Transurethral microwave thermotherapy: from evidence-based medicine to clinical practice

PURPOSE OF REVIEW: The aim of this article is to provide new clinical data on transurethral microwave thermotherapy, evaluate it in the perspective of evidence-based guidelines and daily practice and investigate the driving forces that determine the current position of thermotherapy for the management of benign prostatic obstruction. RECENT FINDINGS: Recent studies have provided significant evidence regarding the efficacy, safety and durability of thermotherapy. Updated evidence-based clinical guidelines on the management of patients with benign prostatic obstruction have been made available. Surveys have evaluated the acceptance of transurethral microwave thermotherapy from the urological community. In addition, several studies have made major contributions to our knowledge of the translation of evidence to daily practice. SUMMARY: The range of therapeutic options for benign prostatic obstruction continues to widen creating the need for clarity in selection and application of these treatments. High-quality data on transurethral microwave thermotherapy have been published and integrated into clinical guidelines. Considerations on the implementation of guidelines to clinical practice, emergence of new treatments, shift of benign prostatic obstruction therapy, economics and the increasing need to treat patients with different clinical profile during the last decade seem to affect the position of transurethral microwave thermotherapy in the armamentarium of a urological centre. Into this frame, transurethral microwave thermotherapy tailored to selective cases seems to remain an attractive option.     

Modifiable risk factors for benign prostatic hyperplasia and lower urinary tract symptoms: new approaches to old problems

PURPOSE: Benign prostatic hyperplasia is generally not regarded as a preventable disease. However, accumulating evidence suggests that modifiable factors may influence the risk of benign prostatic hyperplasia and lower urinary tract symptoms. MATERIALS AND METHODS: A structured, comprehensive literature review was done to identify modifiable risk factors for benign prostatic hyperplasia and lower urinary tract symptoms among observational studies of older men. RESULTS: Outcome measures used to define benign prostatic hyperplasia in clinical studies include histological analysis of prostate tissue, radiographically determined prostate enlargement, acute urinary retention, decreased urinary flow rate, pressure flow studies consistent with bladder outlet obstruction, history of benign prostatic hyperplasia surgery, physician diagnosed benign prostatic hyperplasia and American Urological Association symptom score or International Prostate Symptom Score. Factors that potentially increase the risk of benign prostatic hyperplasia and lower urinary tract symptoms include obesity and diabetes. Factors that potentially decrease the risk include increased physical activity and moderate alcohol consumption. Other candidate factors for which clear risk patterns have not yet emerged are dyslipidemia, hypertension, smoking, diet and environment. CONCLUSIONS: Obesity, diabetes, physical activity and alcohol intake may substantially influence the risk of benign prostatic hyperplasia and lower urinary tract symptoms in older men. Further analyses of these and other potential modifiable risk factors may identify novel interventions for the prevention, diagnosis and treatment of these highly prevalent conditions.     

To what extent do real life practice studies differ from randomized controlled trials in lower urinary tract symptoms/benign prostatic hyperplasia?

PURPOSE OF THE REVIEW: To compare the real-life practice studies and randomized controlled trials on benign prostatic hyperplasia in order to understand the applications of the data from the two types of study. RECENT FINDINGS: Until recently, much of the available information on benign prostatic hyperplasia has come from randomized controlled trials conducted by secondary care urologists on selected populations of patients, who are likely to represent the more symptomatic among the cohort of men with lower urinary tract symptoms in the community. The strict inclusion criteria in these trials led to uncertainty about the applicability of the results to community populations. Moreover, as patients in randomized controlled trials are specially recruited, rather than being drawn from a general population of men with lower urinary tract symptoms, the calculations of incidence and prevalence rates may not be possible. In the last few years, there have been a few important real-life practice studies such as the Triumph project, the Quadraet study and the ALF-ONE study, which have provided very useful data regarding the incidence and prevalence of lower urinary tract symptoms/benign prostatic hyperplasia, the incidence of acute urinary retention, the impact of therapy on the risk of surgery related to benign prostatic hyperplasia and the predictors of disease progression during treatment with alpha-blocker. SUMMARY: As the results from randomized controlled trials cannot always be generalized to daily urological practice, it is important to complement them with data made available by the real-life practice studies. In order to do that, the salient features in the methodology of both types of study must be understood.     

