Transition zone volume and transition zone ratio: predictor of uroflow response to finasteride therapy in benign prostatic hyperplasia patients

The cutoff value of transitional zone index predicting the efficacy of dutasteride on subjective symptoms in patients with benign prostate hyperplasia

OBJECTIVES

We investigated the efficacy of dutasteride add-on therapy to α-1 adrenoceptor antagonists in patients with benign prostate hyperplasia (BPH) in relation to the transitional zone index (TZI) and evaluated the cutoff value of TZI that predicted improvements of subjective symptoms at 6 months.

METHODS

Male BPH patients with prostate volume (PV) ≥ 30 mL receiving dutasteride 0.5 mg/d for 6 months as add-on therapy along with α-1 adrenoceptor antagonists were enrolled. PV, transitional zone volume (TZV), TZI, International Prostate Symptom Score (IPSS), and uroflowmetry parameters before and at 6 months with dutasteride add-on treatment were evaluated.

RESULTS

Eighty-three patients were included. The changes of total IPSS, IPSS voiding subscore, IPSS quality of life score, and voided volume were significantly correlated with TZI. Among baseline parameters, TZV and TZI were significantly associated with the changes of total IPSS in univariate analysis, and only TZI remained as an independent predictive factor for improving total IPSS in multivariate analysis (odds ratio -8.3, P = .048). The cutoff point of TZI for predicting an improvement of the total IPSS by 6 points or more was 0.67 (area under the curve 0.71, sensitivity 0.62, specificity 0.79).

CONCLUSIONS

A higher TZI was significantly associated with improvement of subjective symptoms but not uroflowmetric findings for BPH patients with 6 months of dutasteride add-on therapy along with α-1 adrenoceptor antagonists, and the predictive value of TZI for effective dutasteride add-on therapy was higher than 0.67. BPH patients using α-1 adrenoceptor antagonists with a TZI higher than 0.67 can be good candidates for add-on dutasteride therapy.

Association Between Prostate Zonal Volume and Erectile Dysfunction in Patients With Benign Prostatic Hyperplasia

Introduction

The impact of prostate zonal volume on erectile function and penile Doppler parameters is not yet settled.

Aim

To assess the association between prostate zonal volume and erectile dysfunction in patients with benign prostatic hyperplasia.

Methods

This cross-sectional analytical study included 70 men (aged ≥ 40 years). Of them, 60 patients were assigned to 3 study groups (n = 20/each): group (A) patients who had lower urinary tract symptoms (LUTSs) and erectile dysfunction (ED), group (B) patients who had LUTSs with no ED, group (C) patients who had ED with no LUTS, and other 10 age-matched patients who had no LUTS or ED acted as a control group (D). All patients were subjected to detailed medical and sexual history. International prostate symptom score (IPSS) was used to assess LUTSs, and international index of erectile function (IIEF) was used to assess ED.

Main Outcome Measure

Transrectal ultrasound and penile Doppler ultrasound were used to assess zonal anatomy of the prostate and the vascular pattern of erection.

Results

There was a significant difference in IPSS between group A (26) and B (19) (P < .05). Each of groups A and C had significant lower peak systolic velocity (PSV) than each of groups B and D (P < .001/each). There was a significant positive correlation between transitional zone index (TZI) and IPSS (r = 0.71, P < .01), and significant negative correlation between TZI and both of IIEF (r = -0.48, P < .05) and PSV (r = -0.606, P < .05).

Conclusion

This study clearly demonstrated that there were significant correlations between increased transitional zone volume, TZI, and decreased both of IIEF score and PSV.

Qalawena MM, Al-Shatouri MA, Motawaa MA, et al. Association Between Prostate Zonal Volume and Erectile Dysfunction in Patients With Benign Prostatic Hyperplasia. Sex Med 2020;8:205–213.

Factors Associated With Early Recovery of Stress Urinary Incontinence Following Holmium Laser Enucleation of the Prostate in Patients With Benign Prostatic Enlargement

Purpose

To investigate factors associated with early recovery of stress urinary incontinence (SUI) following holmium laser enucleation of the prostate (HoLEP) in patients with benign prostatic enlargement (BPE).

Methods

The medical records of 393 patients who underwent HoLEP for BPE were retrospectively reviewed. Patients with SUI following HoLEP were selected and divided into 2 groups: those who experienced early recovery of SUI and those who experienced persistent SUI. Recovery of SUI within 1 month after HoLEP was defined as early, and SUI that remained present after 1 month was defined as persistent. Preoperative clinical and urodynamic factors, as well as perioperative factors, were compared between groups.

Results

SUI following HoLEP was detected in 86 patients. Thirty-three patients exhibited recovery of SUI within 1 month, and SUI remained present in 53 patients after 1 month. Multivariate analysis showed that the transition zone prostate volume (odds ratio [OR], 5.354; 95% confidence interval [CI], 1.911–14.999; P=0.001) and the enucleation ratio (OR, 8.253; 95% CI, 1.786–38.126; P=0.007) were significantly associated with early recovery of SUI.

