Peripheral Zone Of Prostate Research Articles

Tale of two zones: investigating the clinical outcomes and research gaps in peripheral and transition zone prostate cancer through a systematic review and meta-analysis

ObjectiveTo assess pathological characteristics, clinical features and outcomes of patients diagnosed with peripheral zone (PZ) and transition zone (TZ) prostate cancer after prostatectomy.Methods and analysisWe systematically reviewed PubMed, EMBASE and...

High-resolution prostate diffusion MRI using eddy current-nulled convex optimized diffusion encoding and random matrix theory-based denoising.

To develop and evaluate a technique combining eddy current-nulled convex optimized diffusion encoding (ENCODE) with random matrix theory (RMT)-based denoising to accelerate and improve the apparent signal-to-noise ratio (aSNR) and apparent diffusion coefficient (ADC) mapping in high-resolution prostate diffusion-weighted MRI (DWI). MATERIALS ANDMETHODS: Eleven subjects with clinical suspicion of prostate cancer were scanned at 3T with high-resolution (HR) (in-plane: 1.0 × 1.0 mm2) ENCODE and standard-resolution (1.6 × 2.2 mm2) bipolar DWI sequences (both had 7 repetitions for averaging, acquisition time [TA] of 5 min 50 s). HR-ENCODE was retrospectively analyzed using three repetitions (accelerated effective TA of 2 min 30 s). The RMT-based denoising pipeline utilized complex DWI signals and Marchenko-Pastur distribution-based principal component analysis to remove additive Gaussian noise in images from multiple coils, b-values, diffusion encoding directions, and repetitions. HR-ENCODE with RMT-based denoising (HR-ENCODE-RMT) was compared with HR-ENCODE in terms of aSNR in prostate peripheral zone (PZ) and transition zone (TZ). Precision and accuracy of ADC were evaluated by the coefficient of variation (CoV) between repeated measurements and mean difference (MD) compared to the bipolar ADC reference, respectively. Differences were compared using two-sided Wilcoxon signed-rank tests (P < 0.05 considered significant). HR-ENCODE-RMT yielded 62% and 56% higher median aSNR than HR-ENCODE (b = 800 s/mm2) in PZ and TZ, respectively (P < 0.001). HR-ENCODE-RMT achieved 63% and 70% lower ADC-CoV than HR-ENCODE in PZ and TZ, respectively (P < 0.001). HR-ENCODE-RMT ADC and bipolar ADC had low MD of 22.7 × 10-6 mm2/s in PZ and low MD of 90.5 × 10-6 mm2/s in TZ. HR-ENCODE-RMT can shorten the acquisition time and improve the aSNR of high-resolution prostate DWI and achieve accurate and precise ADC measurements in the prostate.

Computerized metric assessment of glandular tissue volume within the peripheral zone of the prostate using combined magnetic resonance imaging and histopathology: Possible pathophysiological implications on prostate cancer development.

Benign prostatic hyperplasia (BPH) and prostate cancer (PCa) are prevalent urological ailments in elderly males. Numerous clinical studies have revealed an invert association between BPH/prostate size and PCa growth. This study investigates the association between prostate size and total glandular tissue volume of the peripheral zone (GVPZ) using a unique blend of magnetic resonance imaging (MRI) and histo-anatomical imaging technique. Patients were selected who underwent both radical prostatectomy and preoperative MRI scans. MRI scans provided quantitative measurements of prostatic zone dimensions, while histo-anatomical slides yielded quantitative data on glandular density of the peripheral zone (PZ) using imaging software. Integration of MRI and histopathology enabled the assessment of the GVPZ. Statistical analysis identified relationships between total prostate volume (TPV) and GVPZ. Seventy-two patients were selected and 40 cc was determined to be the optimal cutoff for small-to-moderate versus large prostates. Once the two subgroups in TPV were formed, the relationship between TPV and GVPZ was found to be highly significant (p<0.001). The combination of MRI and histopathology offers a novel approach for precise quantification of glandular tissue within the prostatic PZ. This study corroborates the hypothesis of PZ compression via an enlarging transition zone in larger BPH prostates, resulting in PZ glandular atrophy. Given that most PCa originates in the PZ, these results shed light on the potential protective role of larger BPH prostates against PCa growth.