Update of the minimally invasive therapies for benign prostatic hyperplasia

PURPOSE OF REVIEW: The elevated impact benign prostatic hyperplasia has on patient quality of life has determined continuous research into the development of minimally invasive therapies aimed at restoring or preserving a good quality of life. The purpose of this review is to highlight recent developments in the field of minimally invasive treatment of benign prostatic hyperplasia, and to determine their possible impact on everyday clinical practice. RECENT FINDINGS: Recent publications have described some interesting new therapies and provided data concerning long-term follow up and cost-effectiveness that have been lacking up until now. The review mainly focuses on transurethral microwave thermotherapy, interstitial laser coagulation, transurethral laser ablation, laser prostatectomies (resection and enucleation), transurethral ethanol injection therapy, transurethral electrovaporization, and high-power (80-W) potassium titanyl phosphate laser vaporization. SUMMARY: Recent developments, new approaches and long-term reports of previously described minimally invasive therapies for the treatment of benign prostatic hyperplasia are presented. Cost-effectiveness studies were also carried out to complete the comparison with standard everyday procedures. Currently, transurethral microwave thermotherapy seems to offer the soundest basis for management of the condition, providing the longest term follow up and the largest numbers of studies completed to date. Among surgical alternatives, holmium laser enucleation has gained ground as an encouraging new approach, being similar to standard transurethral resection of the prostate, but reducing perioperative morbidity with the same long-term results. More randomized comparisons correctly conducted need to be undertaken before an accurate general picture is available for the urologist.     

The overlapping lower urinary tract symptoms of benign prostatic hyperplasia and prostatitis

PURPOSE OF REVIEW: To investigate the relationship, diagnosis and treatment of the overlapping lower urinary tract symptoms experienced by men diagnosed with benign prostatic hyperplasia and prostatitis. RECENT FINDINGS: Recent studies have clearly shown that men can suffer from both benign prostatic hyperplasia and prostatitis. Approximately 5-20% of men diagnosed with benign prostatic hyperplasia suffer from prostatitis-like symptoms, while over one third of men diagnosed with benign prostatic hyperplasia have had a diagnosis of prostatitis in the past. Differentiation between these two symptom-based medical conditions can be difficult because of overlapping symptoms, but pain clearly identifies those patients with chronic prostatitis. Treatment for men with co-occurring benign prostatic hyperplasia and prostatitis may include alpha-blockers, 5alpha-reductase inhibitors and phytotherapies (saw palmetto and bee pollen extract), with evidence clearly showing the benefits of alpha-blocker therapy. SUMMARY: Benign prostatic hyperplasia and chronic prostatitis are a common cause of lower urinary tract symptoms and frequently co-occur in older men. The best treatment for men with lower urinary tract symptoms associated with both benign prostatic hyperplasia and prostatitis is alpha-blockers.     

Plant extracts: sense or nonsense?

PURPOSE OF REVIEW: To assess the current role of plant extracts in the medical management of lower urinary tract symptoms due to benign prostatic enlargement/benign prostatic obstruction. RECENT FINDINGS: In 2006, two clinical trials meeting the WHO benign prostatic hyperplasia consensus conference criteria (randomized against placebo/standard therapy, study duration 12 months) were published. One trial compared a saw palmetto extract with placebo. This industry-independent trial published in the New England Journal of Medicine was negative, that is, this saw palmetto extract had no effect on symptoms, Qmax and postvoid residual volume. In another trial, a saw palmetto/urtica combination was compared with tamsulosin. After 12 months, the improvement of symptoms was identical in both study arms. No detailed data were presented, however, on Qmax, postvoid residual or prostate volume. The biological mechanisms of plant extracts in vivo are still unknown and the numerous metaanalyses cannot supplement high-quality prospective trials. SUMMARY: Further prospective studies according to WHO benign prostatic hyperplasia standards are required to reliably determine the role of plant extracts in contemporary lower urinary tract symptoms management and to be able to answer the question in the title: 'plant extracts: sense or nonsense?' Plant extracts are currently not recommended by the American and European Association of Urology benign prostatic hyperplasia guidelines.     

