Deep Learning Prostate MRI Segmentation Accuracy and Robustness: A Systematic Review.

Purpose To investigate the accuracy and robustness of prostate segmentation using deep learning across various training data sizes, MRI vendors, prostate zones, and testing methods relative to fellowship-trained diagnostic radiologists. Materials and Methods In this systematic review, Embase, PubMed, Scopus, and Web of Science databases were queried for English-language articles using keywords and related terms for prostate MRI segmentation and deep learning algorithms dated to July 31, 2022. A total of 691 articles from the search query were collected and subsequently filtered to 48 on the basis of predefined inclusion and exclusion criteria. Multiple characteristics were extracted from selected studies, such as deep learning algorithm performance, MRI vendor, and training dataset features. The primary outcome was comparison of mean Dice similarity coefficient (DSC) for prostate segmentation for deep learning algorithms versus diagnostic radiologists. Results Forty-eight studies were included. Most published deep learning algorithms for whole prostate gland segmentation (39 of 42 [93%]) had a DSC at or above expert level (DSC ≥ 0.86). The mean DSC was 0.79 ± 0.06 (SD) for peripheral zone, 0.87 ± 0.05 for transition zone, and 0.90 ± 0.04 for whole prostate gland segmentation. For selected studies that used one major MRI vendor, the mean DSCs of each were as follows: General Electric (three of 48 studies), 0.92 ± 0.03; Philips (four of 48 studies), 0.92 ± 0.02; and Siemens (six of 48 studies), 0.91 ± 0.03. Conclusion Deep learning algorithms for prostate MRI segmentation demonstrated accuracy similar to that of expert radiologists despite varying parameters; therefore, future research should shift toward evaluating segmentation robustness and patient outcomes across diverse clinical settings. Keywords: MRI, Genital/Reproductive, Prostate Segmentation, Deep Learning Systematic review registration link: osf.io/nxaev © RSNA, 2024.

FEATURES OF PRENATAL MORPHOGENESIS AND PECULARITIES OF THE UTRICULUS PROSTATICUS FETAL ANATOMY.

OBJECTIVE: Aim: To determine the peculiarities of the structural organization of the utriculus prostaticus (UP) in pre-fetuses and fetuses. PATIENTS AND METHODS: Materials and methods: The study of macroscopic features and microscopic peculiarities of the prostate gland and the prostatic part of the urethra was carried out on 46 sections of human pre-fetuses and fetuses aged from 9 weeks to birth (31,0-375,0 mm PCL). The work uses the method of microscopic study of serial histological and topographic-anatomical specimens of the prostate gland, as well as the method of the thin preparation of the prostate part of the urethra in fetuses of different ages and morphometry. RESULTS: Results: In 58,0-66,0 mm PCL fetuses the paramesonephric ducts are reduced, except of their connected caudal part, which is a morphological substrate for the development of the UP. At 72,0-79,0 mm PCL fetuses, cavity is replaced by cellular mass. At the 85,0-120,0 mm PCL fetuses, the UP connects with the lumen of the urethra. The cavity of the UP intensivelly proliferates with cells. In fetuses of 125,0-135,0 mm PCL is presente dense arrangement of glandular elements, which are surrounded by fibrous-muscular membrane. In fetuses of 150,0-160,0 mm PCL, in the caudal direction, the cavity of the UP gradually narrows, it forms invaginations, especially in the middle and lower parts, or is divided into separate, interconnected chambers. In fetuses of 170,0-185,0 mm PCL, UP has elongated-oval or rounded-oval shape. In the caudal direction, the UP is directed ventral to the colliculus seminalis and is located slightly anterior and superior to the ejaculatory ducts. In 8-month-old fetuses, the lumen of the UP is lined with a pseudostratified cubical epithelium, outside of which there is a tunica muscularis. Ejaculatory ducts lined with a two-layer cuboidal epithelium are placed on both sides of the UP. A 270,0 mm PCL fetus has no UP at the apex of the colliculus seminalis. In fetuses 315,0-335,0 mm PCL, the process of cavity formation spreads to new areas of glandular formations of the prostate gland and their final branches. Most of the glandular formations open into the prostatic part of the urethra directly below the UP and the distal parts of the ejaculatory ducts. Microscopic examination of frontal sections of the prostate gland of a fetus with a 360,0 mm PCL revealed a septum in the UP which divides the cavity of the UP into the right and left halves of a round-oval shape. CONCLUSION: Conclusions: The formation of utriculus prostaticus occurs from the paramesonephric ducts in the 11th week of fetal development. At the beginning of the 4th month of intrauterine development, it gradually decreases in size. From the middle of the 5th month of prenatal development, the utriculus prostaticus lengthens, and starting from the fetus of 7 months, both its length and width increase. At the end of the fetal period, the utriculus prostaticus acquires a round-oval shape, its length increases from 0,5 to 4,3 mm during prenatal ontogeny.