Conclusions

Early recovery of SUI within 1 month following HoLEP was associated with transition zone prostate volume and the enucleation ratio.

Prostatic urethral length as a predictive factor for surgical treatment of benign prostatic hyperplasia: a prospective, multiinstitutional study

Background

We hypothesized that prostatic anatomical factors may affect the progression of benign prostatic hyperplasia (BPH) and analyzed whether prostatic anatomical factors could be predictive of the risk of surgery.

Materials and methods

From February to October 2014, 679 men older than 40 years who had lower urinary tract symptoms and enlarged prostates were enrolled from five medical centers. Patients' medical characteristics, serum prostate-specific antigen levels, transrectal ultrasound (TRUS) results, and uroflowmetry were analyzed. Using TRUS in all patients, the total prostate volume, transitional zone volume, prostatic urethral length, transitional zone urethral length, intravesical prostatic protrusion, and prostatic urethral angle were measured. Logistic regression analysis was used to determine factors associated with the risk of surgery. Receiver operating characteristic curves were used to determine cutoff values for significant variables.

Results

Of 679 patients, 37 (5.4%) underwent BPH-related surgery. Prostatic urethral length and transitional zone urethral length were independently associated with the risk of surgery. Age, serum prostate-specific antigen levels, peak flow rate, postvoid residual urine, and other anatomical factors determined by TRUS were not statistically significant with respect to the risk of surgery. Using receiver operating characteristic curve–based predictions, the best cutoff values for prostatic and transitional zone urethral length were 4.53 cm (sensitivity: 83.3%, specificity: 61.6%) and 3.35 cm (sensitivity: 83.3%, specificity: 77.9%), respectively.

Conclusions

This study showed that patients with BPH with longer prostatic and transitional zone urethral lengths had a higher risk of surgery. Prostatic and transitional zone urethral length may be useful predictive factors for medical treatment failure in patients with BPH.

In vivo evaluation of hot water extract of Acorus gramineus root against benign prostatic hyperplasia

BACKGROUND

Acorus gramineus has been reported to exhibit various pharmacological effects including inhibition of cholesterol synthesis, enhancement of lipid metabolism, prevention of dementia and inhibition of mast cell growth. According to the Chinese compendium of materia media, it has been reported that Acorus spp. is effective for sedation, dementia prevention as well as diuretic effect. In addition, it showed more than equivalent activity compared to furosoemide, a drug known to be effective in diuretic action in animal model study. However, their effectiveness against benign prostatic hyperplasia (BPH) of Acorus gramineus has not been reported. This study was designed to evaluate the effect of Acorus gramineus root hot water extract (AG) against BPH in vivo.

METHODS

Male rats, 10 weeks of age and weighing 405 g ± 10 g, were used for this study. Biomarkers were evaluated including prostate weight, prostate weight ratio, hormonal changes, 5-α reductase type II androgen receptor (AR) of the prostate gland and anti-oxidant activation factors related to BPH. These biomarkers were measured in vivo test.

RESULTS

AG showed significant effect at the 250 and 500 mg/kg/day in rats. Groups treated with AG displayed significantly lower levels of prostate gland weight (0.79 g) compared to the BPH induced group (1.19 g). Also, dihydrotestosterone (DHT) level was decreased from 61.8 to 100% and androgen receptor expression level was decreased from 111 to 658%. Any hematological toxicity of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) level wasn't observed.

CONCLUSION

This study indicated that AG was effective for reducing BPH symptoms.

TRIAL REGISTRATION

Not applicable.

Clinical value of prostate segmentation and volume determination on MRI in benign prostatic hyperplasia

Benign prostatic hyperplasia (BPH) is a nonmalignant pathological enlargement of the prostate, which occurs primarily in the transitional zone. BPH is highly prevalent and is a major cause of lower urinary tract symptoms in aging males, although there is no direct relationship between prostate volume and symptom severity. The progression of BPH can be quantified by measuring the volumes of the whole prostate and its zones, based on image segmentation on magnetic resonance imaging. Prostate volume determination via segmentation is a useful measure for patients undergoing therapy for BPH. However, prostate segmentation is not widely used due to the excessive time required for even experts to manually map the margins of the prostate. Here, we review and compare new methods of prostate volume segmentation using both manual and automated methods, including the ellipsoid formula, manual planimetry, and semiautomated and fully automated segmentation approaches. We highlight the utility of prostate segmentation in the clinical context of assessing BPH.

Clinical significance of peripheral zone thickness in men with lower urinary tract symptoms/benign prostatic hyperplasia

OBJECTIVE

To evaluate the clinical impact of prostate peripheral zone thickness (PZT), based on presumed circle area ratio (PCAR) theory, on urinary symptoms in men with lower urinary tract symptoms/benign prostatic hyperplasia (LUTS/BPH) as a novel prostate parameter.

