Benign prostatic hyperplasia: clinical overview and value of diagnostic imaging

Primary Paraganglioma of the Prostate: A Systematic Review of the Literature for A Rare Entity

BACKGROUND

Paragangliomas of the urinary tract are exceptionally uncommon, and sporadic case reports of primary paraganglioma of the prostate have been reported in the literature.

METHODS

Systematic research in PubMed/Medline and Scopus databases concerning primary prostatic paraganglioma was performed by two independent investigators.

RESULTS

This analysis included 25 adult males, with a mean age of 49.8 ± 22.4 years. 32% of included patients had a history of hypertension. Problems during urination (52%), blood loss (44%), either as hematuria or hemospermia, and catecholamine-related symptoms (36%) comprised the most frequently reported clinical manifestations. Digital rectal examination found a palpable nodule in 36% of patients, while prostatic specific antigen (PSA) was normal in all tested patients. Abdominal ultrasound (44%), computed tomography (44%) and magnetic resonance imaging (28%) helped to identify the primary lesion. 24-hour urine epinephrine, norepinephrine and vanillylmandelic acid (VMA) levels were elevated in 90%, 80% and 90% of included patients. Open surgical excision of the mass was performed in 40%, transurethral resection in 8%, open radical prostatectomy in 24%, transurethral resection of the prostate in 16% and robot-assisted radical prostatectomy in 4% of included patients.

CONCLUSION

Due to atypical clinical manifestation and scarcity of prostatic paraganglioma, urologists should be aware of this extremely rare entity.

Summary Paper on the 2023 European Association of Urology Guidelines on the Management of Non-neurogenic Male Lower Urinary Tract Symptoms

CONTEXT

Lower urinary tract symptoms (LUTS) are common, often bothersome, and have multifactorial aetiology.

OBJECTIVE

To present a summary of the 2023 version of the European Association of Urology guidelines on the management of male LUTS.

EVIDENCE ACQUISITION

A structured literature search from 1966 to 2021 selected the articles with the highest certainty evidence. The Delphi technique consensus approach was used to develop the recommendations.

EVIDENCE SYNTHESIS

The assessment of men with LUTS should be practical. A careful medical history and physical examination are essential. Validated symptom scores, urine test, uroflowmetry, and postvoid urine residual, as well as frequency-volume charts for patients with nocturia or predominately storage symptoms should be used. Prostate-specific antigen should be ordered if a diagnosis of prostate cancer changes the treatment plan. Urodynamics should be performed for selected patients. Men with mild symptoms are candidates for watchful waiting. Behavioural modification should be offered to men with LUTS prior to, or concurrent with, treatment. The choice of medical treatment depends on the assessment findings, predominant type of symptoms, ability of the treatment to change the findings, and the expectations to be met in terms of the speed of onset, efficacy, side effects, and disease progression. Surgery is reserved for men with absolute indications, and for patients who fail or prefer not to receive medical therapy. Surgical management has been divided into five sections: resection, enucleation, vaporisation, and alternative ablative and nonablative techniques. The choice of surgical technique depends on patient's characteristics, expectations, and preferences; surgeon's expertise; and availability of modalities.

CONCLUSIONS

The guidelines provide an evidence-based approach for the management of male LUTS.

PATIENT SUMMARY

A clinical assessment should identify the cause(s) of symptoms and define the clinical profile and patient's expectations. The treatment should aim to ameliorate symptoms and reduce the risk of complications.

Prostate Cancer and Its Mimics-A Pictorial Review

BACKGROUND

Multiparametric prostate MRI (mpMRI) is gaining wider recommendations for diagnosing and following up on prostate cancer. However, despite the high accuracy of mpMRI, false positive and false negative results are reported. Some of these may be related to normal anatomic structures, benign lesions that may mimic cancer, or poor-quality images that hamper interpretation. The aim of this review is to discuss common potential pitfalls in the interpretation of mpMRI.

METHODS

mpMRI of the prostates was performed on 3T MRI scanners (Philips Achieva or Siemens Magnetom Vida) according to European Society of Urogenital Radiology (ESUR) guidelines and technical requirements.

RESULTS

This pictorial review discusses normal anatomical structures such as the anterior fibromuscular stroma, periprostatic venous plexus, central zone, and benign conditions such as benign prostate hyperplasia (BPH), post-biopsy hemorrhage, prostatitis, and abscess that may imitate prostate cancer, as well as the appearance of prostate cancer occurring in these locations. Furthermore, suggestions on how to avoid these pitfalls are provided, and the impact of image quality is also discussed.

CONCLUSIONS

In an era of accelerating prostate mpMRI and high demand for high-quality interpretation of the scans, radiologists should be aware of these potential pitfalls to improve their diagnostic accuracy.

Re-evaluating the diagnostic efficacy of PSA as a referral test to detect clinically significant prostate cancer in contemporary MRI-based image-guided biopsy pathways

Introduction

Modern image-guided biopsy pathways at diagnostic centres have greatly refined the investigations of men referred with suspected prostate cancer. However, the referral criteria from primary care are still based on historical prostate-specific antigen (PSA) cut-offs and age-referenced thresholds. Here, we tested whether better contemporary pathways and biopsy methods had improved the predictive utility value of PSA referral thresholds.

Methods

PSA referral thresholds, age-referenced ranges and PSA density (PSAd) were assessed for positive predictive value (PPV) in detection of clinically significant prostate cancer (csPCa - histological ⩾ Grade Group 2). Data were analysed from men referred to three diagnostics centres who used multi-parametric magnetic resonance imaging (mpMRI)-guided prostate biopsies for disease characterisation. Findings were validated in a separate multicentre cohort. Results: Data from 2767 men were included in this study. The median age, PSA and PSAd were 66.4 years, 7.3 ng/mL and 0.1 ng/mL2, respectively. Biopsy detected csPCa was found in 38.7%. The overall area under the curve (AUC) for PSA was 0.68 which is similar to historical performance. A PSA threshold of ⩾ 3 ng/mL had a PPV of 40.3%, but this was age dependent (PPV: 24.8%, 32.7% and 56.8% in men 50-59 years, 60-69 years and ⩾ 70 years, respectively). Different PSA cut-offs and age-reference ranges failed to demonstrate better performance. PSAd demonstrated improved AUC (0.78 vs 0.68, p < 0.0001) and improved PPV compared to PSA. A PSAd of ⩾ 0.10 had a PPV of 48.2% and similar negative predictive value (NPV) to PSA ⩾ 3 ng/mL and out-performed PSA age-reference ranges. This improved performance was recapitulated in a separate multi-centre cohort (n = 541).

Conclusion

The introduction of MRI-based image-guided biopsy pathways does not appear to have altered PSA diagnostic test characteristics to positively detect csPCa. We find no added value to PSA age-referenced ranges, while PSAd offers better PPV and the potential for a single clinically useful threshold (⩾0.10) for all age groups.

Level of evidence

IV.