Role of non-contrast CT component of prostate-specific membrane antigen PET/CT scan in the detection of peripheral zone prostate cancer.

The aim of this study was to look for feasibility of non-contrast CT (NCCT) in detecting peripheral zone prostate cancer (PCa). A retrospective analysis included 50 biopsy-proven PCa patients between April 2019 and March 2022 who underwent staging whole body prostate-specific membrane antigen (PSMA)/CT prior to treatment. The control subjects were 50 randomly selected adult male patients who underwent PET/CT for non-prostate malignancy during the same time period. Two readers independently calculated the Hounsfield unit (HU) of normal peripheral zone, central zone, and corresponding PSMA avid focus in cases. No significant difference was seen in the mean HU value of normal peripheral zone between cases and controls. Significant difference in the mean HU was seen between the PSMA avid focus in cases (40.1 ± 6.2) and normal peripheral zone of cases (28.2 ± 7.0) and controls (27.7 ± 5.8). No significant difference was found between the mean HU values of high-grade PCa and non-high-grade PCa. Receiver operating characteristic (ROC) curve analysis revealed a mean HU cut-off of ≥35 for detecting PCa with a sensitivity and specificity of 86% and 90%, respectively, between cases and controls (AUC 0.88). Detection of clinically significant PCa is possible on routinely performed NCCT scans. Radiologists should routinely look for and convey these findings to facilitate further work-up and early detection of PCa. Our study adds to the knowledge that NCCT scans performed for unrelated indications can serve as a screening tool for clinically significant PCa.

Machine learning based on radiomics features combing B-mode transrectal ultrasound and contrast-enhanced ultrasound to improve peripheral zone prostate cancer detection

PurposeTo construct machine learning models based on radiomics features combing conventional transrectal ultrasound (B-mode) and contrast-enhanced ultrasound (CEUS) to improve prostate cancer (PCa) detection in peripheral zone (PZ).MethodsA prospective study of 166 men (72 benign, 94 malignant lesions) with targeted biopsy-confirmed pathology who underwent B-mode and CEUS examinations was performed. Risk factors, including age, serum total prostate-specific antigen (tPSA), free PSA (fPSA), f/t PSA, prostate volume and prostate-specific antigen density (PSAD), were collected. Time-intensity curves were obtained using SonoLiver software for all lesions in regions of interest. Four parameters were collected as risk factors: the maximum intensity (IMAX), rise time (RT), time to peak (TTP), and mean transit time (MTT). Radiomics features were extracted from the target lesions from B-mode and CEUS imaging. Multivariable logistic regression analysis was used to construct the model.ResultsA total of 3306 features were extracted from seven categories. Finally, 32 features were screened out from radiomics models. Five models were developed to predict PCa: the B-mode radiomics model (B model), CEUS radiomics model (CEUS model), B-CEUS combined radiomics model (B-CEUS model), risk factors model, and risk factors-radiomics combined model (combined model). Age, PSAD, tPSA, and RT were significant independent predictors in discriminating benign and malignant PZ lesions (P < 0.05). The risk factors model combing these four predictors showed better discrimination in the validation cohort (area under the curve [AUC], 0.84) than the radiomics images (AUC, 0.79 on B model; AUC, 0.78 on CEUS model; AUC, 0.83 on B-CEUS model), and the combined model (AUC: 0.89) achieved the greatest predictive efficacy.ConclusionThe prediction model including B-mode and CEUS radiomics signatures and risk factors represents a promising diagnostic tool for PCa detection in PZ, which may contribute to clinical decision-making.

Human prostate MRI at ultrahigh-performance gradient: A feasibility study.

To demonstrate the technical feasibility and the value of ultrahigh-performance gradient in imaging the prostate in a 3T MRI system. In this local institutional review board-approved study, prostate MRI was performed on 4 healthy men. Each subject was scanned in a prototype 3T MRI system with a 42-cm inner-diameter gradient coil that achieves a maximum gradient amplitude of 200 mT/m and slew rate of 500 T/m/s. PI-RADS V2.1-compliant axial T2 -weighted anatomical imaging and single-shot echo planar DWI at standard gradient of 70 mT/m and 150 T/m/s were obtained, followed by DWI at maximum performance (i.e., 200 mT/m and 500 T/m/s). In comparison to state-of-the-art clinical whole-body MRI systems, the high slew rate improved echo spacing from 1020 to 596 μs and, together with a high gradient amplitude for diffusion encoding, TE was reduced from 55 to 36 ms. In all 4 subjects (waist circumference = 81-91 cm, age = 45-65 years), no peripheral nerve stimulation sensation was reported during DWI. Reduced image distortion in the posterior peripheral zone prostate gland and higher signal intensity, such as in the surrounding muscle of high-gradient DWI, werenoted. Human prostate MRI at simultaneously high gradient amplitude of 200 mT/m and slew rate of 500 T/m/s is feasible, demonstrating that improved gradient performance can address image distortion and T2 decay-induced SNR issues for in vivo prostate imaging.