PATIENTS AND METHODS

Medical records were obtained from a prospective database of first-visit men with LUTS/BPH. Age, international prostate symptom score (IPSS), overactive bladder symptom score (OABSS), maximum urinary flow rate (Qmax ), and post-void residual urine volume (PVR) were assessed. Total prostate volume (TPV), transition zone volume (TZV), transition zone index (TZI), and PZT were measured by transrectal ultrasonography. Reliability analysis was also performed.

RESULTS

In all, 1009 patients were enrolled for the analysis. The mean (sd) PZT was 11.10 (2.50) mm, and patients were classified into three groups PZT thickness groups; PZT <9.5 mm, ≥9.5 to <13 mm, and ≥13 mm. As the PZT became smaller, all urinary symptom scores including IPSS, quality of life (QoL), and OABSS significantly increased. Uroflowmetry variables, such as Qmax and PVR, also showed significant differences. PZT showed a high intra-class correlation coefficient (0.896). Multivariate analysis revealed that the PZT was independently associated with IPSS (P < 0.001), QoL (P = 0.003), OABSS (P = 0.001), and PVR (P = 0.001), but PZT influence on Qmax was only of borderline significance (P = 0.055).

CONCLUSION

PZT is a novel, easy-to-measure prostate parameter that is significantly associated with urinary symptoms. Our present findings suggest that clinical usefulness of PZT should be further validated for managing men with LUTS/BPH.

Prostate volumes derived from MRI and volume-adjusted serum prostate-specific antigen: correlation with Gleason score of prostate cancer

OBJECTIVE

The purpose of this article is to study relationships between MRI-based prostate volume and volume-adjusted serum prostate-specific antigen (PSA) concentration estimates and prostate cancer Gleason score.

MATERIALS AND METHODS

The study included 61 patients with prostate cancer (average age, 63.3 years; range 52-75 years) who underwent MRI before prostatectomy. A semiautomated and MRI-based technique was used to estimate total and central gland prostate volumes, central gland volume fraction (central gland volume divided by total prostate volume), PSA density (PSAD; PSA divided by total prostate volume), and PSAD for the central gland (PSA divided by central gland volume). These MRI-based volume and volume-adjusted PSA estimates were compared with prostatectomy specimen weight and Gleason score by using Pearson (r) or Spearman (ρ) correlation coefficients.

RESULTS

The estimated total prostate volume showed a high correlation with reference standard volume (r = 0.94). Of the 61 patients, eight (13.1%) had a Gleason score of 6, 40 (65.6%) had a Gleason score of 7, seven (11.5%) had a Gleason score of 8, and six (9.8%) had a Gleason score of 9 for prostate cancer. The Gleason score was significantly correlated with central gland volume fraction (ρ = -0.42; p = 0.0007), PSAD (ρ = 0.46; p = 0.0002), and PSAD for the central gland (ρ = 0.55; p = 0.00001).

CONCLUSION

Central gland volume fraction, PSAD, and PSAD for the central gland estimated from MRI examinations show a modest but significant correlation with Gleason score and have the potential to contribute to personalized risk assessment for significant prostate cancer.

Finasteride for benign prostatic hyperplasia

BACKGROUND

Benign prostatic hyperplasia (BPH), a non-malignant enlargement of the prostate in aging men, can cause bothersome urinary symptoms (intermittency, weak stream, straining, urgency, frequency, incomplete emptying). Finasteride, a five-alpha reductase inhibitor (5ARI), blocks the conversion of testosterone to dihydrotestosterone, reduces prostate size, and is commonly used to treat symptoms associated with BPH.

OBJECTIVES

To compare the clinical effectiveness and harms of finasteride versus placebo and active controls in the treatment of lower urinary tract symptoms (LUTS).

SEARCH STRATEGY

We searched The Cochrane Library (which includes CDSR (Cochrane Database of Systematic Reviews), DARE (Database of Abstracts of Reviews of Effects), HTA (Heath Technology Assessments), and CENTRAL (Cochrane Central Register of Controlled Trials, and which includes EMBASE and MEDLINE), LILACS (Latin American and Caribbean Center on Health Sciences Information) and Google Scholar for randomized, controlled trials (RCTs). We also handsearched systematic reviews, references, and clinical-practice guidelines.

SELECTION CRITERIA

Randomized trials in the English language with placebo and/or active arms with a duration of at least 6 months.

DATA COLLECTION AND ANALYSIS

JT extracted the data, which included patient characteristics, outcomes, and harms. Our primary outcome was change in a validated, urinary symptom-scale score, such as the AUA/IPSS. A clinically meaningful change was defined as 4 points. We also categorized outcomes by trial lengths of ≤ 1 year (short term) and > 1 year (long term).