Contemporary Review of Multimodality Imaging of the Prostate Gland

Tissue changes and the enlargement of the prostate, whether benign or malignant, are among the most common groups of diseases that affect men and can have significant impacts on length and quality of life. The prevalence of benign prostatic hyperplasia (BPH) increases significantly with age and affects nearly all men as they grow older. Other than skin cancers, prostate cancer is the most common cancer among men in the United States. Imaging is an essential component in the diagnosis and management of these conditions. Multiple modalities are available for prostate imaging, including several novel imaging modalities that have changed the landscape of prostate imaging in recent years. This review will cover the data relating to commonly used standard-of-care prostate imaging modalities, advances in newer technologies, and newer standards that impact prostate gland imaging.

Semi-Automatic MRI Feature Assessment in Small- and Medium-Volume Benign Prostatic Hyperplasia after Prostatic Artery Embolization

(1) Background: To assess the treatment response of benign prostatic syndrome (BPS) following prostatic artery embolization (PAE) using a semi-automatic software analysis of magnetic resonance imaging (MRI) features and clinical indexes. (2) Methods: Prospective, monocenter study of MRI and clinical data of n = 27 patients with symptomatic BPS before and (1, 6, 12 months) after PAE. MRI analysis was performed using a dedicated semi-automatic software for segmentation of the central and the total gland (CG, TG), respectively; signal intensities (SIs) of T1-weighted (T1w), T2-weighted (T2w), and diffusion-weighted images (DWI), as well as intravesical prostatic protrusion (IPP) and prostatic volumes (CGV, TGV), were evaluated at each time point. The semi-automatic assessed TGV was compared to conventional TGV by an ellipse formula. International prostate symptom score (IPSS) and international consultation on incontinence questionnaire−urinary incontinence short form (ICIQ-UI SF) questionnaires were used as clinical indexes. Statistical testing in the form of ANOVA, pairwise comparisons using Bonferroni correction, and multiple linear correlations, were conducted using SPSS. (3) Results: TGV was significantly reduced one, six, and 12 months after PAE as assessed by the semi-automatic approach and conventional ellipse formula (p = 0.005; p = 0.025). CGV significantly decreased after one month (p = 0.038), but showed no significant differences six and 12 months after PAE (p = 0.191; p = 0.283). IPP at baseline was demonstrated by 25/27 patients (92.6%) with a significant decrease one, six, and 12 months after treatment (p = 0.028; p = 0.010; p = 0.008). Significant improvement in IPSS and ICIQ-UI SF (p = 0.002; p = 0.016) after one month correlated moderately with TGV reduction (p = 0.031; p = 0.05, correlation coefficients 0.52; 0.69). Apparent diffusion coefficient (ADC) values of CG significantly decreased one month after embolization (p < 0.001), while there were no significant differences in T1w and T2w SIs before and after treatment at each time point. (4) Conclusions: The semi-automatic approach is appropriate for the assessment of volumetric and morphological changes in prostate MRI following PAE, able to identify significantly different ADC values post-treatment without the need for manual identification of infarct areas. Semi-automatic measured TGV reduction is significant and comparable to the TGV calculated by the conventional ellipse formula, confirming the clinical response after PAE.

Tissue stiffness in BPH patients from magnetic resonance elastography

Background

BPH is commonly found in older men which can lead to lower urinary tract symptoms. Magnetic resonance elastography (MRE) is an innovative, noninvasive imaging technique used to evaluate tissue stiffness. There has not been any study, however, that assessed the tissue stiffness in patients with BPH. A prospective descriptive study was performed to demonstrated MRI and MRE techniques of the prostate gland in ten patients with BPH to assess tissue stiffness, features of BPH on MRI and components of BPH in the area of increased stiffness.

Results

MRI and MRE examinations in all patients were successful without any complications. The mean tissue stiffness of the whole prostate gland was 4.40 ± 0.71 kPa with good reproducibility (ICC 0.82). Stromal components and mixed glandular-stromal components tended to be associated with the areas of increased stiffness on stiffness images, 50.6% for stromal components and 37.9% for mixed glandular-stromal components. Some MRI findings were seen on the patients with high mean stiffness values such as prostatic calcification, type-5 BPH pattern and large prostate volumes.

Conclusions

Prostate MRE is a useful noninvasive reproducible diagnostic tool for evaluating prostate tissue stiffness by both qualitative and quantitative assessments. The mean prostate tissue stiffness from MRE in patients with BPH in this study was 4.40 ± 0.71 kPa. Some MRI features might be associated with increased tissue stiffness.

Trial registration: PID 229. Registered 4 October 2019. http://md.redcap.kku.ac.th

Success of endoscopic prostatic surgery in patients with DUA: a prospective observational and analytic study

Introduction:

Detrusor underactivity (DUA) is a highly prevalent and poorly understood disease in urology practice. Conservative treatment in the form of clean intermittent catheterization (CIC) and pharmacotherapy are in use for DUA without good results. Endoscopic prostate surgery was initially considered ineffective in such patients. But a recent series of retrospective studies showed promising results of surgery in DUA. Therefore, we conducted this prospective study to evaluate success of endoscopic prostatic surgery in a patient with DUA.

Materials and methods:

This is prospective observational study of 50 patients, satisfying the inclusion criteria, at Ruby Hall Clinic, Pune, conducted between March 2017 and March 2019. Inclusion criteria are that the patients are male, aged > 50 years; urodynamically diagnosed with DUA; a bladder contractility index < 90 with associated bladder outlet obstruction index (BOOI) between 20–40 (equivocal) or > 40 (obstruction), who presented with lower urinary tract symptoms and poor flow ( Qmax < 10 ml/s in a voided volume of >150 ml. Patients were excluded from the study if they had DUA due to neurological causes or spinal trauma, an acontractile detrusor, and were < 50 years.

Results:

The follow-up period for each patient was 12 months. The mean international prostate specific score reduced from 24.82 ± 2.74 preoperatively to 4.4 ± 1.85 postoperatively. Mean quality of life score reduced from 4.06 ± 0.68 to 0.82 ± 0.62. Mean Qmax increased from 6.26 ±1.46 ml/s to 12.22 ±1.6 ml/s. Mean post-void residual urine volume reduced form 241.9 ±74.9 to 77.3 ±20.75. All of these were statistically significant with a p value < 0.00001.