Club-like cells in proliferative inflammatory atrophy of the prostate.

Club cells are a type of bronchiolar epithelial cell that serve a protective role in the lung and regenerate damaged lung epithelium. Single-cell RNA sequencing (scRNA-seq) of young adult human prostate and urethra identified cell populations in the prostatic urethra and collecting ducts similar in morphology and transcriptomic profile to lung club cells. We further identified club cell-like epithelial cells by scRNA-seq of prostate peripheral zone tissues. Here, we aimed to identify and spatially localize club cells in situ in the prostate, including in the peripheral zone. We performed chromogenic RNA in situ hybridization for five club cell markers (CP, LTF, MMP7, PIGR, SCGB1A1) in a series of (1) nondiseased organ donor prostate and (2) radical prostatectomy specimens from individuals with prostate cancer. We report that expression of club cell genes in the peripheral zone is associated with inflammation and limited to luminal epithelial cells classified as intermediate cells in proliferative inflammatory atrophy (PIA). Club-like cells were enriched in radical prostatectomy specimens compared to nondiseased prostates and associated with high-grade prostate cancer. We previously reported that luminal epithelial cells in PIA can rarely harbor oncogenic TMPRSS2:ERG (ERG+) gene fusions, and we now demonstrate that club cells are present in association with ERG+ PIA that is transitioning to early adenocarcinoma. Finally, prostate epithelial organoids derived from prostatectomy specimens demonstrate that club-like epithelial cells can be established in organoids and are sensitive to anti-androgen-directed treatment in vitro in terms of decreased androgen signaling gene expression signatures compared to basal or hillock cells. Overall, our study identifies a population of club-like cells in PIA and proposes that these cells play an analogous role to that of club cells in bronchiolar epithelium. Our results further suggest that inflammation drives lineage plasticity in the human prostate and that club cells in PIA may be prone to oncogenic transformation. © 2023 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.

Magnetic resonance fingerprinting based comprehensive quantification of T1 and T2 values of the background prostatic peripheral zone: Correlation with clinical and demographic features

PurposeTo quantify and assess the distribution of MR fingerprinting (MRF)-derived T1 and T2 values of the whole prostatic peripheral zone (PZ), and perform subgroup analyses according to clinical and demographic features. MethodOne hundred and twenty-four patients with prostate MR exams and MRF-based T1 and T2 maps of the prostatic apex, mid gland, and base were identified from our database and included. Regions of interest encompassing the right and left lobes of the PZ were drawn for each axial slice on the T2 map and copied to the T1 map. Clinical data were obtained from medical records. Kruskal-Wallis test was used for assessing differences between subgroups and the Spearman coefficient was used for assessing any correlations. ResultsMean T1 and T2 values were 1941 and 88 ms, respectively, for the whole-gland, 1884 and 83 ms for the apex, 1974 and 92 ms for the mid-gland, 1966 and 88 ms for the base. T1 values were weakly negatively correlated with PSA values, while T1 and T2 values were weakly positively correlated with prostate weight and moderately positively correlated with PZ width. Finally, patients with PI-RADS 1 scores had higher T1 and T2 values of the whole PZ, compared with those with scores 2–5. ConclusionMean T1 and T2 values of the background PZ of the whole gland were 1941 ± 313 and 88 ± 39 ms, respectively. Among clinical and demographic factors, there was a significant positive correlation between T1 and T2 values and PZ width.

Association between prostate size and glandular tissue volume of the peripheral zone via novel combined MRI and histopathology: possible pathophysiological implications on prostate cancer development.

