The Impact of Prostate Volume on Prostate Cancer Detection: Comparing Magnetic Resonance Imaging with Transrectal Ultrasound in Biopsy-naïve Men

Background and objective

This study aimed to determine the difference in prostate volume (PV) derived from transrectal ultrasound (TRUS) and multiparametric magnetic resonance imaging (mpMRI), and to further investigate the role of TRUS prostate-specific antigen density (PSAD) and mpMRI-PSAD in prostate cancer (PCa) detection in biopsy-naïve men.

Methods

Patients who underwent an initial prostate biopsy within 3 mo after mpMRI between January 2016 and December 2021 were analyzed retrospectively. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of both TRUS-PSAD and mpMRI-PSAD for PCa detection were calculated and compared. The Pearson correlation coefficient, Bland-Altman plot, and receiver operating characteristic curve were also utilized to explore the interests of this study.

Key findings and limitations

The median prostate-specific antigen level of 875 patients was 9.79 (interquartile range [IQR]: 7.09-13.50) ng/ml. The median mpMRI-PV and TRUS-PV were 41.92 (IQR: 29.29-60.73) and 41.04 (IQR: 29.24-57.27) ml, respectively, demonstrating a strong linear correlation (r = 0.831, 95% confidence interval: 0.809, 0.850; p < 0.01) and sufficient agreement. No significant difference was observed in terms of the sensitivity, specificity, PPV, and NPV between TRUS-PSAD and mpMRI-PSAD for any PCa and clinically significant PCa (csPCa) detection. The overall discriminative ability of TRUS-PSAD for detecting PCa or non-PCa, as well as csPCa and non-csPCa, was comparable with that of mpMRI-PSAD, and similar results were also observed in the subsequent analysis stratified by mpMRI-PV quartiles, prostate-specific antigen level, and age. The limitations include the retrospective and single-center nature and a lack of follow-up information.

Conclusions and clinical implications

TRUS-PV and MRI-PV exhibited a strong linear correlation and reached sufficient agreement. The efficiency of TRUS-PSAD and mpMRI-PSAD for PCa detection was comparable. TRUS could be used for PV estimation and dynamic monitoring of PSAD, and TRUS-PSAD could effectively guide clinical decision-making and optimize diagnostic strategies.

Patient summary

In this work, prostate volume (PV) derived from transrectal ultrasound (TRUS) exhibited a strong linear correlation with the PV derived from multiparametric magnetic resonance imaging (mpMRI). The efficiency of TRUS prostate-specific antigen density (PSAD) and mpMRI-PSAD for the detection of prostate cancer was comparable. TRUS could be used for PV estimation and TRUS-PSAD could help in clinical decision-making and optimizing diagnostic strategies.

The Role of Digital Rectal Examination Prostate Volume Category in the Early Detection of Prostate Cancer: Its Correlation with the Magnetic Resonance Imaging Prostate Volume

PURPOSE

To relate the prostate volume category (PVC) assessed with digital rectal examination (DRE)-small, median, and large-and the prostate volumes (PVs) assessed with magnetic resonance imaging (MRI) and transrectal ultrasound (TRUS). To compare the clinically significant prostate cancer (csPCa) discrimination ability of two predictive models based on DRE-PVC and MRI-PV.

MATERIALS AND METHODS

A prospective trial of 2,090 men with prostate-specific antigen >3 ng/mL and/or PCa suspicious DRE were prospectively recruited in 10 centers from Catalonia (Spain), between 2021 and 2022, in whom DRE-PVC was assessed. Pre-biopsy MRI, and 12-core TRUS-random biopsy was always performed after 2- to 6-core TRUS-fusion targeted biopsy of prostate imaging-report and data system >3 lesions. In 370 men (17.7%) the DRE-PVC was unconclusive. Among the 1,720 men finally analyzed the csPCa (grade group >2) detection was 42.4%.

RESULTS

The median (interquartile range) of TRUS and MRI-PVs of small prostates were 33 mL (19-37 mL) and 35 mL (23-30 mL), p=0.410; in median prostates they were 51 mL (38-58 mL) and 55 mL (48-63 mL) respectively, p<0.001; in large prostates 80 mL (60-100 mL) and 95 mL (75-118 mL) respectively, p<0.001. The predictive models sharing the MRI-PV and DRE-PVC showed areas under the curves of 0.832 (95% confidence interval [CI], 0.813-0.851) and 0.828 (95% CI, 0.809-0.848) respectively, p=0.632, as well as similar net benefit and clinical utility.

CONCLUSIONS

PVC was unconclusive in 17% of DREs. MRI-PV overestimated the TRUS-PV in median and large prostates. The predictive models based on MRI-PV and DRE-PVC showed similar efficacy to predict csPCa. PVC assessed with DRE is helpful to predict the csPCa risk before MRI.

