met inclusion criteria. Study duration ranged from 4-26 weeks, and no placebo-controlled study lasted longer than 13 weeks. The mean age of subjects was 64 years. Baseline symptom scores and urine flow rates demonstrated that men had moderate LUTS. Tamsulosin improved symptoms and peak urine flow relative to placebo. The weighted mean differences (WMD) for mean change from baseline for the Boyarsky symptom score for 0.4 mg and 0.8 mg doses of tamsulosin relative to placebo were -1.1 points (95% CI = -1.49, -0.72; 12% improvement) and -1.6 points (95% CI = -2.3, -1.0; 16% improvement), respectively. The WMD for mean change from baseline in peak urine flow were 1.1 mL/sec (95% CI = 0.59, 1.51) and 1.1 mL/sec (95% CI= 0.65, 1.48) for 0.4 mg and 0.8 mg, respectively. Tamsulosin (0.2 mg-0.4 mg) was as effective as other alpha antagonists and the phytotherapeutic agent Permixon in improving symptoms and flow rates though the doses of all alpha-antagonists studied may not have been optimal. Discontinuations from treatment for any reason and discontinuations "due to adverse events" were similar in the low dose tamsulosin (0.2 mg) and placebo groups but increased to 16% in trials utilizing a 0.8 mg dose of tamsulosin. Low dose tamsulosin was generally well tolerated although not all the trials reported specific adverse events. The most frequently reported adverse events that were significantly greater than placebo included dizziness, rhinitis and abnormal ejaculation. Adverse effects increased markedly as tamsulosin dosing increased, and were reported in 75% of men receiving the 0.8 mg dose. Men receiving a 0.2 mg dose tamsulosin were less likely to discontinue treatment compared to men receiving terazosin.

REVIEWER'S CONCLUSIONS

Tamsulosin provided a small to moderate improvement in urinary symptoms and flow compared to men receiving placebo in men with BPH. Effectiveness was similar to other alpha antagonists and increased only slightly with higher doses. Long term effectiveness and ability to reduce complications due to BPH progression could not be determined. Adverse effects were generally mild but their frequency, including withdrawals, increased substantially with the higher doses that are generally available for treatment.

Evidence-based meta-analysis of pharmacotherapy for benign prostatic hypertrophy

Evidence-based diagnosis and treatment have been proposed recently in various medical fields. Evidence-based diagnostic and therapeutic guidelines for benign prostatic hypertrophy (BPH), one of the most common urological diseases, have been proposed in foreign countries. This paper examines common therapeutic drugs for BPH in Japan from the viewpoint of evidence-based medicine (EBM). The term 'BPH' and drugs indicated for BPH were used as key words to search related articles in the PubMed website. A total of 813 articles extracted as of October 2001 were examined. The articles were ranked in levels ranging from I-V, where Level I indicated a large randomized controlled trial and Level V indicated a non-controlled case accumulation study. Among the 813 articles extracted, 132 clinical articles were suitable for evaluation. There were many reliable articles on the effectiveness of alpha-blockers. However, it seemed necessary to examine further how to choose the optimum alpha-blocker for each clinical case and the combination of antiandrogen drugs with alpha-blockers. It was also considered necessary to evaluate the effectiveness of drugs, such as eviprostat and hachimi-jio-gan, that are available only in Japan. The present study evaluated the effectiveness of commonly available therapeutic drugs for BPH in Japan from a viewpoint of EBM.

The value of power Doppler imaging to predict the histologic components of benign prostatic hyperplasia

BACKGROUND

The response of symptoms caused by benign prostate hypertrophy (BPH) to alpha blockade is related to the area density of the smooth muscle of the prostate. If this density could be determined by ultrasound examination, ultrasound might be useful in predicting the efficacy of alpha-blocker therapy. In this study, various ultrasonographic parameters obtained by transrectal method (TRUS) were compared with histologically measured components.

METHODS

Before surgery, ultrasonic power Doppler imaging (PDI) of the prostate was performed using a transrectal probe. The volume of total prostate, transition zone (TZ), and the presumed circle area ratio (PCAR) [1,2] were calculated. Pulsatile blood flow was recorded, and the resistive index (RI) was calculated. Based on the serum concentration of total prostate specific antigen (PSA), ratio of PSA to prostate volume (PSAD), and ratio of PSA to TZ (PSAT) were calculated. Prostate tissues were obtained from 26 patients undergoing transurethral resection, suprapubic prostatectomy, or radical cystectomy, and were analyzed by quantitative morphometry. Computer image analysis was used to determine the mean area densities of the smooth muscle (SM), connective tissue (CT), glandular epithelium (GE) and lumen (GL), and vascular lumen (V). Correlations between ultrasonographic parameters and morphometric data were studied.