Benign prostatic hyperplasia (BPH) and prostate cancer (PCa) are the two most prevalent urologic diseases affecting elderly men. An inverse relationship between BPH/prostate size and PCa incidence is well documented in the current literature, but the precise mechanism is poorly understood. This study aims to investigate the effect of total prostate volume on total glandular tissue volume of the peripheral zone via a novel combination of magnetic resonance imaging (MRI) and histo-anatomical imaging. 42 male patients between ages 53-79 years underwent both radical prostatectomy and pre-operative MRI scans. Prostate sizes ranged from 14.8-133.3cc. Quantitative measurements of surgical capsule thickness and glandular epithelial cell density within the peripheral zone (PZ) were obtained on histo-anatomical slides using computer-based imaging software. Quantitative prostatic zonal measurements were obtained from MRI scans. Combining MRI- and histopathology-obtained parameters allowed measurement of the total glandular tissue volume of the PZ (GVPZ). Statistical analysis was performed to identify associations between total prostate volume (TPV) and GVPZ. The Mann-Whitney U-test showed significant decreases in GVPZ in larger prostates when compared to smaller prostates. Combined MRI and histopathology techniques provide a novel method for accurate measuring of glandular tissue content within the prostatic PZ. The findings of this pilot study support the hypothesis of PZ compression by an expanding transition zone in large BPH prostates, leading to atrophy of PZ glandular tissue. As the majority of PCa originates in the PZ, this dynamic process may explain the protective effect of large BPH prostates against PCa development.

Correlation of multiparametric MRI with histopathological grade of peripheral zone prostate carcinoma.

Prostatic cancer is the second most common malignant tumor in men. Preoperative grading of prostate cancer is important for its management. Our objective is to compare individual and combined detection rates of T2-weighted imaging (T2WI), diffusion weighted imaging (DWI), dynamic contrast enhanced-magnetic resonance imaging (DCE-MRI), and magnetic resonance spectroscopy (MRS) for prostate cancer with histopathological diagnosis as its golden standard. Forty-four patients with positive digital rectal examination (DRE) findings and elevated prostate specific antigen (PSA), underwent multiparametric MRI (Mp-MRI). T2WI, DWI, DCE-MRI and MRS were done in all the patients. Cognitive magnetic resonance-transrectal ultrasound (MR-TRUS) fusion biopsy was done in all the patients. Sensitivity and specificity of T2WI, DWI, DCE-MRI, and Prostate Imaging - Reporting and Data System PIRADS version 2 was obtained. Apparent diffusion coefficient (ADC) value and choline/citrate ratio were obtained for each lesion and correlated with histopathological grade. The mean age of the patients was 68.7 ± 10.1 years, and the mean serum PSA level was 58.1 ± 22.4 ng/dL. Of the 38 lesions in peripheral zone, 33 (87%) had histopathologically proven prostate cancer. T2WI had a sensitivity and specificity of 75.8% and 80% and DWI had a sensitivity and specificity of 90.9% and 80%, respectively, for detection of malignant prostatic lesion. The mean ADC values for prostate cancer, prostatitis, and normal prostatic parenchyma were 0.702 ± 0.094 × 10-3 mm2/sec, 0.959 ± 0.171 × 10-3 mm2/sec, and 1.31 ± 0.223 × 10-3 mm2/sec, respectively. Type 3 curve has lower sensitivity (45.5%) but high specificity (80%) for diagnosing prostate cancer. DWI can be useful to differentiate benign from malignant prostatic lesions, and low-grade from high-grade prostate carcinoma. ADC value has a positive correlation with histopathological grade of prostate cancer.

Stromal FOXF2 suppresses prostate cancer progression and metastasis by enhancing antitumor immunity

Cancer-associated fibroblasts (CAFs) mediate an immunosuppressive effect, but the underlying mechanism remains incompletely defined. Here we show that increasing prostatic stromal Foxf2 suppresses the growth and progression of both syngeneic and autochthonous mouse prostate cancer models in an immunocompetent context. Mechanistically, Foxf2 moderately attenuates the CAF phenotype and transcriptionally downregulates Cxcl5, which diminish the immunosuppressive myeloid cells and enhance T cell cytotoxicity. Increasing prostatic stromal Foxf2 sensitizes prostate cancer to the immune checkpoint blockade therapies. Augmenting lung stromal Foxf2 also mediates an immunosuppressive milieu and inhibits lung colonization of prostate cancer. FOXF2 is expressed higher in the stroma of human transition zone (TZ) than peripheral zone (PZ) prostate. The stromal FOXF2 expression level in primary prostate cancers inversely correlates with the Gleason grade. Our study establishes Foxf2 as a stromal transcription factor modulating the tumor immune microenvironment and potentially explains why cancers are relatively rare and indolent in the TZ prostate.