MAIN RESULTS

Finasteride consistently improved urinary symptom scores more than placebo in trials of > 1 year duration, and significantly lowered the risk of BPH progression (acute urinary retention, risk of surgical intervention, ≥ 4 point increase in the AUASI/IPSS). In comparison to alpha-blocker monotherapy, finasteride was less effective than either doxazosin or terazosin, but equally effective compared to tamsulosin. Both doxazosin and terazosin were significantly more likely than finasteride to improve peak urine flow and nocturia, versus finasteride. Versus tamsulosin, peak urine flow and QoL improved equally well versus finasteride. However, finasteride was associated with a lower risk of surgical intervention compared to doxazosin, but not to terazosin, while finasteride and doxazosin were no different for risk of acute urinary retention. Two small trials reported no difference in urinary symptom scores between finasteride and tamsulosin. Finasteride + doxazosin and doxazosin monotherapy improved urinary symptoms equally well (≥ 4 point improvement).For finasteride, there was an increased risk of ejaculation disorder, impotence, and lowered libido, versus placebo. Versus doxazosin, finasteride had a lower risk of asthenia, dizziness, and postural hypotension, and versus terazosin, finasteride had a significant, lower risk of asthenia, dizziness, and postural hypotension.

AUTHORS' CONCLUSIONS

Finasteride improves long-term urinary symptoms versus placebo, but is less effective than doxazosin. Long-term combination therapy with alpha blockers (doxazosin, terazosin) improves symptoms significantly better than finasteride monotherapy. Finasteride + doxazosin improves symptoms equally - and clinically - to doxazosin alone. In comparison to doxazosin, finasteride + doxazosin appears to improve urinary symptoms only in men with medium (25 to < 40 mL) or large prostates (≥ 40 mL), but not in men with small prostates (25 mL).Comparing short to long-term therapy, finasteride does not improve symptoms significantly better than placebo at the short term, but in the long term it does, although the magnitude of differences was very small (from < 1.0 point to 2.2 points). Doxazosin improves symptoms better than finasteride both short and long term, with the magnitude of differences ∼2.0 points and 1.0 point, respectively. Finasteride + doxazosin improves scores versus finasteride alone at both short and long term, with mean differences ∼2.0 points for both time points. Finasteride + doxazosin versus doxazosin improves scores equally for short and long term.Drug-related adverse effects for finasteride are rare; nevertheless, men taking finasteride are at increased risk for impotence, erectile dysfunction, decreased libido, and ejaculation disorder, versus placebo. Versus doxazosin, which has higher rates of dizziness, postural hypotension, and asthenia, men taking finasteride are at increased risk for impotence, erectile dysfunction, decreased libido, and ejaculation disorder. Finasteride significantly reduces asthenia, postural hypotension, and dizziness versus terazosin. Finasteride significantly lowers the risk of asthenia, dizziness, ejaculation disorder, and postural hypotension, versus finasteride + terazosin.

Detection bias due to the effect of finasteride on prostate volume: a modeling approach for analysis of the Prostate Cancer Prevention Trial

BACKGROUND

The Prostate Cancer Prevention Trial (PCPT) demonstrated a 24.8% reduction in the 7-year prevalence of prostate cancer among patients treated with finasteride (5 mg daily) compared with that among patients treated with placebo; however, a 25.5% increase in the prevalence of high-Gleason grade tumors was observed, the clinical significance of which is unknown. One hypothesized explanation for this increase is that finasteride reduced prostate volume, leading to detection of more high-grade tumors due to increased sampling density. This possibility was investigated in an observational reanalysis of the PCPT data, with adjustment for sampling density.

METHODS

A logistic model for the association of high-grade (Gleason score 7-10) prostate cancer with baseline covariates and/or baseline covariates plus prostate volume and number of cores obtained at biopsy was developed using the placebo group (n = 4775) of the PCPT. This model was then applied to the finasteride group (n = 5123) to compare the predicted and observed numbers of high-grade tumors in that group. In a second approach, odds ratios (ORs) for prostate cancer in the finasteride versus placebo groups calculated from binary and polytomous logistic regression models that contained or excluded covariates for gland volume and number of needle cores were compared.

RESULTS

Median prostate volume was 25% lower in the finasteride group (median = 25.1 cm3) than in the placebo group (median = 33.5 cm3). The logistic model developed in the placebo group showed that the likelihood of detection of high-grade prostate cancer decreased as volume increased (for each 10 cm3 increase in prostate volume, OR = 0.81, 95% confidence interval [CI] = 0.74 to 0.90). Based on this model, 239 high-grade prostate cancers were predicted in the finasteride group, whereas 243 were observed, a non-statistically significant difference. Among all participants, the odds ratios for high-grade cancer in the finasteride versus placebo groups decreased from 1.27 (95% CI = 1.05 to 1.54) with adjustment for baseline covariates to 1.03 (95% CI = 0.84 to 1.26) following additional adjustment for gland volume and number of biopsy cores in binary outcome models and from 1.14 (95% CI = 0.94 to 1.38) to 0.88 (95% CI = 0.72 to 1.09) following these adjustments in the polytomous models.

CONCLUSIONS

Although analyses using postrandomization data require cautious interpretation, these results suggest that sampling density bias alone could explain the excess of high-grade cancers among the finasteride-assigned participants in the PCPT.