A pair of deep learning auto-contouring models for prostate cancer patients injected with a radio-transparent versus radiopaque hydrogel spacer.

BACKGROUND: Absorbable hydrogel spacer injected between prostate and rectum is gaining popularity for rectal sparing. The spacer alters patient anatomy and thus requires new auto-contouring models. PURPOSE: To report the development and comprehensive evaluation of two deep-learning models for patients injected with a radio-transparent (model I) versus radiopaque (model II) spacer. METHODS AND MATERIALS: Model I was trained and cross-validated by 135 cases with transparent spacer and tested on 24 cases. Using refined training methods, model II was trained and cross-validated by the same dataset, but with the Hounsfield Unit distribution in the spacer overridden by that obtained from ten cases with opaque spacer. Model II was tested on 64 cases. The models auto-contour eight regions of interest (ROIs): spacer, prostate, proximal seminal vesicles (SVs), left and right femurs, bladder, rectum, and penile bulb. Qualitatively, each auto contour (AC), as well as the composite set, was assessed against manual contour (MC), by a radiation oncologist using a 1 (accepted directly or after minor editing), 2 (accepted after moderate editing), 3 (accepted after major editing), and 4 (rejected) scoring scale. The efficiency gain was characterized by the mean score as nearly complete [1-1.75], substantial (1.75-2.5], meaningful (2.5-3.25], and no (3.25-4.00]. Quantitatively, the geometric similarity between AC and MC was evaluated by dice similarity coefficient (DSC) and mean distance to agreement (MDA), using tolerance recommended by AAPM TG-132 Report. The results by the two models were compared to examine the outcome of the refined training methods. The large number of testing cases for model II allowed further investigation of inter-observer variability in clinical dataset. The correlation between score and DSC/MDA was studied on the ROIs with 10 or more counts of each acceptable score (1, 2, 3). RESULTS: For model I/model II: the mean score was 3.63/1.30 for transparent/opaque spacer, 2.71/2.16 for prostate, 3.25/2.44 for proximal SVs, 1.13/1.02 for both femurs, 2.25/1.25 for bladder, 3.00/2.06 for rectum, 3.38/2.42 for penile bulb, and 2.79/2.20 for the composite set; the mean DSC was 0.52/0.84 for spacer, 0.84/0.85 for prostate, 0.60/0.62 for proximal SVs, 0.94/0.96 for left femur, 0.95/0.96 for right femur, 0.91/0.95 for bladder, 0.81/0.84 for rectum, and 0.65/0.65 for penile bulb; and the mean MDA was 2.9/0.9 mm for spacer, 1.9/1.7 mm for prostate, 2.4/2.3 mm for proximal SVs, 0.8/0.5 mm for left femur, 0.7/0.5 mm for right femur, 1.5/0.9 mm for bladder, 2.3/1.9 mm for rectum, and 2.2/2.2 mm for penile bulb. Model II showed significantly improved scores for all ROIs, and metrics for spacer, femurs, bladder, and rectum. Significant inter-observer variability was only found for prostate. Highly linear correlation between the score and DSC was found for the two qualified ROIs (prostate and rectum). CONCLUSIONS: The overall efficiency gain was meaningful for model I and substantial for model II. The ROIs meeting the clinical deployment criteria (mean score below 3.25, DSC above 0.8, and MDA below 2.5 mm) included prostate, both femurs, bladder and rectum for both models, and spacer for model II.

Comparative analysis of male reproductive accessory glands in bats Histiotus velatus (Vespertilionidae), Molossus rufus (Molossidae), and Peropteryx leucoptera (Emballonuridae).

Despite the high number of species and wide geographic dispersion, reproductive accessory glands (RAGs) of bats have traditionally received little attention in the literature, with some species not even having a basic description of their composition and structure. Thus, this study aimed to analyze and compare the composition, anatomy, and histology of male RAGs of bat species belonging to three of the largest (cosmopolitan) bat families: Vespertilionidae (Histiotus velatus), Molossidae (Molossus rufus), and Emballonuridae (Peropteryx leucoptera), in order to understand the variations in the bat RAGs. The results showed that the RAGs of H. velatus, M. rufus, and P. leucoptera are composed of an intra-abdominal prostatic complex, associated with the urethra, urethral glands, and a pair of inguinal bulbourethral glands; without ampullary glands or seminal vesicles. The prostatic complex can be composed of two (M. rufus and P. leucoptera) or three (H. velatus) prostatic regions, and can be compact (P. leucoptera), semi-lobed (M. rufus), or multilobed (H. velatus). Each prostatic region has unique and distinct characteristics, with the ventral region presenting a holocrine nature, exclusive to bats; while the dorsal and/or dorsolateral regions have similar characteristics to the ventral prostate of rats and to the human peripheral zone.