Acute urinary retention: Who is at risk and how best to manage it?

In recent years, we have begun to understand the progressive nature of benign prostatic hyperplasia. By careful analysis of population studies and clinical trials, we can determine the factors most likely to predict progression to one of its most distressing complications, acute urinary retention. Acute urinary retention is a common urologic emergency and causes significant suffering, although rarely has it any serious consequences. Using our knowledge regarding the progression of benign prostatic hyperplasia, new treatment modalities are being assessed for their effectiveness at halting progression and ultimately preventing this distressing condition.     

Clinical guidelines for male lower urinary tract symptoms and benign prostatic hyperplasia

The present article is the abbreviated English translation of the Japanese guidelines for male lower urinary tract symptoms and benign prostatic hyperplasia updated as of the end of 2016. The target patients are men aged >50 years complaining of lower urinary tract symptoms, with or without benign prostatic hyperplasia, and the target readers are non‐urological general physicians and urologists. Mandatory assessment for general physicians is medical history, physical examination, urinalysis and measurement of serum prostate‐specific antigen. Additional mandatory assessment for urologists is symptoms and quality of life assessment by questionnaires, uroflowmetry, residual urine measurement, and prostate ultrasonography. Nocturia requires special attention, as it can result from nocturnal polyuria and/or sleep disturbance rather than lower urinary tract disorders. Functional lower urinary tract disorders with or without benign prostatic hyperplasia are primarily managed by conservative therapy and medications, such as α₁‐blockers and phosphodiesterase‐type 5 inhibitors. Use of other medications or combination pharmacotherapy is to be reserved for urologists. 5α‐Reductase inhibitors and anticholinergics or β3 agonists are indicated for men with enlarged prostates and overactive bladder symptoms, respectively. Surgical intervention for bladder outlet obstruction is considered for persistent symptoms or benign prostatic hyperplasia‐related comorbidities. Surgical modalities should be optimized by the patient's characteristics, performance of equipment and the surgeon's experience.     

A rational approach to benign prostatic hyperplasia evaluation: recent advances

PURPOSE OF REVIEW: In this article we aim to outline the recent advances in the evaluation of a patient with symptoms suggestive of benign prostatic hyperplasia. We define the role of the clinical evaluation and techniques that are evolving for the appropriate management of a patient with benign prostatic hyperplasia. Both non-invasive and invasive investigation techniques are reviewed. RECENT FINDINGS: Initiating early and appropriate treatment is the primary aim of investigation for a patient with lower urinary tract symptoms. Both clinical history and examination and appropriate investigations are vital to establishing a diagnosis. Symptom scores, prostate specific antigen and prostate volume were found to closely relate in predicting the progression of benign prostatic hyperplasia and in recent years increased interest has centred on the progression of this disease principally related to the development of new pharmacotherapy. Despite these positive findings further research is needed to develop reliable tools to predict progression. Newer ultrasound techniques hold promise for the future. Conventional pressure flow studies have a defined role in excluding patients who are less likely to benefit from prostatic surgery by providing information on detrusor function; and non-invasive urodynamic techniques need further evaluation but appear to be promising. SUMMARY: The minimal initial evaluation of a patient with benign prostatic hyperplasia should include a thorough history, digital rectal and neurological examinations, symptom scoring (including quality of life and sexual score) and measurement of serum prostate specific antigen. Other methods should be reserved for more complex situations. Attempts should be made at identifying those patients in whom the disease process is likely to progress.     