Conclusion:

Transurethral resection of the prostate (monopolar/laser) to reduce BOO should be considered as an alternative, viable treatment option in men with DUA. Preoperative counselling and postoperative follow-up are crucial in the management of such patients. Level of evidence:

Eight Days of Water-Only Fasting Promotes Favorable Changes in the Functioning of the Urogenital System of Middle-Aged Healthy Men

The aim of this study was to determine whether, after 8 days of water-only fasting, there are changes in the efficiency of the lower urinary tract, the concentration of sex hormones, and the symptoms of prostate diseases in a group of middle-aged men (n = 14). For this purpose, before and after 8 days of water-only fasting (subjects drank ad libitum moderately mineralized water), and the following somatic and blood concentration measurements were made: total prostate specific antigen (PSA-T), free prostate specific antigen (PSA-F), follicle stimulating hormone (FSH), luteotropic hormone (LH), prolactin (Pr), total testosterone (T-T), free testosterone (T-F), dehydroepiandrosterone (DHEA), sex hormone globulin binding (SHGB), total cholesterol (Ch-T), β-hydroxybutyrate (β-HB). In addition, prostate volume (PV), volume of each testis (TV), total volume of both testes (TTV), maximal urinary flow rate (Qmax), and International Prostate Symptom Score (IPSS) values were determined. The results showed that after 8 days of water-only fasting, Qmax and IPSS improved but PV and TTV decreased significantly. There was also a decrease in blood levels of PSA-T, FSH, P, T-T, T-F, and DHEA, but SHGB concentration increased significantly. These results indicate that 8 days of water-only fasting improved lower urinary tract functions without negative health effects.

What You Need to Know Before Reading Multiparametric MRI for Prostate Cancer

OBJECTIVE. Multiparametric MRI (mpMRI) has become the main imaging modality for the detection, localization, and local staging of prostate cancer over the past decade. For radiologists to achieve consistent and reproducible reporting of prostate mpMRI, a comprehensive evaluation of the gland including detailed knowledge of anatomy, pathology, and clinical data is required. This article familiarizes radiologists with common pitfalls and conditions that affect mpMRI performance during readouts. CONCLUSION. Consistent, accurate, and reproducible reporting of prostate mpMRI is vital. Additionally, radiologists should be aware of common diagnostic pitfalls that can hinder mpMRI performance.

Prostate Benign Diseases

Magnetic resonance imaging (MRI) has been increasingly used in the detection, localization, and staging of prostate cancer. Because of its excellent soft tissue contrast and multiplane imaging, it can be also very useful in the evaluation of benign prostate diseases. Prostatic benign disorders have a high prevalence, vastly represented by benign prostatic hyperplasia and prostatitis. On the contrary, benign prostatic neoplasms are extremely rare, represented by multilocular cystadenoma, leiomyomas, hemangioma, and granular cell tumor, although these uncommon tumors have been most encountered due to widespread use of MRI. Congenital prostatic anomalies are associated with defects in the development of the prostate embryology, including hypoplasia, ectopia, and vascular malformations, abnormalities rarely seen on cross-sectional imaging. Prostatic cysts are the most common development abnormalities and occasionally are related to clinical symptoms, mainly due to infection and hemorrhage. As with prostate cancer, multiparametric MRI is a reliable tool for the diagnosis and management of benign prostatic diseases as well, providing additional information such morphological changes of the prostate, more accurate prostatic measurements, and functional characteristics of nonmalignant prostatic lesions. In this review, we discuss MRI findings of these benign prostatic diseases.

Endothelial dysfunction, abnormal vascular structure and lower urinary tract symptoms in men and women

BACKGROUND

Lower urinary tract symptoms (LUTS) is not only common symptoms in elderly men and women but also risk of future cardiovascular events. The purpose of this study was to evaluate the relationships of vascular function and structure with LUTS in men and women.

METHODS

We investigated flow-mediated vasodilation (FMD) and nitroglycerine-induced vasodilation (NID) as vascular function, brachial-ankle pulse wave velocity (baPWV) as vascular structure, and LUTS assessed by International Prostate Symptom Score (IPSS) in 287 men and 147 women.

RESULTS

IPSS was significantly correlated with traditional cardiovascular risk factors, Framingham risk score, FMD, NID and baPWV. Moderate to severe LUTS was associated with the prevalence of coronary heart disease in men but not in women. In men, FMD and NID were significantly lower in the moderate to severe LUTS group than in the none to mild LUTS group (2.1 ± 2.0% vs. 4.0 ± 3.0% and 9.3 ± 6.1% vs. 12.8 ± 6.6%, P < 0.001, respectively). baPWV was significantly higher in the moderate to severe LUTS group than in the none to mild LUTS group (1722 ± 386 cm/s vs. 1509 ± 309 cm/s, P < 0.001). In multivariate analysis, FMD was independently associated with a decrease in the odds ratio of moderate to severe LUTS in men (OR: 0.83, 95% CI, 0.72-0.95; P = 0.008) but not in women. NID and baPWV were not independently associated with moderate to severe LUTS either in men or women.

CONCLUSIONS

These findings suggest that endothelial dysfunction is associated with LUTS in men. LUTS in men may be useful for a predictor of cardiovascular events.

CLINICAL TRIAL REGISTRATION INFORMATION

URL for Clinical Trial: http://UMIN; Registration Number for Clinical Trial: UMIN000003409.

[How to evaluate BPH-related SBAUs in clinical practice and research?]

OBJECTIVE

To describe the useful explorations in the clinical evaluation of the symptoms of the lower urinary tract symptoms possibly related to BPH (LUTS/BPH), and to list the information necessary to allow an evaluation of an instrumental or surgical intervention in the treatment of the hypertrophy and benign prostatic obstruction.

METHOD

Bibliographic research in English using the European, American and French recommendations on the evaluation of BPH, supplemented by a Pubmed search.

RESULTS AND CONCLUSIONS

A number of systematic investigations into the evaluation of a man with LUTS/BPH include interrogation, clinical examination with rectal examination, urinalysis, flowmeter and post-micturition residual volume. The voiding catalog is necessary to understand the mechanism of a nocturia. PSA has a triple potential of interest: evaluation of the risk of progression, evaluation of the prostatic volume and diagnosis of a cancer of the prostate. Creatinine is needed only when chronic retention is observed and before surgery. Urethrocystoscopy is essential in case of hematuria, suspicion of stenosis of the urethra or bladder tumor. Ultrasound for evaluation of prostate volume is essential before surgery, and may be helpful in guiding the decision to prescribe a 5 alpha reductase inhibitor. No non-invasive technique has proven its possible substitution for pressure flow studies when indicated. When a researcher is considering evaluating a surgical or instrumental treatment for BPH, preoperative, perioperative and follow-up parameters are expected from readers to get a fair idea of the technique being evaluated. LEVEL OF EVIDENCE 5: Consensus d'experts.

Predictors of the international prostate symptoms scores for patients with lower urinary tract symptoms: A descriptive cross-sectional study

Background

Lower urinary tract symptoms (LUTSs) can significantly reduce men's quality of life and may point to serious pathology of the urogenital tract. This study aimed at finding predictors of symptoms score on the International Prostate Symptom Score (IPSS) for patients with LUTS.

Materials and Methods

The study was cross-sectional conducted among 225 Ghanaian men visiting the urology clinic at Komfo Anokye Teaching Hospital. Trained interviewers used the IPSS, which adds a quality of life question to the American Urology Association symptom index to determine the extent to which patients are troubled by their symptoms. Five milliliters of blood was collected for total prostate-specific antigen (PSA) measurement. Transrectal ultrasonography was performed to evaluate the prostate volume (PV).