Deep learning algorithm performs similarly to radiologists in the assessment of prostate volume on MRI.

OBJECTIVES: Prostate volume (PV) in combination with prostate specific antigen (PSA) yields PSA density which is an increasingly important biomarker. Calculating PV from MRI is a time-consuming, radiologist-dependent task. The aim of this study was to assess whether a deep learning algorithm can replace PI-RADS 2.1 based ellipsoid formula (EF) for calculating PV. METHODS: Eight different measures of PV were retrospectively collected for each of 124 patients who underwent radical prostatectomy and preoperative MRI of the prostate (multicenter and multi-scanner MRI's 1.5 and 3 T). Agreement between volumes obtained from the deep learning algorithm (PVDL) and ellipsoid formula by two radiologists (PVEF1 and PVEF2) was evaluated against the reference standard PV obtained by manual planimetry by an expert radiologist (PVMPE). A sensitivity analysis was performed using a prostatectomy specimen as the reference standard. Inter-reader agreement was evaluated between the radiologists using the ellipsoid formula and between the expert and inexperienced radiologists performing manual planimetry. RESULTS: PVDL showed better agreement and precision than PVEF1 and PVEF2 using the reference standard PVMPE (mean difference [95% limits of agreement] PVDL: -0.33 [-10.80; 10.14], PVEF1: -3.83 [-19.55; 11.89], PVEF2: -3.05 [-18.55; 12.45]) or the PV determined based on specimen weight (PVDL: -4.22 [-22.52; 14.07], PVEF1: -7.89 [-30.50; 14.73], PVEF2: -6.97 [-30.13; 16.18]). Inter-reader agreement was excellent between the two experienced radiologists using the ellipsoid formula and was good between expert and inexperienced radiologists performing manual planimetry. CONCLUSION: Deep learning algorithm performs similarly to radiologists in the assessment of prostate volume on MRI. KEY POINTS: • A commercially available deep learning algorithm performs similarly to radiologists in the assessment of prostate volume on MRI. • The deep-learning algorithm was previously untrained on this heterogenous multicenter day-to-day practice MRI data set.

Dosimetric verification of IMRT and 3D conformal treatment delivery using EPID.

PURPOSE: Electronic portal imaging devices (EPIDs) could potentially be useful for either in-vivo or pre-treatment dosimetric verification of external beam radiation therapy. The accuracy of EPID for dosimetric purposes is highly dependent on the specific method used for the determination of dose-response characteristics. The aim of this study was to develop a simple and time-saving EPID back-projection dosimetry algorithm for 2D dose verification in 3D conformal and intensity-modulated beams. METHODS: The procedure of dose reconstruction includes a first calibration step using ionization chamber measurements to convert the Electronic Portal Image (EPI) pixel values into an absorbed dose in water. Subsequently, several corrections were applied to the Portal Dose Images (PDIs) for the effect of field size, attenuator thickness, scattering radiation, beam hardening and EPID off-axis response. Furthermore, to consider tissue inhomogeneity for accurate dose reconstruction, the patient's water equivalent path length (WEPL) was calculated using a range of digitally reconstructed radiographs (DRRs) obtained at various thicknesses by Plastimatch software. The EPID-derived dose maps accuracy was assessed by comparing with the treatment planning system (TPS) calculated dose in the prostate region of Alderson phantom irradiated with 3D conformal and intensity-modulated beams. RESULTS: The gamma analysis for the dose plane showed agreements of 96.95% and 93.5% for 3D conformal and IMRT fields, respectively, with 3%/3 mm acceptance criteria. CONCLUSION: The presented algorithm can provide accurate absolute 2D dose maps for clinical use in the context of 3DCRT or IMRT Quality Assurance (QA) programs.

Zonal anatomy of the prostate using magnetic resonance imaging, morphometrics, and radiomic features: impact of age-related changes.