The impact of targeted training, a dedicated protocol and on-site training material in reducing observer variability of prostate and transition zone dimensions measured by transrectal ultrasonography, in multicentre multinational clinical trials of men with symptomatic benign prostatic enlargement

OBJECTIVE

To assess the variability of a standardized protocol of transrectal ultrasonography (TRUS), with targeted training, and compare it to the variability in other multicentre clinical trials, as TRUS-estimated total prostate volume (TPV) and transition zone volume (TZV) are considered important efficacy endpoints in assessing new drug therapies for benign prostatic enlargement (BPE), but standardizing TRUS remains a challenge in such studies.

PATIENTS AND METHODS

In all, 174 patients with BPE in the placebo arm of a 30-centre clinical trial were analysed at baseline, 13 and 26 weeks with TRUS, to extract TPV and TZV values. All TRUS operators received training in the standardized methods, which was supplemented at the outset by a compact disc-based video.

RESULTS

The mean (sd) changes from baseline in TPV at 13 and 26 weeks were - 2.9 (8.9) and -1.9 (8.5) mL, respectively; the respective mean changes from baseline in TZV were -1.2 (6.4) and + 0.7 (7.8) mL. For TPV, 80% of the measurements had differences of + 5.2 to -13.4 mL at 13 weeks, and + 8.0 to - 10.9 mL at 26 weeks. For TZV, 80% of the differences were + 5.8 to - 7.4 at 13 weeks, and + 9.3 to -6.5 mL at 26 weeks.

CONCLUSION

The performance of TRUS compared favourably with similar published multicentre studies, which we suggest relates in part to the careful implementation of the protocol. We showed that diligent implementation of a detailed protocol, supplemented by targeted training of investigators and provision of on-site training material, promoted consistent acquisition and successful derivation of key clinical trial endpoints. Quantifying the variability of such endpoints will enable us to track deployment quality for future clinical trials, and will ensure that trials are sufficiently powered to define small changes in prostate size.

The effect of dutasteride on the peripheral and transition zones of the prostate and the value of the transition zone index in predicting treatment response

PURPOSE

We determined the effects of dutasteride on transition and peripheral zone volume, and the clinical value of the transition zone index in men with benign prostatic hyperplasia.

MATERIALS AND METHODS

A total of 2,802 men 50 years or older with diagnosed benign prostatic hyperplasia, American Urological Association symptom index score 12 or greater, total prostate volume 30 cc or greater, prostate specific antigen 1.5 ng/ml or greater and 10 ng/ml or less, and peak urinary flow rate 15 ml per second or less were randomized to receive 0.5 mg dutasteride daily or placebo for 2 years. Total prostate and transition zone volume was measured with transrectal ultrasound at baseline and 4 times during the 2-year period. Peripheral zone volume (total prostate volume minus transition zone volume) and the transition zone index (transition zone volume/total prostate volume) were calculated. Patients were stratified into tertiles according to baseline total prostate and transition zone volume, and the transition zone index.

RESULTS

At 24 months dutasteride significantly decreased total prostate volume from baseline (p <0.0001). There were similar decreases in transition and peripheral zone volume (approximately 25%). In men receiving placebo high baseline total prostate and transition zone volume, and transition zone index were associated with poor 2-year outcomes, ie a low peak urinary flow rate, high American Urological Association symptom index scores, and an increased frequency of acute urinary retention and benign prostatic hyperplasia related surgery. Improvements in outcomes with dutasteride vs placebo were greatest in men with the highest baseline total prostate and transition zone volume, and transition zone index. In men with low (30 to less than 42 cc) and intermediate (42 to less than 58 cc) baseline total prostate volume the benefits of dutasteride therapy were only significant in the intermediate (0.4 to less than 0.55) and high (0.55 to less than 1.0) transition zone index tertiles.

CONCLUSIONS

Total prostate and transition zone volume, and the transition zone index are directly related to benign prostatic hyperplasia progression. The transition zone index may add value to transition zone volume alone for predicting outcomes. Dutasteride decreased transition and peripheral zone volume equally, supporting a known therapeutic role in benign prostatic hyperplasia and a possible preventive role in prostate cancer.

Benign Prostatic Hyperplasia: A Review and Ultrasound Classification

Benign prostatic hyperplasia (BPH) is reviewed, including definition,natural history, diagnosis, and brief discussion of clinical management. Transrectal ultrasound is used to demonstrate the gross anatomy and natural history of BPH and its role in diagnosis and treatment strategies. A potentially useful ultrasound classification of BPH based on the gross anatomic classification of Randall is illustrated.

Correlations between longitudinal changes in transitional zone volume and measures of benign prostatic hyperplasia in a population-based cohort

OBJECTIVE

To determine whether measures of transitional zone volume (TZV) are more strongly associated than total prostate volume with longitudinal urologic outcomes.

METHODS

In 1990, 2,115 randomly selected Caucasian men from Olmsted County, Minnesota (USA) completed validated questionnaires during a home visit. A 25% subsample underwent clinical evaluation that included transrectal ultrasonography, assessment of serum prostate-specific antigen levels, and maximum urinary flow rates. Examinations and questionnaires were repeated biennially through 2004. TZV measures were taken at the fifth through eighth visits. Men with at least one TZV measurement were included in this study (n=336).