Results

The mean age of the participants was 67.96 ± 14.57. The average score obtained from the study participants using the IPSS scale was 17.52 ± 7.83. There was a significant association between bother score and IPSS symptoms grade (P < 0.0001). Regression plot of the participants' points for IPSS in relation to the age, PSA, and PV showed statistically significant positive associations (P < 0.05). However, the coefficients of determination (R²) were 0.156, 0.022, and 0.048, respectively. This means that each unit increase of age, PSA, and PV only influences 15.6%, 2.3%, and 4.8% of the change in the symptom score. There was statistically significant association between age and moderate-to-severe LUTS with age range of 75 years above recording the highest odds (adjusted odds ratio (AOR) = 18.72, (1.15-99.78), P < 0.0001). The PSA range 20.1-50 ng/ml was significantly associated with moderate-to-severe LUTS (AOR = 17.37 (2.19-223.45), P = 0.006). Moreover, other factors, which were significantly associated with moderate-to-severe LUTS, were smoking (AOR = 0.32 (0.11-0.94) P = 0.038) and being widowed (AOR = 0.05 (0.002-0.52), P =0.010) respectively.

Conclusion

The study found a statistically significant correlation between age, PSA, PV, and IPSS scores; however, these influences were mild.

MRI features after prostatic artery embolization for the treatment of medium- and large-volume benign hyperplasia

PURPOSE

To assess magnetic resonance imaging (MRI) features after prostatic artery embolization (PAE) for the treatment of medium- and large-volume benign prostatic hyperplasia and to correlate prostate volume with clinical indexes.

METHODS

We retrospectively evaluated 28 patients who underwent PAE. MRI examinations of the prostate were performed to evaluate signal intensity changes and the characteristics of infarcted areas. Prostate volume and the apparent diffusion coefficient (ADC) were measured at an average of 10 days post-PAE and at 1, 3, 6, and 12 months post-PAE. Some clinical indexes were evaluated before and 12 months after PAE. The paired t test, ANOVA, and multiple linear correlation analyses were performed by using the statistical software, SPSS.

RESULTS

All patients experienced prostatic infarction. The prostate volume decreased continuously (p < 0.05). The ADC values before and after 1, 3, 6, or 12 months of embolization (b = 1000 and 2000 s/mm²) were statistically significantly different. The ADC values (b = 3000 s/mm²) were also statistically significantly different before and at each interval time after embolization (p < 0.05). Prostate volume changes correlated significantly with patient age and post-void residual urine volume (p < 0.05).

CONCLUSIONS

MRI can be used for assessing changes in signal intensity and ADC values of infarction as well as the volume of the prostate after PAE. After PAE, ultrahigh b value diffusion-weighted imaging (DWI) can show early infarction better than lower b value DWI.

Magnetic Resonance Imaging and Molecular Characterization of a Hormone-Mediated Murine Model of Prostate Enlargement and Bladder Outlet Obstruction

Urinary complications resulting from benign prostatic hyperplasia and bladder outlet obstruction continue to be a serious health problem. Novel animal model systems and imaging approaches are needed to understand the mechanisms of disease initiation, and to develop novel therapies for benign prostatic hyperplasia. Long-term administration of both estradiol and testosterone in mice can result in prostatic enlargement and recapitulate several clinical components of lower urinary tract symptoms. Herein, we use longitudinal magnetic resonance imaging and histological analyses to quantify changes in prostatic volume, urethral volume, and genitourinary vascularization over time in response to estradiol-induced prostatic enlargement. Our data demonstrate significant prostatic enlargement by 12 weeks after treatment, with no detectable immune infiltration by macrophages or T- or B-cell populations. Importantly, the percentage of cell death, as measured by terminal deoxynucleotidyl transferase dUTP nick-end labeling, was significantly decreased in the prostatic epithelium of treated animals as compared to controls. We found no significant change in prostate cell proliferation in treated mice when compared to controls. These studies highlight the utility of magnetic resonance imaging to quantify changes in prostatic and urethral volumes over time. In conjunction with histological analyses, this approach has the high potential to enable mechanistic studies of initiation and progression of clinically relevant lower urinary tract symptoms. In addition, this model is tractable for investigation and testing of therapeutic interventions to ameliorate or potentially reverse prostatic enlargement.

Targeting phenotypic heterogeneity in benign prostatic hyperplasia

Benign prostatic hyperplasia and associated lower urinary tract symptoms remain difficult to treat medically, resulting in hundreds of thousands of surgeries performed annually in elderly males. New therapies have not improved clinical outcomes since alpha blockers and 5 alpha reductase inhibitors were introduced in the 1990s. An underappreciated confounder to identifying novel targets is pathological heterogeneity. Individual patients display unique phenotypes, composed of distinct cell types. We have yet to develop a cellular or molecular understanding of these unique phenotypes, which has led to failure in developing targeted therapies for personalized medicine. This review covers the strategic experimental approach to unraveling the cellular pathogenesis of discrete BPH phenotypes and discusses how to incorporate these findings into the clinic to improve outcomes.

Magnetic resonance imaging of benign prostatic hyperplasia

Benign prostatic hyperplasia (BPH) is a common condition in middle-aged and older men and negatively affects the quality of life. An ultrasound classification for BPH based on a previous pathologic classification was reported, and the types of BPH were classified according to different enlargement locations in the prostate. Afterwards, this classification was demonstrated using magnetic resonance imaging (MRI). The classification of BPH is important, as patients with different types of BPH can have different symptoms and treatment options. BPH types on MRI are as follows: type 0, an equal to or less than 25 cm3 prostate showing little or no zonal enlargements; type 1, bilateral transition zone (TZ) enlargement; type 2, retrourethral enlargement; type 3, bilateral TZ and retrourethral enlargement; type 4, pedunculated enlargement; type 5, pedunculated with bilateral TZ and/or retrourethral enlargement; type 6, subtrigonal or ectopic enlargement; type 7, other combinations of enlargements. We retrospectively evaluated MRI images of BPH patients who were histologically diagnosed and presented the different types of BPH on MRI. MRI, with its advantage of multiplanar imaging and superior soft tissue contrast resolution, can be used in BPH patients for differentiation of BPH from prostate cancer, estimation of zonal and entire prostatic volumes, determination of the stromal/glandular ratio, detection of the enlargement locations, and classification of BPH types which may be potentially helpful in choosing the optimal treatment.

MRI evaluation of benign prostatic hyperplasia: Correlation with international prostate symptom score

PURPOSE

To investigate the correlation between magnetic resonance imaging (MRI)-derived prostate parameters and benign prostatic hyperplasia (BPH) type with the International Prostate Symptom Score (IPSS).

MATERIALS AND METHODS

In all, 61 patients (median age, 60; range, 41-81 years) who underwent preoperative MRI and prostatectomy were included in this retrospective study. The MRI-based parameters including total prostate volume (TPV), transition zone (TZ) volume (TZV), TZ index, intravesical prostatic protrusion (IPP), the anterior fibromuscular stroma (AFMS) distance, prostatic urethral angle, bladder wall thickness, urethral wall thickness, urethral compression, urethral wall changes, and BPH type were correlated with total IPSS, IPSS-storage symptom (IPSS-ss), IPSS-voiding symptom (IPSS-vs), and responses to the individual IPSS questions using Spearman (ρ) or Pearson (r) correlation coefficients, one-way analysis of variance (ANOVA), and multiple linear regression.