OBJECTIVE: To evaluate the impact of age on the zonal anatomy of the prostate by MRI using morphometric and textural analysis. METHODS: A total of 154 men (mean age: 63 years) who underwent MRI due to a high prostate-specific antigen (PSA) level were included retrospectively. At each MRI examination the following variables were measured: overall dimensions of the prostate (whole gland (WG), transitional zone (TZ), and peripheral zone (PZ)), and thickness of the anterior fibromuscular stroma (AFMS) and the periprostatic venous plexus (PPVP) on T2 weighted images. Identical regions of interest (ROIs) were delineated on the apparent diffusion coefficient (ADC) map on the anterior (horn) and posterior part of the PZ. Textural (TexRAD®) parameter differences between TZ and PZ ROIs on T2 weighted images were analyzed by linear regression. Results were correlated with age (distributed into five decades from 22 to 89 years). RESULTS: Age was positively correlated with PSA level and glandular volumes (WG, TZ, and TZ/WG ratio; p < 0.0001) and was negatively correlated with AFSM and PPVP thickness (p < 0.0001). There was a positive correlation between ADC values of the PZ and age (p = 0.003) and between entropy of the TZ and PZ and age (p < 0.001). CONCLUSION: Gradual variations in morphologic and textural features of the prostate were observed with age, mainly due to the increase in TZ volume while PZ volume tended to decrease. These modifications resulted in textural changes mainly at the expense of entropy. ADVANCES IN KNOWLEDGE: Entropy could be relevant for studying the process of aging of the prostate.

Relationship between serum total testosterone and prostate volume in aging men.

Total testosterone levels decline with age, while prostate volume and the prevalence of benign prostatic hyperplasia increase with age. We sought to investigate the correlation of serum testosterone levels with prostate volume in aging men. We analyzed clinical data obtained from 416 ostensibly healthy men who underwent routine health check-ups and recruited and collected data from these subjects 4 years later. We analyzed the correlation between prostate volume and relevant factors, as well as the correlation between changes in prostate volume and low testosterone over a 4-year period. Men with low testosterone had significantly larger prostate volume than those in the normal testosterone group (26.86 ± 8.75 vs. 24.06 ± 6.77 P = 0.02), and subjects with low testosterone had significantly higher levels of obesity-related factors, including waist circumference, body mass index, and insulin (all P < 0.001). After adjustment for age, testosterone level was negatively correlated with prostate volume (P = 0.004), and prostate volume and 4-year changes in prostate volume were associated with low testosterone. With increased testosterone level, prostate volume showed a significant linear decreasing trend. These findings provide evidence of the relationship between testosterone and prostate volume. Additional large studies are needed to confirm these preliminary results.

Prenatal and pubertal exposure to 17α-ethinylestradiol cause morphological changes in the prostate of old gerbils.

This study evaluated such as exposure to ethinylestradiol during the prenatal (18th-22nd day) and pubertal (42nd-49th day) periods acts on the male ventral prostate and female prostate of 12-month old gerbils. We performed the analysis to serum hormone levels for estradiol and testosterone. The prostates were submitted to morphometric and immunohistochemical analyses. Exposure to ethinylestradiol during these developmental periods decreased the testosterone serum levels in males and increased the estradiol serum levels in females. Morphologically, prostate intraepithelial neoplasia and disorders in the arrangement of the fibrous components were observed in the prostate glands of both sexes of gerbil exposed to ethinylestradiol during development periods. In the male prostate, the ethinylestradiol promoted decreased in the frequency of positive epithelial cell for androgen receptor (AR) and increased the frequency of positive stromal cell for estrogen receptor α. However, in the female prostate, this synthetic estrogen caused AR upregulation and increased cell proliferation. This study shows that the exposure to ethinylestradiol during development phases alters the morphology and the hormonal signaling in the male and female prostates of old gerbils, confirming the action of ethinylestradiol as endocrine disruptor.

Novel anatomical apical dissection utilizing puboprostatic "open-collar" technique: Impact on apical surgical margin and early continence recovery.