Open adenomectomy: past, present and future

PURPOSE OF REVIEW: Open surgery has been the gold standard for the treatment of benign, symptomatic, large volume prostatic hyperplasia. Recent data series, however, have demonstrated that a minimally invasive approach can be used for the treatment of this pathology while duplicating the results of the open technique. This review will describe the different surgical techniques that have been used through the last century for the treatment of benign prostatic hyperplasia, highlighting the advantages and disadvantages of each approach. RECENT FINDINGS: Surgical management for symptomatic benign prostatic hyperplasia has made a journey from an open approach to robotic surgery. Modifications of the gold standard transurethral resection have been incorporated into clinical practice and include bipolar transurethral resection as well as holmium laser resection and potassium titanyl phosphate laser vaporization. Minimally invasive ablative techniques have also been popularized and include transurethral needle ablation and thermotherapy. Most recently, laparoscopy has demonstrated to be a feasible, safe, reproducible technique that can create similar outcomes to an open technique whilst maintaining the advantages of a minimally invasive approach. Although the future will see greater use of robotics, larger series are needed to prove the advantages of this technology. SUMMARY: Minimally invasive approaches for the treatment of symptomatic benign giant prostatic hyperplasia are replacing open surgery, which has been the gold standard for the surgical treatment of this pathology, duplicating its results with a lower morbidity. Recently we have seen a growing amount of experience treating this disease state with laparoscopic/robotics and the advantages it provides may permit the popularization of this technique.     

Phytotherapie bei benignem Prostatasyndrom und Prostatakarzinom

In some countries plant extracts have belonged to the most popular drugs for the treatment of the benign prostatic syndrome (BPS) for decades; however, only few of the large number of published studies meet the criteria of the WHO benign prostatic hyperplasia (BPH) consensus conference. The few placebo-controlled long-term (study period >6 months) studies suggest a positive effect of some extracts (saw palmetto fruit, ??-sitosterol, urtica, rye grass and a saw palmetto/urtica combination) on lower urinary tract symptoms (LUTS), urinary flow rate, post-void residual volume but effects on prostate volume or prostate-specific antigen (PSA) were only inconsistently demonstrable. To date no study has proven an effect on disease progression, such as acute urinary retention or need for surgical interventions. Due to the controversial data various extraction techniques and compositions of various products, neither American, European, British nor German BPH guidelines recommend plant extracts for the indication BPS although some placebo-controlled trials provided encouraging data. Further prospective studies according to WHO standards are required to determine the role of plant extracts for the management of BPS. For the indication of prostate cancer (PCa) plant extracts have been evaluated for disease prevention and management of several tumor stages but none of these studies have provided convincing evidence that plant extracts are superior to placebo and none of the Pica guidelines have recommended their use. Based on current knowledge plant extracts can never supplement evidence-based PCa management and should be used only in addition to the standard treatment. There is no scientific evidence for the use of dietary supplementation with high doses of vitamins or selenium-containing products.     

The role of anticholinergic drugs in men with lower urinary tract symptoms

PURPOSE OF REVIEW: Male lower urinary tract symptoms are often attributed to benign prostatic hyperplasia. However, coexisting overactive bladder may be responsible for storage symptoms in a substantial proportion. Treatment of these symptoms with anticholinergic drugs has been considered hazardous in benign prostatic hyperplasia because of concerns that they may predispose to acute urinary retention. We present recent research evidence on the effectiveness and safety of anticholinergics for male lower urinary tract symptoms. RECENT FINDINGS: Two systematic reviews and a large randomized controlled trial recently evaluated anticholinergic drugs in men with lower urinary tract symptoms. These studies provided good evidence that anticholinergics are effective at improving both urodynamic and patient-reported outcomes. Postvoid residual urine volumes and urine flow rates were not significantly affected, and acute urinary retention was rare. SUMMARY: In men with lower urinary tract symptoms treatment may need to be directed at both the prostate and the bladder, and a pragmatic approach therefore seems appropriate. Men presenting with lower urinary tract symptoms should undergo comprehensive clinical evaluation before benign prostatic hyperplasia is treated, if indicated. Should symptoms fail to resolve, addition of anticholinergic drugs may be considered in the absence of significant postvoid residual urine volumes.     