Construction of machine learning models based on transrectal ultrasound combined with contrast-enhanced ultrasound to predict preoperative regional lymph node metastasis of rectal cancer

Purpose

Constructing a machine learning model based on transrectal ultrasound (TRUS) combined with contrast-enhanced ultrasound (CEUS) to predict preoperative regional lymph node metastasis (RLNM) of rectal cancer and provide new references for decision-making.

Materials and methods

233 patients with rectal cancer were enrolled and underwent TRUS and CEUS prior to surgery. Clinicopathological and ultrasound data were collected to analyze the correlation of RLNM status, clinical features and ultrasound parameters. A 75% training set and 25% test set were utilized to construct seven machine learning algorithms. The DeLong test was used to assess the model's diagnostic performance, then chose the best one to predict RLNM of rectal cancer.

Results

The diagnostic performance was most dependent on the following: MMT difference (36), length (30), location (29), AUC ratio (27), and PI ratio (24). The prediction accuracy, sensitivity, specificity, precision, and F1 score range of KNN, Bayes, MLP, LR, SVM, RF, and LightGBM were (0.553-0.857), (0.000-0.935), (0.600-1.000), (0.557-0.952), and (0.617-0.852), respectively. The LightGBM model exhibited the optimal accuracy (0.857) and F1 score (0.852). The AUC for machine learning analytics were (0.517-0.941, 95% CI: 0.380-0.986). The LightGBM model exhibited the highest AUC (0.941, 95% CI: 0.843-0.986), though no statistic significant showed in comparison with the SVM, LR, RF, and MLP models (P > 0.05), it was significantly higher than that of the KNN and Bayes models (P < 0.05).

Conclusion

The LightGBM machine learning model based on TRUS combined with CEUS may help predict RLNM prior to surgery and provide new references for clinical treatment in rectal cancer.

Transvaginal approach combined intracavitary and interstitial brachytherapy assisted by transrectal ultrasound: results from 30 patients with locally advanced cervical cancer

PURPOSE

This study evaluated the efficacy and safety of transvaginal approach combined intracavitary and interstitial brachytherapy (IC/IS BT) assisted by transrectal ultrasound (TRUS) for treatment of locally advanced cervical cancer (LACC).

MATERIALS AND METHODS

A total of 30 patients of LACC treated with external beam radiotherapy and IC/IS BT via transvaginal approach assisted by transrectal ultrasound were observed retrospectively. The 2-year local control (LC), progression-free survival (PFS), and overall survival (OS) were analyzed using the Kaplan-Meier method. Late adverse events were also evaluated to assess the safety of IC/IS BT.

RESULTS

The median follow-up period was 22 months. The 2-year LC, PFS, and OS were 90%, 61%, and 82%, respectively. We observed no critical complications related to the IC/IS BT technique. Late adverse events of grade 3 or more included one case of grade 4 colon perforation.

CONCLUSION

Our patient series demonstrated that radiotherapy combined with transvaginal approach, TRUS-assisted IC/IS BT achieves favorable local control and safety for LACC.

The diagnostic accuracy of micro-ultrasound for prostate cancer diagnosis: a review

PURPOSE

Micro-UltraSound (microUS) is a new imaging modality capable of identifying and targeting suspicious areas, which might further increase the diagnostic yield of prostate biopsy (PBx). Aim of this review is to provide insights into the usefulness of microUS for the sub-stratification of prostate cancer (PCa), clinically significant PCa (i.e., any Gleason score ≥ 7 PCa; csPCa) along with non-organ-confined disease in patients undergoing PBx.

METHODS

A PubMed literature search was performed using keywords: prostate cancer diagnosis, prostate cancer diagnosis surveillance, systematic biopsy, target biopsy, micro-ultrasound, and prostate risk identification using micro-ultrasound.

RESULTS

MicroUS could significantly improve multiparametric magnetic resonance imaging (mpMRI) findings by adding valuable anatomical and pathological information provided by real-time examination. Furthermore, microUS target biopsy could replace systematic biopsy in clinical practice by reducing the detection of clinically insignificant (ciPCa) and increasing that of csPCa. Finally, microUS may be useful in predicting the presence of non-organ confined PCa before radical prostatectomy and it could also be an effective add-on tool for patient monitoring within the active surveillance program.

CONCLUSION

MicroUS may represent an attractive step forward for the management of csPCa as a complementary or alternative tool to mpMRI. Nevertheless, further longitudinal studies are warranted, and the strength of the evidence is still suboptimal to provide clear recommendations for daily clinical practice.

Clinical and prostate multiparametric magnetic resonance imaging findings as predictors of general and clinically significant prostate cancer risk: A retrospective single-center study

Background

To evaluate the predictive values of Prostate Imaging Reporting and Data System version 2 (PI-RADS v2), prostate-specific antigen (PSA) level, PSA density (PSAD), digital rectal examination findings, and prostate volume, individually and in combination, for the detection of prostate cancer (PCa) in biopsy-naive patients.