PURPOSE: To evaluate the impact of modifications to anatomical apical dissection including a puboprostatic open-collar technique, which visualizes the lateral aspect of the apex and dorsal vein complex (DVC) covering the rhabdosphincter while preserving the puboprostatic collar, on positive surgical margin (PSM) and continence recovery. METHODS: One-hundred-and-sixty-seven patients underwent gasless single-port retroperitoneoscopic radical prostatectomy using a three-dimensional head-mounted display system. Sequentially modified surgical techniques comprised puboprostatic open-collar technique, sutureless transection of the DVC, retrograde urethral dissection, and anterior reconstruction. The associations of these modifications with PSM and continence recovery were assessed. RESULTS: The puboprostatic open-collar technique, sutureless DVC transection, and retrograde urethral dissection were significantly associated with lower apical PSM (P = 0.003, 0.003, and 0.010, respectively). The former two also showed similar associations in 84 patients with anterior apical tumor (P = 0.021 and 0.030, respectively). Among 92 patients undergoing all of these three procedures, overall and apical PSM rates were 13.0% and 3.3%, respectively. Retrograde urethral dissection (odds ratio [OR] 2.73, P = 0.004) together with nerve sparing (OR 2.77, P = 0.003) and anterior apical tumor (OR 0.45, P = 0.017) were independently associated with immediate continence recovery. A multivariable model for 3-month continence recovery included anterior apical tumor (OR 0.28, P = 0.003) and puboprostatic open-collar technique (OR 3.42, P = 0.062). Immediate and 3-month continence recovery rates were 56.3% and 85.4%, respectively, in 103 patients undergoing both the puboprostatic open-collar technique and retrograde urethral dissection. CONCLUSION: Novel anatomical apical dissection utilizing a puboprostatic open-collar technique may favorably impact on both apical surgical margin and continence recovery.

Effect of prostatic apex shape (Lee types) and urethral sphincter length in preoperative MRI on very early continence rates after radical prostatectomy.

PURPOSE: To test the effect of anatomic variants of the prostatic apex overlapping the membranous urethra (Lee type classification), as well as median urethral sphincter length (USL) in preoperative multiparametric magnetic resonance imaging (mpMRI) on the very early continence in open (ORP) and robotic-assisted radical prostatectomy (RARP) patients. METHODS: In 128 consecutive patients (01/2018-12/2019), USL and the prostatic apex classified according to Lee types A-D in mpMRI prior to ORP or RARP were retrospectively analyzed. Uni- and multivariable logistic regression models were used to identify anatomic characteristics for very early continence rates, defined as urine loss of ≤ 1 g in the PAD-test. RESULTS: Of 128 patients with mpMRI prior to surgery, 76 (59.4%) underwent RARP vs. 52 (40.6%) ORP. In total, median USL was 15, 15 and 10 mm in the sagittal, coronal and axial dimensions. After stratification according to very early continence in the PAD-test (≤ 1 g vs. > 1 g), continent patients had significantly more frequently Lee type D (71.4 vs. 54.4%) and C (14.3 vs. 7.6%, p = 0.03). In multivariable logistic regression models, the sagittal median USL (odds ratio [OR] 1.03) and Lee type C (OR: 7.0) and D (OR: 4.9) were independent predictors for achieving very early continence in the PAD-test. CONCLUSION: Patients' individual anatomical characteristics in mpMRI prior to radical prostatectomy can be used to predict very early continence. Lee type C and D suggest being the most favorable anatomical characteristics. Moreover, longer sagittal median USL in mpMRI seems to improve very early continence rates.

The distribution pattern of periprostatic neurovascular bundles examined with successive celloidin slices.

BACKGROUND: Although several distribution patterns of periprostatic neurovascular bundles have been proposed, variant dissection technique based on these patterns still confused surgeons. The aim of this study was to describe the periprostatic neurovascular bundles and their relationship with the fascicles around prostate and provide the accurate morphologic knowledge of periprostatic tissue for prostate operation. METHODS: The pelvic viscera were obtained from 26 adult male cadavers. They were embedded in celloidin and cut into successive slices. The slices were explored with anatomic microscopy. 3-Dimensional reconstruction was achieved with celloidin sections and series software. RESULTS: The prostatic capsule which surrounded the dorsal, bilateral aspect of the prostate was attached ventrally to anterior fibrous muscular stroma (AFMS). The lower part of the striated sphincter completely embraced the urethral; the upper part of this muscle covered the lower ventral surface of prostate. The upper ventral surface of prostate is covered by the circular muscle of detrusor. The levator fascia and the capsule adhered on the most convex region of the lateral prostate, but separated on the other region. The pelvic neurovascular bundles (PNVB) divided into the anterior and posterior divisions. The anterior division continued as dorsal vascular complex (DVC). The distal part of DVC entered into penile hilum. The posterior division continued as neurovascular bundles, and then as the cavernous supply (CS). The distal part of CS joined into pudendal neurovascular bundles. CONCLUSIONS: The capsule and AFMS formed a pocket like complex. There were anterior and posterior neurovascular approaches from PNVB to penile hilum.

Evaluation of margins in pelvic lymph nodes and prostate radiotherapy and the impact of bladder and rectum on prostate position.