Lack of value of radioimmunoassay for prostatic acid phosphatase as a screening test for prostatic cancer in patients with obstructive prostatic hyperplasia

We examined the incidence of prostatic cancer in patients with an elevated radioimmunoassay for prostatic acid phosphatase and clinical benign prostatic hyperplasia on digital rectal examination. Of 295 patients screened with prostatic acid phosphatase tests 17 fulfilled the criteria of having an elevated prostatic acid phosphatase, clinically benign prostate and histological examination of the prostatectomy specimen. None of the 17 patients had histological evidence of prostatic cancer. The results confirm the predictions of mathematical models that prostatic acid phosphatase is of no practical value as a screening test for prostatic cancer in patients with clinical benign prostatic hyperplasia.     

改良Madigan术治疗前列腺中叶增生

目的：探讨应用改良Madigan术治疗前列腺中叶增生的疗效。方法：对39例前列腺中叶增生的患者采用联合膀胱颈部切开的改良Madigan前列腺切除术切除增生的前列腺体，同时处理膀胱内病变，术后随访2－24个月，并对结果进行回顾性小说。结果：本组患者手术、恢复均顺利，出院时IPSS平均3.8分，生活质量评分0－2分，最大尿流率14.5－23.5ml/s，剩余尿量＜20ml，术后随访未发现严重并发症。结论：本术式既切除了重度增生突入膀胱内的前列腺中叶及处理了膀胱内的病变， 又保留了尿道粘膜的完整性，是处理前列腺中叶增生的一种较好的方法。     

Dihydrotestosterone and the concept of 5alpha-reductase inhibition in human benign prostatic hyperplasia

OBJECTIVE:The development of the human benign prostatic hyperplasia clearly requires a combination of testicular androgens and aging. Although the role of androgens as the causative factor for human benign prostatic hyperplasia is debated, they undoubtedly have at least a permissive role. The principal prostatic androgen is dihydrotestosterone (DHT). Although not elevated in human benign prostatic hyperplasia, DHT levels in the prostate remain at a normal level with aging, despite a decrease in the plasma testosterone. RESULTS: DHT is generated by reduction of testosterone. Two isoenzymes of 5alpha-reductase have been discovered. Type 1 is present in most tissues of the body where 5alpha-reductase is expressed and is the dominant form in sebaceous glands. Type2 5alpha-reductase is the dominant isoenzyme in genital tissues, including the prostate. Finasteride is a 5alpha-reductase inhibitor that has been used for the treatment of benign prostatic hyperplasia and male-pattern baldness. At doses used clinically, its major effect is through suppression of type 2 5alpha-reductase, because it has a much lower affinity for the type 1 isoenzyme. Finasteride suppresses DHT by about 70% in serum and by as much as 85-90% in the prostate. The remaining DHT in the prostate is likely to be the result of type 1 5alpha-reductase. Suppression of both 5alpha-reductase isoenzymes with GI198745 result in greater and more consistent suppression of serum dihydrotestosterone than that observed with a selective inhibitor of type 2 5alpha-reductase. Physiological and clinical studies comparing dual 5alpha-reductase inhibitors, such as GI198745, with selective type 2, such as finasteride, will be needed to determine the clinical relevance of type 1 5alpha-reductase within the prostate. Two large international multicenter, phase III trials have been published documenting the safety and efficacy of finasteride in the treatment of human benign prostatic hyperplasia. Combining these two studies, randomized, controlled data are available for 12 months. Noncontrolled extension of these data from a subset of patients, who elected to continue drug treatment for 3, 4 or 5 years, are also available. Long-term medical therapy with finasteride can reduce clinically significant endpoints such as acute urinary retention or surgery. According to the meta-analysis of six randomised clinical trial with finasteride, finasteride is most effective in men with large prostates. A more effective dual inhibitor of type 1 and 2 human 5alpha-reductase may lower circulating DHT to a greater extent than finasteride and show advantages in the treatment of human benign prostatic hyperplasia and other disease states that depend on DHT. CONCLUSION: Clinical evaluation of potent dual 5alpha-reductase inhibitors may help define the relative roles of human type 1 and 2 5alpha-reductase in the pathophysiology of benign prostatic hyperplasia and other androgen-dependent diseases.     