Single-cell RNA-sequencing technology demonstrates the heterogeneity between aged prostate peripheral and transitional zone.

BackgroundIdentifying cellular and functional heterogeneity within aged prostate is critical for understanding the spatial distribution of prostate diseases.MethodsAged human prostate peripheral zone (PZ) and transitional zone (TZ) tissues were used for single‐cell RNA‐sequencing. Results were validated by immunofluorescence staining.ResultsWe found that club/hillock epithelial cells, compared with other epithelial cells, had significantly higher NOTCH signaling activity and expressed higher levels of neuro‐stems but lower androgen‐related genes. These cells were primarily found in the TZ and provided a stem‐like niche around the proximal prostate ducts. Significant heterogeneity was observed in the aged luminal population. A novel TFF3+ luminal subtype with elevated MYC and E2F pathway activities was observed, primarily in the PZ. Further analysis revealed that epithelial cells in the TZ had higher levels of stem‐ and inflammation‐related pathway activities but lower androgen/lineage‐related pathway activities than those in the PZ. Notably, the activation of MYC, E2F and DNA repair pathways significantly increased in PZ luminal cells. In the immune landscape, we found that the immune microenvironment in the TZ is more complex and disordered with more infiltration of NK and Treg cells. CD8 T cell and macrophage in the TZ exhibit both inflammation activation and suppression phenotypes. In the stroma, the TZ had a higher fibroblast density, and fibroblasts in the TZ exhibited stronger transcriptome activity in immunity and proliferation. Ligand–receptor interaction analysis revealed that fibroblasts could contribute to a NOTCH signaling niche for club/hillock cells in the TZ and balance the prostate immune microenvironment. The activation of stem properties, inflammatory infiltration and loss of androgen/lineage activity are prominent features distinguishing the TZ from PZ.ConclusionsOur study explains the heterogeneity between the TZ and PZ of aged prostate, which may help understand the spatial distribution of prostate diseases and establish a foundation for novel target discovery.

Reproducibility of apparent diffusion coefficient measurement in normal prostate peripheral zone at 1.5T MRI

PurposeThe purpose of this study was to quantify the influence of factors of variability on apparent diffusion coefficient (ADC) estimation in the normal prostate peripheral zone (PZ). Materials and methodsFifty healthy volunteers underwent in 2017 (n = 17) or 2020 (n = 33) two-point (0, 800 s/mm²) prostate diffusion-weighted imaging in the morning on 1.5 T scanners A and B from different manufacturers. Additional five-point (50, 150, 300, 500, 800 s/mm²) acquisitions were performed on scanner B in the morning and evening. ADC was measured in PZ at midgland using ADC maps reconstructed with various b-value combinations. ADC distributions from 2017 and 2020 were compared using Wilcoxon rank sum test. ADC obtained in the same volunteers were compared using Bland Altman methodology. The 95% confidence interval upper limit of the repeatability/reproducibility coefficient defined the lowest detectable ADC difference. ResultsForty-nine participants with a mean age of 24.6 ± 3.8 [SD] years (range: 21–37 years) were finally included. ADC distributions from 2017 and 2020 were not significantly different and were combined. Despite high individual variability, there was no significant bias (10 × 10−6 mm²/s, P = 0.58) between ADC measurements made on both scanners. On scanner B, differences in lowest b-values chosen within the 0–500 s/mm² range for two-point ADC computation induced significant biases (56-109 × 10−6 mm²/s, P < 0.0001). ADC was significantly lower in the morning (bias: 33 × 10−6 mm²/s, P = 0.006). The number of b-values had little influence on ADC values. The lowest detectable ADC difference varied from 85 × 10−6 to 311 × 10−6 mm²/s across scanners, b-value combinations and periods of the day. ConclusionsThe MRI scanner, the lowest b-value used and the period of the day induce substantial variability in ADC computation.

Usefulness of Collaborative Work in the Evaluation of Prostate Cancer from MRI.