RESULTS

On microscopic examination, the specimens showed a wide variety, ranging from normal prostate to typical glandular hyperplasia. There was a correlation between RI and the ratios of the four components (SM: r = -0.42 P = 0.034; CT: r = -0.42 P = 0.030; GE: r = 0.42 P = 0.032; GL: r = 0.46 P = 0.018). However, correlations between the other five transrectal parameters and the composition of the prostate were not so clear. This may have been because the blood vessels are compressed within the surgical capsule together with the urethra.

CONCLUSIONS

The present study demonstrates that when RI is calculated by PDI, it can be quite useful for predicting component ratios, thereby making it possible to predict the therapeutic efficacy of alpha-blockers in individual patients.

Aspects of imaging in the assessment and follow up of benign prostatic hyperplasia

For assessing patients suffering from benign prostatic hyperplasia and monitoring subsequent treatment, symptom questionnaires, uroflowmetry, prostate volume measurements, postvoiding residual urine volume measurements and pressure-flow studies may be used. This review highlights aspects of imaging in the assessment of benign prostatic hyperplasia, including volume determinations of prostate and postvoiding residual urine, texture imaging and biopsy guidance. Future developments are also briefly discussed.

Transition zone index as a risk factor for acute urinary retention in benign prostatic hyperplasia

OBJECTIVES

To examine the efficacy of various parameters obtained by transrectal ultrasonography (TRUS) as predictors of the onset of acute urinary retention in patients with benign prostatic hyperplasia (BPH).

METHODS

From April 1993 to March 1997, 331 men aged 51 to 84 years with symptoms of BPH were enrolled in this study. Among them, 64 patients presented to our clinic because of acute urinary retention. TRUS was used to calculate the transition zone (TZ) volume, the transition zone index (TZ index = TZ volume/total prostate volume), the total prostate volume, and presumed circle area ratio (PCAR). To compare the usefulness of the various indices, the area under the receiver-operator characteristic (ROC) curve was calculated for each index.

RESULTS

There were significant differences in the American Urological Association (AUA) symptom score, total prostate volume, TZ volume, TZ index, and PCAR between patients with and without acute urinary retention, but no significant differences in age and quality of life score. In patients with acute urinary retention, the area under the ROC curve was 0.924 for the TZ index, 0.834 for the TZ volume, 0.753 for the PCAR, 0.684 for the total prostate volume, and 0.628 for the AUA symptom score.

CONCLUSIONS

The TZ index is an accurate predictor of acute urinary retention in patients with BPH and may be a useful method for deciding between surgical intervention and antiandrogen treatment.

Comprehensive patient evaluation for benign prostatic hyperplasia

It is time to consider new approaches to benign prostatic hyperplasia (BPH). Previously, obstruction, prostatism, and hyperplasia of the prostate were considered to be almost synonymous. Today, there is increasing awareness that some men have hyperplasia, some have symptoms, and others obstruction. Currently, BPH is discussed in terms of benign prostatic enlargement (BPE), bladder outlet obstruction (BOO), and lower urinary tract symptoms (LUTS). Symptom questionnaires, uroflowmetry, prostate volume determination, residual urine volume determination, and pressure-flow studies continue to be the instruments used for assessing BPH patients. Prostate enlargement, prostatic muscle tone, and bladder function all impact voiding function. A large part of BPH symptomatology may be explained by bladder dysfunction, which tends to be discounted in discussions about BPH. In the future, bladder dysfunction must receive more attention, and better measures should be developed to quantify it. Postvoid residual urine is a sign of abnormal bladder function rather than the result of BOO. However, variability limits the predictive value of residual urine volume. Uroflowmetry is also criticized for excessive variability, which is increased among men with LUTS secondary to BPH. Approximately 70% of men with uroflow < 15 mL/sec are obstructed, which means that at least 10 million men in the United States have BOO. Therefore, alleviation of obstruction would be a daunting and overwhelming task. It is still widely believed that prostatism is due to an enlarged prostate and can be cured by reducing the size of the prostate. Prostate volume can be used to select treatment, but it is not reasonable to decide whether to treat a patient with LUTS on the basis of prostate size. One of the problems with symptom-based treatment is that LUTS is not gender specific. Questions about LUTS in patients with BPH may elicit very inconsistent responses, and numeric improvement in symptom score is not proportional to how bothered the patient is. Bother, not symptom score or objective measures such as postvoid residual urine and uroflowmetry, is what drives the decision-making process in BPH management. The most recent international guidelines for BPH treatment emphasize that the degree to which the patient is bothered is more important than symptom score. More than a third of all elderly men (and women) have moderate or severe LUTS, and not all of them should receive treatment. In the future, measuring bother due to LUTS and impact on the patients' quality of life with the BPH impact should be imperative and central to treatment decisions.