PURPOSE: The aims of this study were: determination of the CTV to PTV margins for prostate and pelvic lymph nodes. Investigation of the impact of registration modality (pelvic bones or prostate) on the CTV to PTV margins of pelvic lymph nodes. Investigation of the variations of bladder and rectum over the treatment course. Investigation of the impact of bladder and rectum variations on prostate position. PATIENTS AND METHODS: This study included 15 patients treated for prostate adenocarcinoma. Daily kilo voltage images and weekly CBCT scans were performed to assess prostate displacements and common and external iliac vessels motion. These data was used to calculate the CTV to PTV margins using Van Herk equation in the setting of a daily bone registration. We also compared the CTV to PTV margins of pelvic lymph nodes according to registration method; based on pelvic bone or prostate. We delineated bladder and rectum on all CBCT scans to assess their variations over treatment course at 4 anatomic levels [1.5cm above pubic bone (PB), superior edge, mid- and inferior edge of PB]. RESULTS: Using Van Herk equation, the prostate CTV to PTV margins (bone registration) were 8.03mm, 5.42mm and 8.73mm in AP, ML and SI direction with more than 97% of prostate displacements were less than 5mm. The CTV to PTV margins ranged from 3.12mm to 3.25mm for external iliac vessels and from 3.12mm to 4.18mm for common iliac vessels. Compared to registration based on prostate alignment, bone registration resulted in an important reduction of the CTV to PTV margins up to 54.3% for external iliac vessels and up to 39.6% for common iliac vessels. There was no significant variation of the mean bladder volume over the treatment course. There was a significant variation of the mean rectal volume before and after the third week of treatment. After the third week, the mean rectal volume seemed to be stable. The uni- and multivariate analysis identified the anterior wall of rectum as independent factor acting on prostate motion in AP direction at 2 levels (superior edge of, mid PB). The right rectal wall influenced the prostate motion in ML direction at inferior edge of PB. The bladder volume tends toward significance as factor acting on prostate motion in AP direction. CONCLUSIONS: We recommend CTV to PTV margins of 8mm, 6mm and 9mm in AP, ML and SI directions for prostate. And, we suggest 4mm and 5mm for external and common iliac vessels respectively. We also prefer registration based on bony landmarks to minimize bowel irradiation. More CBCT scans should be performed during the first 3weeks and especially the first week to check rectum volume.

Prostatic anatomical parameters correlate with clinical characteristics suggestive of benign prostatic hyperplasia.

We conducted the present study to assess the correlation of the prostatic anatomical parameters, especially the ratio of peripheral zone thickness and transitional zone thickness, with clinical and uroflowmetry characteristics suggestive of benign prostate hyperplasia (BPH). A total of 468 consecutive patients with a detailed medical history were identified. All patients were evaluated by scoring subjective symptoms with the International Prostate Symptom Score (IPSS) and quality of life (QoL). The prostatic anatomical parameters were measured using transrectal ultrasonography, and postvoid residual urine and maximum flow rate (Qmax) values were also determined. Pearson's correlation analysis revealed that both total prostate volume (TPV; r = 0.160, P < 0.001) and transitional zone volume (TZV; r = 0.104, P = 0.016) increased with patients' age; however, no correlations were observed of TPV, TZV, transitional zone index (TZI), and transitional zone thickness (TZT) with IPSS or QoL (all P >0.05). Peripheral to transitional zone index (PTI) was found negatively correlated with total IPSS (r = -0.113, P = 0.024), storage IPSS (r = -0.103, P = 0.041), and voiding IPSS (r = -0.123, P = 0.014). As regards the uroflowmetry characteristics, PTI (r = 0.157, P = 0.007) was indicated to be positively correlated with Qmaxand negatively correlated with TZI (r = -0.119, P = 0.042) and TZT (r = -0.118, P = 0.045), but not correlated with TPV, TZV, or peripheral zone thickness (PZT) (all P > 0.05). Postvoid residual urine (PVR) had not correlated with all the prostatic anatomical variables (all P > 0.05). This is the first study that formally proposed the concept of PTI, which is an easy-to-measure prostate anatomical parameter which significantly correlates with total IPSS, storage IPSS, voiding IPSS, and Qmax, suggesting that PTI would be useful in evaluating and managing men with lower urinary tract symptoms (LUTS)/BPH. However, well-designed studies are mandatory to verify the clinical utility of PTI.

Role of sparing of puboprostatic ligaments on continence recovery after radical prostatectomy: a randomized controlled trial.