The aim of this study is to show the usefulness of collaborative work in the evaluation of prostate cancer from T2-weighted MRI using a dedicated software tool. The variability of annotations on images of the prostate gland (central and peripheral zones as well as tumour) by two independent experts was firstly evaluated, and secondly compared with a consensus between these two experts. Using a prostate MRI database, experts drew regions of interest (ROIs) corresponding to healthy prostate (peripheral and central zones) and cancer. One of the experts then drew the ROI with knowledge of the other expert’s ROI. The surface area of each ROI was used to measure the Hausdorff distance and the Dice coefficient was measured from the respective contours. They were evaluated between the different experiments, taking the annotations of the second expert as the reference. The results showed that the significant differences between the two experts disappeared with collaborative work. To conclude, this study shows that collaborative work with a dedicated tool allows consensus between expertise in the evaluation of prostate cancer from T2-weighted MRI.

T1a/T1b transitional zone prostate cancer detection rates in patients who had TURP for clinically diagnosed benign prostatic enlargement in Southern Nigeria

Background: Transurethral resection of the prostate (TURP) removes the obstructing adenoma that grows from the transitional zone of the prostate. Resected chips are routinely sent for histologic examination. Incidental findings of prostate cancer in the TURP specimen for the clinically diagnosed benign disease may occur. The American Joint Committee on Cancer (AJCC) TNM staging of prostate cancer allocates T1a if &lt;5% of the resected chips are malignant and T1b if &gt;5% are malignant.&#x0D; Aim: To determine the frequency of incidental prostate cancer rate in TURP specimens of patients who had the procedure for clinically diagnosed benign prostatic enlargement.&#x0D; Methodology: This was a retrospective study carried out over a period of 8years from January 2013 to December 2020 on patients who had TURP for clinically diagnosed BPE or biopsy diagnosed BPH. All the patients had TURP for benign enlargements of the prostate. The resected prostate chips were sent for histopathological analysis. Patients with incomplete data and patients who had transrectal peripheral zone prostate biopsy confirmed cancers before TURP were excluded from this study. The data was collated using Microsoft Excel version 2020 and was analyzed using SPSS version 20.&#x0D; Results: There were 220 male patients with a mean age was 65.89 ±9.95years, and median age was 65years. The 60-69years group had the highest incidence of PCa. The T1a/T1b adenocarcinoma detection rate was 13.6% (30). 54.6% (120) had BPH only, and 31.8% (70) had BPH with prostatitis. All incidentally diagnosed T1a/T1b cancers were adenocarcinomas. The majority of the T1a/T1b adenocarcinomas, 43.3% (13), were poorly differentiated, while 36.7% (11) and 20% (6) had well and moderate differentiation, respectively.&#x0D; Conclusion: The Incidental T1a/T1b transitional zone adenocarcinoma detection rate in TURP specimens in the study was 13.6%. The high Gleason’s grade adenocarcinoma was the most frequent. Even when perceived as clinically benign, communication of the risk of cancer detection to the patient is pertinent and should be a routine part of the informed consenting process before TURP.

Multiparametric transrectal ultrasound for the diagnosis of peripheral zone prostate cancer and clinically significant prostate cancer: novel scoring systems

BackgroundTo evaluate the diagnostic performance of multiparametric transrectal ultrasound (TRUS) and to design diagnostic scoring systems based on four modes of TRUS to predict peripheral zone prostate cancer (PCa) and clinically significant prostate cancer (csPCa).MethodsA development cohort involved 124 nodules from 116 patients, and a validation cohort involved 72 nodules from 67 patients. Predictors for PCa and csPCa were extracted to construct PCa and csPCa models based on regression analysis of the development cohort. An external validation was performed to assess the performance of models using area under the curve (AUC). Then, PCa and csPCa diagnostic scoring systems were established to predict PCa and csPCa. The diagnostic accuracy was compared between PCa and csPCa scores and PI-RADS V2, using receiver operating characteristics (ROC) and decision curve analysis (DCA).ResultsRegression models were established as follows: PCa = − 8.284 + 4.674 × Margin + 1.707 × Adler grade + 3.072 × Enhancement patterns + 2.544 × SR; csPCa = − 7.201 + 2.680 × Margin + 2.583 × Enhancement patterns + 2.194 × SR. The PCa score ranged from 0 to 6 points, and the csPCa score ranged from 0 to 3 points. A PCa score of 5 or higher and a csPCa score of 3 had the greatest diagnostic performance. In the validation cohort, the AUC for the PCa score and PI-RADS V2 in diagnosing PCa were 0.879 (95% confidence interval [CI] 0.790–0.967) and 0.873 (95%CI 0.778–0.969). For the diagnosis of csPCa, the AUC for the csPCa score and PI-RADS V2 were 0.806 (95%CI 0.700–0.912) and 0.829 (95%CI 0.727–0.931).ConclusionsThe multiparametric TRUS diagnostic scoring systems permitted better identifications of peripheral zone PCa and csPCa, and their performances were comparable to that of PI-RADS V2.