RESULTS

TPV (r = 0.414, P = 0.001), TZV (r = 0.405, P = 0.001), IPP (r = 0.270, P = 0.04), and AFMS distance (r = 0.363, P = 0.004) correlated with total IPSS. In multiple linear regression analysis, TZV was the only predictor for total IPSS (P = 0.001), IPSS-ss (P < 0.001), IPSS-vs (P = 0.03), and the scores for the IPSS questions 1 (P = 0.03) and 4 (P = 0.001). TPV was a predictor of the scores for questions 2 (P = 0.003), 3 (P = 0.009), and 7 (P < 0.001).

CONCLUSION

Several MRI-derived prostate measurements (TPV, TZV, IPP, AFMS distance) correlated with total IPSS. TZV was the only predictor for total IPSS based on multiple regression analysis.

LEVEL OF EVIDENCE

3 J. Magn. Reson. Imaging 2017;45:917-925.

Role of multiparametric MRI in the diagnosis of prostate cancer: update

Prostate cancer is the most common malignancy of the male gender. The role of magnetic resonance imaging has evolved very rapidly over the years to be currently recognized as a fundamental tool in the diagnosis, treatment and follow-up of prostate cancer.

Benign Conditions That Mimic Prostate Carcinoma: MR Imaging Features with Histopathologic Correlation

Multiparametric magnetic resonance (MR) imaging combines anatomic and functional imaging techniques for evaluating the prostate and is increasingly being used in diagnosis and management of prostate cancer. A wide spectrum of anatomic and pathologic processes in the prostate may masquerade as prostate cancer, complicating the imaging interpretation. The histopathologic and imaging findings of these potential mimics are reviewed. These entities include the anterior fibromuscular stroma, surgical capsule, central zone, periprostatic vein, periprostatic lymph nodes, benign prostatic hyperplasia (BPH), atrophy, necrosis, calcification, hemorrhage, and prostatitis. An understanding of the prostate zonal anatomy is helpful in distinguishing the anatomic entities from prostate cancer. The anterior fibromuscular stroma, surgical capsule, and central zone are characteristic anatomic features of the prostate with associated low T2 signal intensity due to dense fibromuscular tissue or complex crowded glandular tissue. BPH, atrophy, necrosis, calcification, and hemorrhage all have characteristic features with one or more individual multiparametric MR imaging modalities. Prostatitis constitutes a heterogeneous group of infective and inflammatory conditions including acute and chronic bacterial prostatitis, infective and noninfective granulomatous prostatitis, and malacoplakia. These entities are associated with variable clinical manifestations and are characterized by the histologic hallmark of marked inflammatory cellular infiltration. In some cases, these entities are indistinguishable from prostate cancer at multiparametric MR imaging and may even exhibit extraprostatic extension and lymphadenopathy, mimicking locally advanced prostate cancer. It is important for the radiologists interpreting prostate MR images to be aware of these pitfalls for accurate interpretation. Online supplemental material is available for this article.

The Diagnosis of Benign Prostatic Obstruction: Validation of the Young Academic Urologist Clinical Nomogram

OBJECTIVE

To externally validate the Young Academic Urologist (YAU) nomogram for the prediction of benign prostatic obstruction (BPO) in patients with lower urinary tract symptoms and benign prostatic enlargement.

MATERIALS AND METHODS

Between January 2013 and September 2014, a consecutive series of patients with lower urinary tract symptoms and benign prostatic enlargement underwent standardized pressure flow studies (PFSs) in 2 tertiary Italian centers. Variables assessed were International Prostatic Symptom Score, Prostate Specific Antigen (PSA), prostate size, transitional zone volume, maximal urinary flow rate (Qmax), postvoid residual urine. BPO was defined as a Schäfer grade ≥ 3 at PFSs. Qmax and transitional zone volume were plotted on the YAU nomogram to predict the presence of BPO. Receiver operating characteristic curve analysis was used to evaluate predictive properties of the nomogram for the final diagnosis of BPO.

RESULTS

A total of 449 patients were consecutively enrolled. In those, 310 patients (69%) presented a BPO (Schäfer ≥ 3) at PFSs. The novel YAU nomogram presented an area under the curve of 0.76; 95% confidence interval: 0.72-0.82 for the diagnosis of BPO. At the best cutoff value of 80% (nomogram probability), the sensitivity was 74% and specificity was 79%, the positive predictive value was 89%, and the negative predictive value was 56%.

CONCLUSION

Although further studies are needed to confirm our results, the YAU nomogram was, in our experience, an excellent tool to predict the presence of BPO.

EAU Guidelines on the Assessment of Non-neurogenic Male Lower Urinary Tract Symptoms including Benign Prostatic Obstruction

CONTEXT

Lower urinary tract symptoms (LUTS) represent one of the most common clinical complaints in adult men and have multifactorial aetiology.

OBJECTIVE

To develop European Association of Urology (EAU) guidelines on the assessment of men with non-neurogenic LUTS.

EVIDENCE ACQUISITION

A structured literature search on the assessment of non-neurogenic male LUTS was conducted. Articles with the highest available level of evidence were selected. The Delphi technique consensus approach was used to develop the recommendations.

EVIDENCE SYNTHESIS

As a routine part of the initial assessment of male LUTS, a medical history must be taken, a validated symptom score questionnaire with quality-of-life question(s) should be completed, a physical examination including digital rectal examination should be performed, urinalysis must be ordered, post-void residual urine (PVR) should be measured, and uroflowmetry may be performed. Micturition frequency-volume charts or bladder diaries should be used to assess male LUTS with a prominent storage component or nocturia. Prostate-specific antigen (PSA) should be measured only if a diagnosis of prostate cancer will change the management or if PSA can assist in decision-making for patients at risk of symptom progression and complications. Renal function must be assessed if renal impairment is suspected from the history and clinical examination, if the patient has hydronephrosis, or when considering surgical treatment for male LUTS. Uroflowmetry should be performed before any treatment. Imaging of the upper urinary tract in men with LUTS should be performed in patients with large PVR, haematuria, or a history of urolithiasis. Imaging of the prostate should be performed if this assists in choosing the appropriate drug and when considering surgical treatment. Urethrocystoscopy should only be performed in men with LUTS to exclude suspected bladder or urethral pathology and/or before minimally invasive/surgical therapies if the findings may change treatment. Pressure-flow studies should be performed only in individual patients for specific indications before surgery or when evaluation of the pathophysiology underlying LUTS is warranted.

CONCLUSIONS

These guidelines provide evidence-based practical guidance for assessment of non-neurogenic male LUTS. An extended version is available online (www.uroweb.org/guidelines).