RESULTS

Changes in TZV correlated weakly with changes in peak urinary flow rate and urinary symptoms. After accounting for age and change in total prostate volume, change in TZV added no information to models that predict changes in urinary symptoms and peak urinary flow rates. Men who experienced the most rapid annual changes in TZV were not more likely to experience more rapid changes in urinary symptoms or maximum flow rate.

CONCLUSION

Tracking changes in TZV over time may be unlikely to provide a good surrogate measure for the development of benign prostatic hyperplasia.

RELATIONSHIP BETWEEN PROSTATE SPECIFIC ANTIGEN AND INDEXES OF PROSTATE VOLUME IN JAPANESE MEN

PURPOSE

We determined the relationship between serum prostate specific antigen (PSA) and indexes of prostate volume in Japanese men, and compared that relationship with the one in white men.

MATERIALS AND METHODS

Data on a clinical cohort of 535 Japanese men with at least moderate lower urinary tract symptoms (LUTS) and clinical benign prostatic hyperplasia were examined. PSA, and total and transition zone prostate volume were related to age and linear regression analyses were performed to analyze the relationship between PSA and volume indexes.

RESULTS

The group of 535 men with a median age of 68 years had a median serum PSA of 1.5 ng/ml, and a median total and transition zone volume of 26.8 and 8.8 ml, respectively. PSA, total prostate volume and transition zone volume increased almost linearly with age. On univariate regression with age with each successive decade total prostate volume increased by 10.65% (95% CI 5.4 to 16.2), transition zone volume increased by 20.84% (95% CI 11.84 to 30.56) and the transition zone index increased by 3.1% (95% CI 1.66 to 4.57). On multivariate analysis the PSA-total prostate volume relationship was statistically independent of age. The study suggests that Japanese men might produce or release more PSA per unit prostate volume than white men.

CONCLUSIONS

Japanese men with LUTS and clinical benign prostatic hyperplasia but no evidence of prostate cancer might produce and/or release more PSA per unit prostate volume than white men. To our knowledge the cutoffs for PSA and prostate volume to predict the response to LUTS therapy and the development of complications in Japanese men are unknown. Future studies in Japanese men are needed to identify these cutoffs.

Transurethral microwave thermotherapy: an alternative to medical management in patients with benign prostatic hyperplasia?

Transurethral microwave thermotherapy (TUMT) is being increasingly considered as an alternative to medical management with alpha-blockers or finasteride in patients with lower urinary tract symptoms (LUTS) of benign prostate hyperplasia (BPH). Enduring clinical benefits have been demonstrated after a single 1-hour microwave treatment session under topical anesthesia, and the associated morbidity is low. Optimal results are obtained with the delivery of high thermal doses and accurate targeting of microwave energy. Extensive evidence from randomized clinical trials supports the safety and efficacy of both microwave treatment and medical management, but randomized trial data have only recently become available directly comparing these two approaches to BPH treatment. These data indicate that greater long-term improvements in symptoms, peak urinary flow rates, and quality of life are attained with microwave treatment than with alpha-blockade. Furthermore, the actuarial rate of treatment failure is markedly lower in patients undergoing microwave v alpha-blocker treatment. However, the onset of action of alpha-blocker treatment is more rapid. The principal limitations of alpha-blockade are side effects and lack of efficacy leading to treatment failure in some patients. The maximal effects of finasteride are modest and require a period of months to be manifested, although the side effect profile and tolerability of this agent are favorable. Neoadjuvant and adjuvant alpha-blocker therapy can accelerate symptom and flow rate improvement after TUMT. In contrast to medical management, microwave treatment is highly versatile, allowing patients over a broad range of baseline symptom severities and prostate sizes to be treated with a high probability of success.

Does long-term finasteride therapy affect the histologic features of benign prostatic tissue and prostate cancer on needle biopsy? PLESS Study Group. Proscar Long-Term Efficacy and Safety Study

OBJECTIVES

Finasteride, a common agent used to treat benign prostatic hyperplasia (BPH), inhibits 5-alpha-reductase. Testosterone is converted by 5-alpha-reductase to the more potent dihydrotestosterone, which is the primary androgen in the prostate. Leuprolide is a stronger antiandrogen that is used to downstage prostate cancer before radical prostatectomy. Leuprolide induces marked atrophy of prostate carcinoma cells, which sometimes makes pathologic diagnosis of cancer difficult, although evaluation at radical prostatectomy is easier than at biopsy. It is unknown whether finasteride produces similar changes, which would result in greater diagnostic difficulty because such changes would be seen on biopsy to rule out cancer in men with suspicious clinical findings treated for BPH. The current study investigated the histologic effects of finasteride therapy on human prostate cancer and benign prostatic tissue on needle biopsy.