Association of prostate size with capsule thickness and glandular epithelial cell density: The possible clinical implications on prostate cancer development

Objective: Benign prostatic hyperplasia (BPH) and prostate cancer (PCa) are the two most common urologic diseases in aging males. The negative association between prostate/BPH size and incidence of PCa is well documented in the literature. However, the exact mechanism is not well understood. This study aims to further investigate the possible effect of prostate volume on prostate capsule thickness and glandular cell density in the prostatic peripheral zone (PZ). Materials and Methods: A total of 100 patients were selected that had undergone radical prostatectomy with prostate sizes ranging from 20 to 160 mL. Quantitative measurements of capsule thickness and density of epithelial glands within the peripheral zone not affected by cancer were analysed and calculated on histo-anatomical slides using computer-based imaging software. Associations between the different variables were calculated using Spearman correlation with 95% confidence intervals (CIs). Results: In the non-cancerous areas of the PZ, prostate volume and average capsule thickness are positively associated ( rs = +0.6526, 95% CI +0.5233 to +0.7526, p &lt; 0.0001), while prostate volume and average glandular epithelial cell density of the PZ are negatively associated ( rs = −0.6011, 95% CI −0.7133 to −0.4589, p &lt; 0.0001). These associations remain consistent on subgroup analysis. Conclusion: The findings of this study support the hypothesis that transition zone (TZ) growth in large BPH prostates may cause pressure on the outer PZ, leading to fibrosis and atrophy of the glandular tissue. This may provide a protective effect against PCa, as most PCa originates in the PZ of the prostate. Level of evidence: Not applicable

Fully automated quantification of in vivo viscoelasticity of prostate zones using magnetic resonance elastography with Dense U-net segmentation

Magnetic resonance elastography (MRE) for measuring viscoelasticity heavily depends on proper tissue segmentation, especially in heterogeneous organs such as the prostate. Using trained network-based image segmentation, we investigated if MRE data suffice to extract anatomical and viscoelastic information for automatic tabulation of zonal mechanical properties of the prostate. Overall, 40 patients with benign prostatic hyperplasia (BPH) or prostate cancer (PCa) were examined with three magnetic resonance imaging (MRI) sequences: T2-weighted MRI (T2w), diffusion-weighted imaging (DWI), and MRE-based tomoelastography, yielding six independent sets of imaging data per patient (T2w, DWI, apparent diffusion coefficient, MRE magnitude, shear wave speed, and loss angle maps). Combinations of these data were used to train Dense U-nets with manually segmented masks of the entire prostate gland (PG), central zone (CZ), and peripheral zone (PZ) in 30 patients and to validate them in 10 patients. Dice score (DS), sensitivity, specificity, and Hausdorff distance were determined. We found that segmentation based on MRE magnitude maps alone (DS, PG: 0.93 ± 0.04, CZ: 0.95 ± 0.03, PZ: 0.77 ± 0.05) was more accurate than magnitude maps combined with T2w and DWI_b (DS, PG: 0.91 ± 0.04, CZ: 0.91 ± 0.06, PZ: 0.63 ± 0.16) or T2w alone (DS, PG: 0.92 ± 0.03, CZ: 0.91 ± 0.04, PZ: 0.65 ± 0.08). Automatically tabulated MRE values were not different from ground-truth values (P>0.05). In conclusion, MRE combined with Dense U-net segmentation allows tabulation of quantitative imaging markers without manual analysis and independent of other MRI sequences and can thus contribute to PCa detection and classification.