PATIENT SUMMARY

This article presents a short version of European Association of Urology guidelines for non-neurogenic male lower urinary tract symptoms (LUTS). The recommended tests should be able to distinguish between uncomplicated male LUTS and possible differential diagnoses and to evaluate baseline parameters for treatment. The guidelines also define the clinical profile of patients to provide the best evidence-based care. An algorithm was developed to guide physicians in using appropriate diagnostic tests.

Predicting the resected tissue weight from a digital rectal examination and total prostate specific antigen level before transurethral resection of the prostate

OBJECTIVE

To determine the use of the prostate specific antigen (PSA) level and digital rectal examination (DRE) findings to estimate the resected tissue weight (RTW) before transurethral resection of the prostate (TURP).

PATIENTS AND METHODS

We retrospectively analysed 983 patients who underwent TURP between December 2006 and December 2012. The primary outcome was the RTW required for clinical improvement, and was not associated with re-intervention. Age, PSA level, body mass index (BMI) and DRE findings were correlated and modelled with the RTW. The DRE result was defined as DREa (small vs. large) or DREb (small vs. moderate vs. large) according to the surgeon's report. Equations to calculate RTW were developed and tested using receiver operating characteristic (ROC) curve analyses.

RESULTS

There were significant correlations between PSA level (r = 0.4, P < 0.001) and RTW, whilst BMI and age showed weak correlations. The median (range) RTW was 45 (7-60) vs. 15 (6-60) g for small vs. large prostates (DREa) (P < 0.001), respectively. Similarly, the median (range) RTW was 11 (6-59) vs. 26.2 (6-60) vs. 42 (7-60) g in small vs. moderate vs. large prostates (DREb) (P < 0.001), respectively. Using PSA level and DREb (model 3) there was a significantly better ability to estimate RTW than using PSA and DREa (model 2) or PSA alone (model 1) based on ROC curve analyses. The equation developed by model 3 (RTW = 1.2 + (1.13 × PSA) + (DREb × 9.5)) had a sensitivity and specificity of 82% and 71% for estimating a RTW of >30 g, and 84% and 63% for estimating a RTW of >40 g, respectively.

CONCLUSIONS

The PSA level and DRE findings can be used to predict the RTW before TURP.

MRI findings after prostatic artery embolization for treatment of benign hyperplasia

OBJECTIVE

The purpose of this article is to assess and describe the MRI findings after prostatic artery embolization for treatment of benign prostatic hyperplasia.

MATERIALS AND METHODS

We retrospectively evaluated 17 patients who underwent prostatic artery embolization as part of different prospective studies to evaluate this alternative treatment of benign prostatic hyperplasia. Clinical results were evaluated by assessment of urinary catheterization and International Prostate Symptom Score (IPSS). Serial MRI examinations were performed, and the prostatic central gland and peripheral zone were evaluated for signal intensity changes and the presence and characteristics of infarcted areas. Statistical analysis was performed with ANOVA for repeated measures and Student t test.

RESULTS

All patients had clinical success, as defined by the removal of indwelling urinary catheter or decreased IPSS after embolization. Infarcts were seen in 70.6% of the subjects, exclusively in the central gland, were almost always characterized by hyperintensity on T1-weighted images and predominant hypointensity on T2-weighted images, and became smaller (mean reduction, p < 0.001) and isointense to the remaining of the central gland over time. Volume reduction of the prostate after embolization was significant (averaging 32.0% after 12-18 months; p < 0.001) only in patients with infarcts. No statistically significant association was seen between the development of infarcts and IPSS.

CONCLUSION

MRI can be used for assessing the development of infarcts and volume reduction in the prostate after embolization. Further studies are needed to correlate these findings to clinical outcome.

Prostatic stromal neoplasms: differential diagnosis of cystic and solid prostatic and periprostatic masses

OBJECTIVE

The objectives of this article are to illustrate the radiologic-pathologic correlation of prostate stromal neoplasms and to review the imaging appearances of cystic and solid prostatic and periprostatic masses that may mimic prostatic stromal neoplasms.

CONCLUSION

The differential diagnosis for cystic and solid masses in the prostate is broad, and masses arising from periprostatic structures may mimic the appearance of primary prostatic diseases. Attention to clinical and imaging features is helpful in narrowing the differential diagnosis.

120 W Greenlight HPS Laser Photoselective Vaporization of the Prostate for Treatment of Benign Prostatic Hyperplasia in Men with Detrusor Underactivity

Purpose

Most men with benign prostatic hyperplasia (BPH) have bothersome lower urinary tract symptoms (LUTS). This study aimed to investigate the safety and efficacy of high-performance system (HPS) laser photoselective vaporization of the prostate (PVP) for the treatment of BPH in men with detrusor underactivity (DU).

Materials and Methods

From March 2009, 371 patients with BPH were divided into 2 groups according to the findings of preoperative urodynamic study: 239 (64.4%) patients with bladder outlet obstruction (BOO) and 132 (35.6%) patients with bladder outlet obstruction with detrusor underactivity (BOO+DU). 120 W HPS laser PVP was performed to resolve the BOO. The perioperative data and postoperative results at 1 month and 12 months, including the International Prostate Symptom Score (IPSS), maximum urinary flow (Qmax), and postvoid residual urine (PVR) values, were evaluated.

Results

Compared with the preoperative parameters, significant improvements in IPSS, Qmax, and PVR were observed in each group at 1 and 12 months after the operation. In addition, IPSS, Qmax, and PVR were not significantly different between the BOO and BOO+DU groups at 1 and 12 months after the operation.

Conclusions

Surgery to relieve BOO in the patients with BPH seems to be an appropriate treatment modality regardless of the existence of DU.

Multi-parametric MR imaging of transition zone prostate cancer: Imaging features, detection and staging

Magnetic resonance (MR) imaging has been increasingly used in the evaluation of prostate cancer. As studies have suggested that the majority of cancers arise from the peripheral zone (PZ), MR imaging has focused on the PZ of the prostate gland thus far. However, a considerable number of cancers (up to 30%) originate in the transition zone (TZ), substantially contributing to morbidity and mortality. Therefore, research is needed on the TZ of the prostate gland. Recently, MR imaging and advanced MR techniques have been gaining acceptance in evaluation of the TZ. In this article, the MR imaging features of TZ prostate cancers, the role of MR imaging in TZ cancer detection and staging, and recent advanced MR techniques will be discussed in light of the literature.

High spectral and spatial resolution MRI of age-related changes in murine prostate

The purpose of this work was to evaluate high-resolution echo-planar spectroscopic MRI of normal and precancerous prostatic changes in a transgenic mouse line. Simian virus large T-antigen transgenic male mice (N = 7, age = 34 +/- 3.7 weeks) with prostatic hyperplasia and intraepithelial neoplasia (PIN) were studied. High spectral and spatial resolution (HiSS) MRI of the water proton signal was compared to the free induction decay (FID) integral image and conventional gradient-echo and spin-echo imaging. Water peak-height images of the prostate produced from HiSS datasets showed improved contrast-to-noise ratio (CNR) (P < 0.03), and greater morphological detail (P < 0.004) based on texture analysis. Despite the high spectral resolution of the HiSS datasets, signal-to-noise ratio (SNR) compared favorably with that of the FID integral and conventional images. Lobular features in HiSS images of older mice were consistent with hyperplasia seen on histology. A partially deuterated water-filled catheter was inserted in the mouse rectum for susceptibility matching between the colon interior and exterior to minimize image artifacts. These preliminary results suggest that HiSS MRI provides detailed morphology of the murine prostate and can detect early changes associated with the development of cancer. HiSS MRI of patients may have similar advantages.