METHODS

In blinded manner, we reviewed 53 needle biopsy specimens showing prostate carcinoma (35 treated with finasteride, 18 with placebo). Also reviewed in blinded manner were 50 benign needle biopsy specimens (25 treated with finasteride, 25 with placebo). The Gleason score, number of cores involved, percentage cancer involvement in a core, percentage of atrophic changes in cancer cells, presence of mitoses, blue-tinged mucinous secretions, prominent nucleoli, and high-grade prostatic intraepithelial neoplasia were documented for each case in the cancer group. The percentage of atrophy, basal cell hyperplasia, transitional metaplasia, chronic inflammation, and stromal proliferation was documented for each case in the benign group.

RESULTS

No significant histologic differences were present in either the benign or cancer group between cases treated with finasteride and placebo.

CONCLUSIONS

We conclude that finasteride treatment for BPH does not cause difficulty in the diagnosis of cancer in prostate needle specimens. It is possible that there are severely atrophic areas resulting from finasteride treatment that are undersampled. However, the conclusion that cancer seen on needle biopsy in men treated with finasteride is unaltered and readily identified as cancer remains valid.

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.

Transurethral microwave thermotherapy: what role should it play versus medical management in the treatment of benign prostatic hyperplasia?

Both transurethral microwave thermotherapy (TUMT) and medical management by alpha-blockade or 5-alpha-reductase inhibition are increasingly being considered as alternatives to surgery for treatment of patients with benign prostatic hyperplasia (BPH). We review current evidence supporting the effectiveness and safety of TUMT and medical management. Factors for consideration in appropriately selecting patients for TUMT versus medical management are suggested. Available data indicate that TUMT confers greater long-term benefits than medical management as judged by symptom score and peak urinary flow rate improvements. TUMT-associated morbidity is comparatively low. Alpha-blockade affords more rapid relief than TUMT for patients with BPH; however, other strategies such as the use of temporary intraurethral endoprostheses during the acute post-TUMT recovery period may diminish or abolish the differences in time-course of symptom and flow rate improvement between TUMT and alpha-blockade. 5-Alpha-reductase inhibition with finasteride offers a favorable side-effect profile, although the magnitude of symptom and flow rate improvements is modest, and maximal effects of finasteride do not become manifest until after several months of treatment. As TUMT continues to evolve, increasing attention is being accorded the delivery of high thermal doses and precise targeting of the thermal energy delivered. The development of alpha-blockers with a more favorable side-effect profile continues to be a major focus of investigation. The potential clinical utility of combination therapy with TUMT and alpha-blockade is currently under investigation.

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.

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.

Treatment of benign prostatic hyperplasia. A pharmacoeconomic perspective

Men with moderate symptoms of benign prostatic hyperplasia (BPH) are the best candidates for medical treatment, while surgery is usually indicated for patients with severe symptoms. Men with mild symptoms do not usually need treatment, but they might be re-evaluated annually if desirable. Finasteride, which produces selective hormonal deprivation, is now established as a well tolerated drug for the long term medical therapy of BPH. Recent studies suggest that finasteride is most effective in men with large prostates (> 40 ml), and the drug should probably be reserved for these patients. alpha-Blockers work in men with small or large prostates, and their rapid onset of action facilitates the identification of responders. alpha-Blockers are more effective than finasteride during the first year of treatment, but only finasteride induces regression of the prostate and offers increased efficacy over time. Even if drug therapy reduces the need for prostate surgery, the total economic cost of BPH treatment is likely to rise because of the increasing application of medical treatment. The magnitude of this increase depends largely on what percentage of the male population embark on long term therapy, at what age treatment is started, and how successful it is. At present, the answers to these questions are largely unknown. The personal economic expenses for men who begin long term medical therapy will probably be an important factor in deciding how common drug treatment for BPH will become in the future. For many men, the main benefit of drug treatment will be the relief of urinary symptoms, but whether this improvement is substantial enough to improve their overall quality of life has not yet been clearly demonstrated in controlled studies.

Transition zone ratio and prostate-specific antigen density: the index of response of benign prostatic hypertrophy to an alpha blocker

BACKGROUND

The aim of the present study was to determine whether the indices of transrectal ultrasonography (TRUS) are related to the clinical response to tamsulosin, a long-acting selective alpha 1-blocker.

METHODS

Sixty patients with symptomatic benign prostatic hypertrophy (BPH) were treated with tamsulosin hydrochloride (0.2 mg/day) for 2 months. The findings on TRUS and uroflowmetry and the AUA symptom score before treatment were compared with those obtained at the end of the 2 month treatment period. For the indices of TRUS, transition zone (TZ) volume, transition zone ratio (TZ ratio = TZ volume/total prostate volume), total prostate volume, and prostate specific antigen density (PSAD) were calculated.

RESULTS

There was a significant correlation between the pretreatment TZ ratio and the residual urine volume (r = 0.421, P = 0.0005). Patients with a lower TZ ratio and/or PSAD responded well to the treatment. The correlation between the PSAD value and the percent change in peak urinary flow rate was statistically significant (r = -0.432, P = 0.0009).

CONCLUSION

TRUS provides simple parameters of PSAD that can be used to predict the response of patients to tamsulosin hydrochloride.