Is the Peripheral Zone Thickness an Indicator of a Learning Curve in Bipolar Transurethral Plasma Enucleation of the Prostate?-A Single Center Cohort Study.

BackgroundWe conducted this cohort study to assess the differences in the learning curve of bipolar transurethral plasma enucleation of the prostate (B-TUEP) associated with prostatic peripheral zone thickness (PZT) under MRI quantitative measurements.MethodsFor the study, 60 patients with benign prostatic hyperplasia (BPH) were involved. PZT are defined as “Thin” (<7 mm), “Thick” (>10 mm), and “Medium” (in between), with 20 patients in each group. Learning stages were defined as Group 1 (No. 1–20), Group 2 (No. 21–40), and Group 3 (No. 41–60). We measured parameters of the prostate, such as PZT and transitional zone thickness (TZT), with MRI. A learner with no experience in enucleation performed the operations. Statistical analyses were performed to compare the differences. Pearson correlation analysis and multiple linear regression analysis evaluated the relationship between characteristics of patients. P < 0.05 was deemed statistically significant.ResultsOne-Way ANOVA revealed different enucleation efficiency (0.811 ± 0.18 vs. 0.748 ± 0.14 vs. 0.634 ± 0.16), prostate volume (58.9 ± 15.33 vs. 57.3 ± 15.58 vs. 46.6 ± 14.10), and thickness of transition zone (44.45 ± 7.60 vs. 42.45 ± 6.08 vs. 34.78 ± 6.04) among Thin, Medium, and Thick groups. The enucleation efficiency is different between groups divided by learning stages (Group 1 vs. Group 3, 0.658 vs. 0.783; Group 2 vs. Group 3, 0.751 vs. 0.783). Pearson correlation analysis reveals that PZT was negatively correlated with prostate volume (r = −0.427), resection weight (r = −0.35), enucleation efficiency (r = −0.445), and TZT (r = −0.533), and was positively correlated with Q-max (r = 0.301) and bladder outlet obstruction index (BOOI) (r = 0.388). The regression coefficients of PZT, TZT, prostate volume, and Q-max were −0.012, 0.008, 0.007, and 0.013, respectively (all P < 0.05).ConclusionLower PZT is independent of higher enucleation efficiency, larger adenoma, and higher TZT. PZT may be an important factor on the learning curve of B-TUEP. Higher TZT, prostate volume. and Q-max may also relate to higher enucleation efficiency. For B-TUEP learners, it seems easier to perform the operation when the PZT is low, though more care should be taken with the capsule perforation. Further, the capsule plane should be maintained more attentively if the PZT is high.

DWI-related texture analysis for prostate cancer: differences in correlation with histological aggressiveness and data repeatability between peripheral and transition zones

BackgroundWe investigated the correlation between texture features extracted from apparent diffusion coefficient (ADC) maps or diffusion-weighted images (DWIs), and grade group (GG) in the prostate peripheral zone (PZ) and transition zone (TZ), and assessed reliability in repeated examinations.MethodsPatients underwent 3-T pelvic magnetic resonance imaging (MRI) before radical prostatectomy with repeated DWI using b-values of 0, 100, 1,000, and 1,500 s/mm2. Region of interest (ROI) for cancer was assigned to the first and second DWI acquisition separately. Texture features of ROIs were extracted from comma-separated values (CSV) data of ADC maps generated from several sets of two b-value combinations and DWIs, and correlation with GG, discrimination ability between GG of 1–2 versus 3–5, and data repeatability were evaluated in PZ and TZ.ResultsForty-four patients with 49 prostate cancers met the eligibility criteria. In PZ, ADC 10% and 25% based on ADC map of two b-value combinations of 100 and 1,500 s/mm2 and 10% based on ADC map with b-value of 0 and 1,500 s/mm2 showed significant correlation with GG, acceptable discrimination ability, and good repeatability. In TZ, higher-order texture feature of busyness extracted from ADC map of 100 and 1,500 s/mm2, and high gray-level run emphasis, short-run high gray-level emphasis, and high gray-level zone emphasis from DWI with b-value of 100 s/mm2 demonstrated significant correlation, excellent discrimination ability, but moderate repeatability.ConclusionsSome DWI-related features showed significant correlation with GG, acceptable to excellent discrimination ability, and moderate to good data repeatability in prostate cancer, and differed between PZ and TZ.