Treatment of Symptomatic Benign Prostatic Hyperplasia: Current and Future Clinical Practice in Europe – What is Really Happening?

The management of symptomatic benign prostatic hyperplasia (BPH) has changed significantly over the last decade in response to the availability of new treatment options. Evidence from a large-scale, pan-European study has shown that assessment and treatment allocation for BPH varies significantly within Europe, reflecting local clinical practice preferences, and drug availability and pricing, rather than evidence-based clinical guidelines. There is now evidence from a wide range of epidemiologic and clinical studies to demonstrate that a proportion of men with BPH will have progression of their disease. Such men can be identified through prostate-specific antigen assessment. It has also become apparent that watchful waiting may not always be the optimal approach for all men with mild symptomatic BPH. Data from large-scale clinical studies have demonstrated that treatment with 5α-reductase (5-AR) inhibitors not only significantly ameliorates symptoms of BPH, but also, in contrast to α-blockers, reduces the long-term risks of acute urinary retention and BPH-related surgery. Knowledge of the clinical characteristics that may predict the progression of BPH may thus permit a proactive approach to the management of the disease, whereby men at risk of progression can be identified at an early stage and treated appropriately to reduce their risk of progression. However, it appears that 5-AR inhibitors are often under-prescribed in at-risk men in clinical practice. Therefore, there is a need for a change in clinical practice to reflect the level 1 evidence for 5-AR inhibitors in men with symptomatic BPH who are at risk of disease progression.     

Chronic ischemia alters prostate structure and reactivity in rabbits

PURPOSE: Autopsy studies performed in men older than 80 years old have demonstrated that 90% have histological evidence of benign prostatic hyperplasia. Despite this fact pressure flow studies in men of this age who are referred for the evaluation of lower urinary tract symptoms have shown that only 40% have evidence of bladder outlet obstruction. To our knowledge the specific features of benign prostatic hyperplasia responsible for bladder outlet obstruction are not known. To investigate the possible etiological factors responsible for bladder outlet obstruction we determined whether chronic ischemia alters the structural and functional properties of the prostate. MATERIALS AND METHODS: Male New Zealand White rabbits weighing 3.5 to 4 kg. were divided into a chronic prostate ischemia (12), hypercholesterolemia (8) and age matched control (8) group. The chronic prostate ischemia group underwent balloon endothelial injury of the iliac arteries and received a 0.5% cholesterol diet, the hypercholesterolemia group received a 0.5% cholesterol diet only and controls received a regular diet. After 12 weeks using anesthesia iliac artery and prostatic blood flow was measured by an ultrasonic and laser Doppler flowmeter, respectively. The animals were then sacrificed and the prostate was processed for histological evaluation, immunohistochemical staining for vascular endothelial growth factor expression and organ bath studies. RESULTS: Iliac artery and prostatic blood flow was significantly decreased in the chronic prostate ischemia compared with the hypercholesterolemia and control groups. Histological findings included thickening and fibrosis of the prostatic stroma and cystic atrophy of the epithelium in the chronic prostate ischemia group as well as minor thickening of the stroma in the hypercholesterolemia group. These structural changes correlated with decreased vascular endothelial growth factor expression. Organ bath studies showed that chronic ischemia and to a lesser extent hypercholesterolemia impaired electrical field stimulation induced neurogenic relaxation of the prostatic tissue. Neurogenic relaxation of the prostatic tissue was improved by combined treatment with indomethacin and L-arginine in the hypercholesterolemia but not in the chronic prostate ischemia group. Nitric oxide donor sodium nitroprusside produced comparable relaxation in all 3 groups. CONCLUSIONS: Chronic ischemia causes marked changes in prostatic structure and contractility. Ischemia induced glandular atrophy was consistently associated with decreased vascular endothelial growth factor expression. Decreased relaxation of the ischemic tissue to electrical field stimulation appears to involve the nitric oxide pathway. The nitric oxide precursor L-arginine reversed hypercholesterolemia induced impairment of prostatic tissue relaxation. Our study suggests that chronic ischemia results in thickening and fibrosis of the prostate, changing its mechanical properties. Chronic ischemia also impairs neurogenic relaxation in the prostate. We discuss the possible relationship of these changes to clinical bladder outlet obstruction.     