Transrectal ultrasound versus magnetic resonance imaging in the estimation of prostate volume as compared with radical prostatectomy specimens

INTRODUCTION

There are relatively few studies that compare the use of transrectal ultrasound (TRUS) to magnetic resonance imaging (MRI) to estimate the prostate volume. In this study, we compared the prostate volumes measured with MRI and TRUS with a surgical specimen volume.

PATIENTS AND METHODS

Seventy-three patients underwent TRUS examination of the prostate prior to radical prostatectomy. All specimens were weighed and measured when freshly excised. The corresponding volume measurements calculated using TRUS and MRI were compared retrospectively with the measured volumes of freshly excised prostate.

RESULTS

The volume measured with TRUS and MRI was linearly related to the radical prostatectomy volume. The estimated increase in the prostate volumes measured with TRUS and MRI per specimen volume was 0.9508 and 0.9331 by regression analysis, respectively. If the prostate volumes were <35 cm(3), the prostate volumes measured with MRI overestimated the specimen volumes. If the prostate volumes were >35 cm(3), the prostate volumes measured with MRI underestimated the specimen volumes. The classic ellipsoid formula was adequate for determining the prostate volume.

CONCLUSIONS

In this study, MRI and TRUS gave different volumes. MRI is more accurate than TRUS for determining the prostate volume. However, because TRUS is inexpensive, noninvasive, and almost as accurate as MRI, it should be the preferred method for measuring the prostate volume.

From the archives of the AFIP: Inflammatory and nonneoplastic bladder masses: radiologic-pathologic correlation

Although the vast majority of bladder tumors are epithelial neoplasms, a variety of nonneoplastic disorders can cause either focal bladder masses or diffuse mural thickening and mimic malignancy. Some of these entities are rare and poorly understood such as inflammatory pseudotumor, which produces ulcerated, bleeding polypoid bladder masses. These masses may be large and have an extravesical component. Bladder endometriosis manifests as submucosal masses with characteristic magnetic resonance imaging features consisting of hemorrhagic foci and reactive fibrosis. Nephrogenic adenoma has no typical features, and pathologic evaluation is required for diagnosis. Although imaging features of malacoplakia are also nonspecific, characteristic Michaelis-Gutmann bodies are found at pathologic evaluation. The various types of cystitis (cystitis cystica, cystitis glandularis, and eosinophilic cystitis) require pathologic diagnosis. Bladder infection with tuberculosis and schistosomiasis produces nonspecific bladder wall thickening and ulceration in the acute phase and should be suspected in patients who are immunocompromised or from countries where these infections are common. The diagnosis of chemotherapy cystitis and radiation cystitis should be clinically evident, but imaging may be used to determine severity and to assess complications. Extrinsic inflammatory diseases such as Crohn disease and diverticulitis may be associated with fistulas to the bladder and focal bladder wall abnormality. The extravesical findings allow the diagnosis to be made easily. Finally, extrinsic masses arising from the prostate or distal ureter may cause filling defects, which can be confused with intrinsic bladder masses.

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.

Hematospermia: imaging findings

Hematospermia is an anxiety provoking but otherwise generally benign and self-limited condition that is infrequently associated with significant underlying pathology, and is most often considered to be idiopathic in nature. Management with routine clinical evaluation, watchful waiting, and reassurance generally suffice without further diagnostic workup or treatment. Noninvasive imaging may play an important role in the diagnostic workup of men with hematospermia, particularly in those who are >40 years old, have other associated symptoms or signs of disease, or have persistence of hematospermia. Many entities may be encountered in association with hematospermia at imaging, and specific therapeutic interventions may be used if certain treatable underlying pathologies are coincidentally detected. In this comprehensive review, we discuss the potential etiologies, diagnostic workup, imaging techniques, relevant male pelvic anatomy, imaging appearance of specific associated pathologies, and treatment for hematospermia.

Value of routine renal and abdominal ultrasonography in patients undergoing prostatectomy

OBJECTIVE

To evaluate the frequency of urological and non-urological abnormalities detected on routine renal and abdominal ultrasonography in patients undergoing surgery for benign prostatic hyperplasia (BPH) and to see if they affected the intended decision for prostate surgery.

METHODS

Medical records of 250 patients who underwent open or endoscopic surgery for BPH at Nishtar Hospital, Multan, Pakistan between May 2003 and December 2004 were studied. All patients had abdominal ultrasonography performed during routine preoperative workup. The frequency of urological and non-urological conditions detected on ultrasonography was calculated and the effect of these conditions on the intended decision for prostate surgery was observed.

RESULTS

In 102 patients (40.8%) urological and in 8 patients (3.2%) non-urological abnormalities were detected by ultrasonography. Urological conditions detected included uni/bilateral hydronephrosis (34 pts), vesical stones (34 pts), renal cysts (15 pts), renal stones (6 pts), small shrunken kidneys (2 pts), renal tumour (1 pt) and bladder carcinoma (1 pt). Non-urological conditions included gall stones (4 pts), liver abscess (2 pts), hydatid cyst (1 pt) and liver carcinoma (1 pt).

CONCLUSION

The study shows that a sizeable number of patients (44%) had urological and non-urological conditions detected by renal and abdominal ultrasonography. Most patients had benign conditions but three of these patients had potentially life threatening conditions (renal, bladder and hepatic carcinoma) detected by sonography that were unrelated to the prostate. However, in only one patient (0.4%) with bladder carcinoma, surgery for prostate was postponed and bladder tumour was dealt with prior to transurethral resection of prostate (TURP). Various conditions detected by ultrasonography would have been missed if it had not been performed. As ultrasonography is a non-invasive, cost-effective and quite a safe imaging technique, in author's opinion abdominal and renal tract evaluation by ultrasonography should be routinely performed in patients undergoing surgery for BPH.