Treatment of benign prostatic hyperplasia with 5-alpha-reductase inhibitor: morphological changes in patients who fail to respond

AIMS

To describe the prostatic adenectomy specimens of six patients with symptomatic benign prostatic hyperplasia (BPH) who failed to respond to long term treatment with a 5-alpha-reductase inhibitor, finasteride.

METHODS

Histological sections from six cases of BPH who had been treated with finasteride were investigated. Five patients were prescribed 5 mg finasteride daily for six months and one patient 5 mg daily for 12 months. The patients underwent adenectomy as their urethral obstruction failed to resolve. Twenty cases of untreated BPH served as controls.

RESULTS

In patients taking finasteride for six months the prostatic adenectomy specimens showed a reduction in the size of the prostate and an increase in the stroma:epithelial and stroma:lumen ratios compared with controls. The size of the ducts and acini was not as uniform as in the controls. In particular, some ducts and acini were still lined by a bistratified epithelium similar to that found in controls but lacked undulations at the epithelial border; other ducts/acini were atrophic. Some scattered clusters of small acini with a focally fragmented basal cell layer were observed in two of the five treated cases. One prostatic adenectomy specimen, from the patient treated for one year, showed extensive lobular atrophy and diffuse squamous and transitional cell metaplasia. At the periphery of the transition zone, there was a complex intra-acinar papillary-cribriform proliferation of clear cells without nuclear atypia, similar to clear cell papillary hyperplasia. The periurethral region showed stromal nodules in both patients and controls.

CONCLUSIONS

Morphological evaluation of finasteride treated BPH showed changes in the lobules of the transition zone, but not in the periurethral stroma.

A dose-response study of the effect of flutamide on benign prostatic hyperplasia: results of a multicenter study

OBJECTIVES

The objective of this study was to evaluate efficacy, safety, and dose-response profiles of four dosing schemes of flutamide over 24 weeks.

METHODS

Patients were randomized to receive one of the following five treatment regimens for a period of 24 weeks: placebo capsule, flutamide capsules 125 mg twice daily, 250 mg once daily, 250 mg twice daily, and 250 mg three times daily. Patients were then evaluated at baseline (0 weeks) and at 4, 6, 12, 18, and 24 weeks after the start of treatment, and 8 weeks after the end of treatment (32 weeks). Evaluation of efficacy was performed by noting changes in urine flow rate, residual urine volume, symptom score, prostate volume, and prostate-specific antigen level. A total of 372 patients were enrolled into the study at 32 centers (14 centers in the United States and 18 international centers).

RESULTS

Baseline peak urinary flow rate and percent change from baseline in maximum flow rate showed a dose-related increase at 4 and 6 weeks; this increase was significant in the 250 mg three times daily group. At later time points, no significant differences between the flutamide and placebo groups were observed, largely because of the decreasing number of evaluable patients. At 4 and 6 weeks, 25% of patients in the 250 mg three times daily group had more than 3 cc/s increase in uroflow compared to about 10% of placebo patients (P < 0.05). All flutamide-treated groups had a significant decrease in prostate volume from baseline to the last treatment visit compared to placebo and this reduction was dose related (in comparison to placebo: P < 0.05 for 125 mg twice daily and P < 0.001 for all other treatment arms). Median decrease for the flutamide-treated groups ranged from 6% to 23% at 12 weeks and from 14% to 29% at 24 weeks. All treatment groups showed a subsequent increase in prostate volume after treatment was stopped. Furthermore, there was a significant reduction in residual urine volume at 24 weeks only in the 250 mg three times daily group. It increased following cessation of therapy. Urinary symptoms at 6, 12, 18, and 24 weeks did not show any significant difference between placebo and any flutamide dose group. The most common adverse events were nipple and breast tenderness (42% to 52%), diarrhea (29% to 34%), and gynecomastia (14% to 19%). Each of these adverse events had a significantly higher incidence in all flutamide dose groups compared with placebo, but none appeared to occur in a dose-related fashion. Sixteen percent of patients in the placebo group and 25% to 39% of patients in flutamide groups were discontinued due to diarrhea (12% to 17%) or nipple and breast tenderness (4% to 8%). A total of 1% to 3% of patients in various treatment arms discontinued due to deranged liver enzymes (1% for placebo); and 1% to 4% due to impotence (1% for placebo).

CONCLUSIONS

Flutamide reduced the prostate volume in a dose-related fashion and resulted in an increase in peak flow rate at 4 weeks (3% for 250 mg three times daily, P value < 0.05), but the early positive effects did not maintain statistical significance due to an increasing number of dropouts due to adverse events. Effect on postvoid residual volume was observed only at the highest dose and at 24 weeks (median reduction, 23 mL, P < 0.05). Despite volume reduction and early improvement in peak flow rate, there were no significant differences in urinary symptoms among the placebo and flutamide groups. Higher incidences of diarrhea, breast tenderness, and gynecomastia, however, were the main limiting factors in this study and until these problems are overcome, the role of flutamide in the management of benign prostatic hyperplasia remains investigational.