OBJECTIVE: Sparing of puboprostatic ligaments (PPLs) during radical prostatectomy was introduced as a technique to improve urinary continence. This study aims to study the effect of sparing of PPLs during laparoscopic radical prostatectomy in terms of continence during the first 3 months. METHODS: A total of 74 patients, diagnosed with clinically localized prostate cancer, were randomly assigned to two equal groups; PPLs division and sparing during LRP. Based on the number of daily used pads, both groups completed 3 months follow-up to assess continence recovery. The effects of age, preoperative total prostate-specific antigen (PSA) and clinical tumor stage on continence recovery were also studied. The study was registered and approved by the Ethics Committee of Alexandria University-Faculty of Medicine (Protocol No. 0201074). RESULTS: Seventy-four patients were enrolled, with a mean age of 63.8 years. Baseline characteristics were comparable, except significantly higher mean PSA in the division group. Sixty patients were continent (0-1 pad/day) at 3 months follow-up. Continence was significantly better in the sparing than division group at 1 week after catheter removal (67.6% vs 40.5%, p = 0.01), at 1 month (73% vs 45.9%, p = 0.009) and 2 months (89.2% vs 51.4%, p = 0.0001). At 3 months follow-up, there was no significant difference between both groups (83.3% vs 78.4% for sparing and division groups, respectively; p = 0.28). Moreover, continence was significantly improved at 3 months compared to 1 week in both groups. CONCLUSION: Sparing of puboprostatic ligaments during radical prostatectomy significantly improves postoperative early recovery of urinary continence.

Prostate Bed Delineation Guidelines for Postoperative Radiation Therapy: On Behalf Of The Francophone Group of Urological Radiation Therapy.

PURPOSE: Prostate bed (PB) irradiation is considered the standard postoperative treatment after radical prostatectomy (RP) for tumors with high-risk features or persistent prostate-specific antigen, or for salvage treatment in case of biological relapse. Four consensus guidelines have been published to standardize practices and reduce the interobserver variability in PB delineation but with discordant recommendations. To improve the reproducibility in the PB delineation, the Francophone Group of Urological Radiotherapy (Groupe Francophone de Radiothérapie Urologique [GFRU]) worked to propose a new and more reproducible consensus guideline for PB clinical target volume (CTV) definition. METHODS AND MATERIALS: A 4-step procedure was used. First, a group of 10 GFRU prostate experts evaluated the 4 existing delineation guidelines for postoperative radiation therapy (European Organization for Research and Treatment of Cancer; the Faculty of Radiation Oncology Genito-Urinary Group; the Radiation Therapy Oncology Group; and the Princess Margaret Hospital) to identify divergent issues. Second, data sets of 50 magnetic resonance imaging studies (25 after RP and 25 with an intact prostate gland) were analyzed to identify the relevant anatomic boundaries of the PB. Third, a literature review of surgical, anatomic, histologic, and imaging data was performed to identify the relevant PB boundaries. Fourth, a final consensus on PB CTV definition was reached among experts. RESULTS: Definitive limits of the PB CTV delineation were defined using easily visible landmarks on computed tomography scans (CT). The purpose was to ensure a better reproducibility of PB definition for any radiation oncologist even without experience in postoperative radiation therapy. CONCLUSIONS: New recommendations for PB delineation based on simple anatomic boundaries and available as a CT image atlas are proposed by the GFRU. Improvement in uniformity in PB CTV definition and treatment homogeneity in the context of clinical trials are expected.

[Relationship of prostate volume and inflammatory cell infiltration with the positive rate of prostate biopsy].

OBJECTIVE: To investigate the factors influencing the positive rate of prostate biopsy and its relationship with the prostate volume and inflammatory cell infiltration (ICI). METHODS: We retrospectively analyzed the clinical data on 230 cases of double-plane transrectal ultrasound-guided prostate biopsy in our Department of Urology, including the patients' age, body mass index (BMI), serum total prostate-specific antigen (tPSA), PSA density (PSAD), prostate volume, and ICI in the prostate tissue. We also investigated the relationship of the above factors with the pathological results of prostate biopsy by binary logistic regression analysis. RESULTS: The positive rate of prostate biopsy was 38.7% (89/230) in the total number of cases, 28.57% (n = 56) in the 196 cases with tPSA < 100 µg/L, and 97.06% (n = 33) in the 34 cases with tPSA ≥ 100 µg/L. Binary logistic regression analysis showed that the positive rate of prostate biopsy in those with tPSA < 100 µg/L was correlated positively with age (P < 0.01, OR = 1.09), tPSA (P < 0.01, OR = 1.04) and PSAD (P < 0.01, OR = 10.04), negatively with the prostate volume (P < 0.01, OR = 0.98) and ICI (P < 0.01, OR = 0.22), but not with BMI (P > 0.05). As a predictor of positive prostate biopsy, tPSA > 10 µg/L exhibited a sensitivity of 82.14% and a specificity of 35.71%, while PSAD > 0.26 showed a sensitivity of 78.57% and a specificity of 71.43%. CONCLUSIONS: Non-specific elevation of the tPSA level induced by increased prostate volume and inflammatory cell infiltration may lead to unnecessary biopsies in some patients. As a predictor of positive prostate biopsy, PSAD > 0.26 has a higher clinical application value than tPSA > 10 µg/L.