Biexponential characterization of prostate tissue water diffusion decay curves over an extended b-factor range

Detailed measurements of water diffusion within the prostate over an extended b-factor range were performed to assess whether the standard assumption of monoexponential signal decay is appropriate in this organ. From nine men undergoing prostate MR staging examinations at 1.5 T, a single 10-mm-thick axial slice was scanned with a line scan diffusion imaging sequence in which 14 equally spaced b factors from 5 to 3,500 s/mm(2) were sampled along three orthogonal diffusion sensitization directions in 6 min. Due to the combination of long scan time and limited volume coverage associated with the multi-b-factor, multidirectional sampling, the slice was chosen online from the available T2-weighted axial images with the specific goal of enabling the sampling of presumed noncancerous regions of interest (ROIs) within the central gland (CG) and peripheral zone (PZ). Histology from prescan biopsy (n=9) and postsurgical resection (n=4) was subsequently employed to help confirm that the ROIs sampled were noncancerous. The CG ROIs were characterized from the T2-weighted images as primarily mixtures of glandular and stromal benign prostatic hyperplasia, which is prevalent in this population. The water signal decays with b factor from all ROIs were clearly non-monoexponential and better served with bi- vs. monoexponential fits, as tested using chi(2)-based F test analyses. Fits to biexponential decay functions yielded intersubject fast diffusion component fractions in the order of 0.73+/-0.08 for both CG and PZ ROIs, fast diffusion coefficients of 2.68+/-0.39 and 2.52+/-0.38 microm(2)/ms and slow diffusion coefficients of 0.44+/-0.16 and 0.23+/-0.16 um(2)/ms for CG and PZ ROIs, respectively. The difference between the slow diffusion coefficients within CG and PZ was statistically significant as assessed with a Mann-Whitney nonparametric test (P<.05). We conclude that a monoexponential model for water diffusion decay in prostate tissue is inadequate when a large range of b factors is sampled and that biexponential analyses are better suited for characterizing prostate diffusion decay curves.

Magnetic resonance-guided prostate interventions

We review our experience using an open 0.5-T magnetic resonance (MR) interventional unit to guide procedures in the prostate. This system allows access to the patient and real-time MR imaging simultaneously and has made it possible to perform prostate biopsy and brachytherapy under MR guidance. We review MR imaging of the prostate and its use in targeted therapy, and describe our use of image processing methods such as image registration to further facilitate precise targeting. We describe current developments with a robot assist system being developed to aid radioactive seed placement.

Assessing prostate volume by magnetic resonance imaging: a comparison of different measurement approaches for organ volume analysis

OBJECTIVES

We sought to evaluate the capabilities of different magnetic resonance imaging (MRI)-based methodologies for measuring prostate volume.

MATERIALS AND METHODS

Twenty-four male beagles with benign prostatic hyperplasia were enrolled in a drug trial and imaged at 5 time points. A total of 120 prostate volumes were determined by MRI-based semiautomated segmentation. For planimetric assessment, 8 diameter locations were determined in the axial and coronal plane of the MRI slice with maximum extension of the prostate. Thirteen calculation models based on these diameters were determined by comparison to the reference volume and evaluated during treatment.

RESULTS

The segmented MRI prostate volume significantly correlated with post necropsy volume. The best diameter-based model also worked very well for monitoring prostate volume of dogs under treatment.

CONCLUSIONS

MRI-based segmentation is highly accurate in assessing prostate volume. Diameter-based measurements are closely correlated to the segmented prostate volume and are feasible to monitor therapy.

Prevalence of lower urinary tract symptoms in men aged 45-79 years: a population-based study of 40 000 Swedish men

OBJECTIVE

To estimate the age-specific prevalence and severity of lower urinary tract symptoms (LUTS) among Swedish men, the intercorrelations between different symptoms, and to assess quality of life and health-seeking behaviour among men with LUTS.

SUBJECTS AND METHODS

In 1997, an International Prostate Symptom Score (IPSS) questionnaire, together with other questions about lifestyle, was mailed to all men aged 45-79 years living in two counties in Sweden; the analyses included 39 928 men.

RESULTS

Overall, 18.5% and 4.8% of the men were moderately and severely symptomatic; the prevalence of at least one symptom was 83%. LUTS were strongly age-dependent, with 1.8% of severe symptoms among men aged 45-49 years and increasing to 9.7% among those 75-79 years old. Frequent urination was the most common symptom among men aged < 70 years and nocturia among those aged >70 years. Symptoms like hesitancy, poor flow and intermittency were highly correlated with each other (Spearman coefficients 0.56-0.60). There was a high correlation between the IPSS and a poor score for quality of life resulting from the bothersomeness of LUTS (r = 0.70). Among symptomatic subjects, 36% reported a poor quality of life (fairly bad, very bad or terrible). Only 29% of symptomatic subjects (IPSS >7) reported that they had been diagnosed previously for their urinary problems, and only 11% received medication for that.

CONCLUSION

Although the prevalence of LUTS in Sweden is high, the percentage of men whose quality of life is substantially affected is much lower.

A case-based evaluation of SRD5A1, SRD5A2, AR, and ADRA1A as candidate genes for severity of BPH

In men with a clinical diagnosis of benign prostatic hyperplasia (BPH), polytomous logistic regression analysis was conducted to evaluate associations between two silent polymorphisms in SRD5A1 (codon positions 30 and 116), two polymorphisms in SRD5A2 (Val89Leu substitution and C to T transition in intron 1), a trinucleotide (CAG)n repeat in androgen receptor (AR), and an Arg492Cys substitution in ADRA1A and clinical parameters that characterize severity of BPH. Candidate gene selection was based on two mechanistic pathways targeted by pharmacotherapy for BPH: (1) androgen metabolic loci contributing to prostate growth (static obstruction); and (2) factors affecting smooth muscle tone (dynamic obstruction). Polymorphisms in SRD5A2 were not associated with severity of BPH; however, SRD5A1 polymorphisms were associated with severity of BPH. The process(es) in which these silent single-nucleotide polymorphisms (SNPs) influence BPH phenotypes is unknown and additional studies will be needed to assess whether these SNPs have direct functional consequences. The characterization of additional molecular factors that contribute to static and dynamic obstruction may help predict response to pharmacotherapy and serve to identify novel drug targets for the clinical management of BPH.

Endorectal diffusion-weighted imaging in prostate cancer to differentiate malignant and benign peripheral zone tissue

PURPOSE

To determine if the apparent diffusion coefficient (ADC) can discriminate benign from malignant peripheral zone (PZ) tissue in patients with biopsy-proven prostate cancer that have undergone endorectal diffusion-weighted imaging (DWI) of the prostate.

MATERIALS AND METHODS

Ten patients with prostate cancer underwent endorectal magnetic resonance imaging (MRI) in addition to DWI. A two-dimensional grid was placed over the axial images, and each voxel was graded by a 4-point rating scale to discriminate nonmalignant from malignant PZ tissue based on MR images alone. ADC was then determined for each voxel and plotted for nonmalignant and malignant voxels for the entire patient set. Second, with the radiologist aware of biopsy locations, any previously assigned voxel grade that was inconsistent with biopsy data was regrouped and ADCs were replotted.

RESULTS

For the entire patient set, without and with knowledge of the biopsy data, the mean ADCs for nonmalignant and malignant tissue were 1.61 +/- 0.27 and 1.34 +/- 0.38 x 10(-3) mm2/second (P = 0.002) and 1.61 +/- 0.26 and 1.27 +/- 0.37 x 10(-3) mm2/second (P = 0.0005), respectively.

CONCLUSION

DWI of the prostate is possible with an endorectal coil. The mean ADC for malignant PZ tissue is less than nonmalignant tissue, although there is overlap in individual values.