Benign prostatic hyperplasia progression and its impact on treatment

PURPOSE OF REVIEW: Management of men with benign prostatic hyperplasia should reduce the lifetime risk of acute urinary retention and the need for benign prostatic hyperplasia-related surgery. A number of recent studies demonstrate that 5alpha-reductase inhibitors are unique in providing a long-term combination of improvements in symptoms and flow, and reductions in the risks of acute urinary retention and surgical intervention. RECENT FINDINGS: The 5alpha-reductase inhibitor finasteride was shown to reduce the risk of retention and surgery in men with large prostate volumes and/or high PSA. Recent studies have examined the role of adding an alpha1-blocker to 5alpha-reductase inhibitor in short- or long-term combination. The Medical Therapy of Prostatic Symptoms study randomised 3,047 men with benign prostatic hyperplasia to treatment with a 5alpha-reductase inhibitor (finasteride), an alpha1 blocker (doxazosin), a combination of both, or placebo. Only treatment arms containing 5alpha-reductase inhibitor therapy were associated with longer-term significant reductions in the risk of acute urinary retention and invasive therapy for benign prostatic hyperplasia. Three randomised, two-year, placebo-controlled studies have assessed the clinical relevance of the >93% DHT suppression provided by dutasteride. Dutasteride was also associated with a reduction in the risk of acute urinary retention of 57%, and a reduction of 48% in the risk of surgical intervention compared with placebo after 2 years. SUMMARY: Short-term combination of 5alpha-reductase inhibitor and alpha-blockade are optimal in providing symptomatic improvement among patients who require symptom relief, while enabling the initiation of 5alpha-reductase inhibitor therapy to reduce the risk of subsequent acute urinary retention or benign prostatic hyperplasia-related surgery in men who are at greater risk of disease progression.     

Canine prostatic intraepithelial neoplasia: Is the comparative model relevant?

BACKGROUND: Histologic sections from an archival collection of a veterinary teaching hospital were examined to determine the likelihood of detection of canine high-grade prostatic intraepithelial neoplasms (HGPIN), as a prelude to use of the canine model of prostatic carcinogenesis for chemopreventive strategies. METHODS: Tissue specimens representing clinically healthy (normal) prostate glands, benign prostatic hyperplasia, and prostatic carcinoma were examined in one tissue plane for histological evidence of HGPIN. RESULTS: No histological evidence of HGPIN was detected in 20 normal prostate glands or 95 prostate glands with benign prostatic hyperplasia. Seven of 20 prostatic carcinomas had synchronous HGPIN. CONCLUSIONS: Histological evidence of HGPIN is unlikely to be detected in the healthy or hyperplastic canine prostate gland with the clinically-procured biopsy. This might diminish the usefulness of canine HGPIN in temporal studies of chemoprevention of prostate cancer. HGPIN was found simultaneously with prostatic carcinoma in more than one-third of the carcinomas examined.