The Influences of Metformin on Prostate in Terms of PSA Level and Prostate Volume.

PURPOSE: The effects of metformin on prostate volume and prostate-specific antigen (PSA) were investigated. MATERIALS AND METHODS: We enrolled 384 newly diagnosed diabetes mellitus (DM) patients and 152 controls all of whom were >50 years into our prospective cross-sectional observational study. The first group contained patients receiving metformin only, the second group patients were taking a mixture of medications, including metformin plus other oral anti-diabetics, and the third was the control group. Before beginning treatment, body mass indices (BMI) of all cases were obtained. Prostate volumes were evaluated using transabdominal ultrasonography at the sixth and twelfth months. Insulin, glycosylated hemoglobin (HbA1C), insulin sensitivity index (ISI), insulin-rich growth factor (IGF-1), PSA, free PSA, and total testosterone levels were measured. RESULTS: The differences in BMI between the first and third groups were statistically significant (P < 0.05). There were no statistical differences among the groups in terms of prostate volumes (P > 0.05). The differences between the groups for insulin, HbA1C, ISI, IGF-1 (somatomedin), PSA, free PSA, and total testosterone levels were not statistically significant (P > 0.05). Free PSA and total testosterone levels in groups 1 and 2 were not statistically different at the beginning of treatment and the sixth month (p >0.05), but within groups 1 and 2, only PSA levels were different at the start of the study until completion. No differences were seen in the third group. CONCLUSION: Metformin appears to cause a decrease in PSA levels. The mechanism and any effects on prostate tissue will be studied in future randomized, prospective studies.

Developmental changes induced by exogenous testosterone during early phases of prostate organogenesis.

The aim of this study was to evaluate the impact of prenatal testosterone exposure on prostate development in male and female neonatal gerbils. Pregnant females were exposed to subcutaneous injections of testosterone cypionate (500 µg/animal) at gestational days 20 and 22. Male and female pups were then euthanized at postnatal day 1. Morphological analysis showed that females were severely affected by androgen exposure. We also observed that male and female urogenital sinus (UGS) responded differentially to testosterone treatment, demonstrating heterogeneous immunostaining for the androgen receptor (AR), estrogen receptor alpha (ERα), and proliferating cell nuclear antigen (PCNA). Smooth muscle α-actin (α-SMA) analysis showed that testosterone delays the myodifferentiation, allowing buds to reach the ectopic mesenchymes of the female UGS. Our data showed that abnormal testosterone exposure disrupted prostate organogenesis, altered the expression patterns of important markers, and demonstrated that female UGS was particularly influenced by androgen exposure during a critical window in the developmental period.

Prostate volume measurement by multiparametric magnetic resonance and transrectal ultrasound: comparison with surgical specimen weight.

OBJECTIVE: To assess accuracy of multiparametric magnetic resonance of the prostate to estimate gland volume, comparing the results with transrectal ultrasound and surgical specimen. METHODS: A retrospective study of 85 patients who underwent multiparametric magnetic resonance and transrectal ultrasound (for fusion image-guided biopsy) before radical prostatectomy. Prostate measurements were obtained from magnetic resonance axial and sagittal T2-weighted images and ultrasound; the prostate volume was determined using the ellipsoid formula. The results were compared with the surgical specimen weight. Maximum interval between multiparametric magnetic resonance imaging, transrectal ultrasound, and prostatectomy was 6 months. RESULTS: The prostate volume measured by multiparametric magnetic resonance imaging was 18-157cm3 (mean of 49.9cm3) and by transrectal ultrasound, 22-165cm3 (mean of 54.9cm3); the surgical specimen weight was 20-154g (mean of 48.6g), with no statistical differences. Based on the values obtained from imaging examinations, the prostate volume obtained was very close to the real prostatic weight, and the measures by multiparametric magnetic resonance were slightly more precise. CONCLUSION: Prostate volume measured by multiparametric magnetic resonance imaging and transrectal ultrasound showed similar values, and excellent agreement with real prostate weight of the surgical specimens. Prostate volume measured by magnetic resonance has been increasingly used in the clinical practice, and its value enables appropriate therapeutic planning and control of patients.