Methods

We retrospectively analyzed 630 patients who underwent transrectal systematic prostate biopsy following prostate multiparametric magnetic resonance imaging. A standard 12-core biopsy procedure was performed. Univariate and multivariate analyses were performed to determine the significant predictors of clinically significant cancer but not PCa.

Results

The median age, PSA level, and PSAD were 70 years, 8.6 ng/mL, and 0.18 ng/mL/mL, respectively. A total of 374 (59.4%) of 630 patients were biopsy-positive for PCa, and 241 (64.4%) of 374 were diagnosed with clinically significant PCa (csPCa). The PI-RADS v2 score and PSAD were independent predictors of PCa and csPCa. The PI-RADS v2 score of 5 regardless of the PSAD value, or PI-RADS v2 score of 4 plus a PSAD of <0.3 ng/mL/mL, was associated with the highest csPCa detection rate (36.1%-82.1%). Instead, the PI-RADS v2 score of <3 and PSAD of <0.3 ng/mL/mL yielded the lowest risk of csPCa.

Conclusion

The combination of the PI-RADS v2 score and PSAD could prove to be a helpful and reliable diagnostic tool before performing prostate biopsies. Patients with a PI-RADS v2 score of <3 and PSAD of <0.3 ng/mL/mL could potentially avoid a prostate biopsy.

Value of contrast-enhanced ultrasound in deep angiomyxoma using a biplane transrectal probe: A case report

BACKGROUND

Deep angiomyxoma (DAM) is a very rare tumor type. Magnetic resonance imaging (MRI) is considered the best imaging modality for diagnosing DAM. Computed tomography (CT) is used mainly to assess the invasion range of DAM. The value of ultrasonography in the diagnosis of DAM is still controversial. Through a literature review, we summarized the current state of ultrasonic examination for DAM and reported for the first time the contrast-enhanced ultrasound (CEUS) features of DAM seen using a biplane transrectal probe.

CASE SUMMARY

A 37-year-old woman presented with a sacrococcygeal mass that had gradually increased in size over the previous 6 mo. MRI and CT examinations failed to allow a definite diagnosis to be made. Transperineal core needle biopsy (CNB) guided by transrectal ultrasound and CEUS was suggested after a multidisciplinary discussion. Grayscale ultrasound of the lesion showed a layered appearance with alternating hyperechoic and hypoechoic patterns. Transrectal CEUS showed a laminated distribution of the contrast agent that was consistent with the layered appearance of the tumor on grayscale ultrasound. We performed transperineal CNB of the enhanced area inside the tumor under transrectal CEUS guidance and finally made a definitive diagnosis of DAM through histopathology. The patient underwent laparoscopic-assisted transabdominal surgery combined with transperineal surgery for large pelvic tumor resection and pelvic floor peritoneal reconstruction. No recurrence or metastasis was found at the nine-month follow-up.

CONCLUSION

Transrectal CEUS can show the layered perfusion characteristics of the contrast agent, guiding subsequent transperineal CNB of the enhanced area within the DAM.

The significance of transrectal ultrasound and urologist_dually guided pelvic floor muscle exercise in improving urinary continence after radical prostatectomy

BACKGROUND

To determine whether transrectal ultrasound and urologist_dually guided pelvic floor muscle exercise is associated with immediate, early and long-term urinary continence after radical prostatectomy.

MATERIALS AND METHODS

Data from 114 patients with localized prostate cancer (PC) who underwent RP at Henan Cancer Hospital from November 2018 to April 2021 were included in the retrospective study. Of the 114 patients, 50 patients in the observation group underwent transrectal ultrasound and urologist_dually guided PFME, and 64 patients in the control group underwent verbally_guided PFME. Contractile function of the external urinary sphincter was in the observation group was evaluated. The immediate, early and long-term urinary continence rates were assessed in both groups, and the factors affecting urinary continence were analyzed.

RESULTS

The urinary continence rate at 2 weeks and 1, 3, 6 and 12 months in the observation group after RP was significantly higher than that in the control group (52.0% vs. 29.7%, 70.0% vs. 39.1%, 82% vs. 57.8, 88% vs. 70.3%, 98.0 vs. 84.4%, p < 0.05). The contractile function of the external urinary sphincter was obviously correlated with urinary continence at multiple visits after RP, except for the 12-month visit. Transrectal ultrasound and urologist-dually guided PFME was verified to be an independent positive factor for urinary continence at 2 weeks and 1, 3, 6 and 12 months using logistic regression analysis. However, TURP was a negative factor for postoperative urinary continence at different times.

CONCLUSIONS

Transrectal ultrasound and urologist_dually guided PFME had a significant role in improving immediate, early and long-term urinary continence after RP and acted as an independent prognostic factor.

Synthetic radial aperture focusing to regulate manual volumetric scanning for economic transrectal ultrasound imaging

In this paper, we present a volumetric transrectal ultrasound (TRUS) imaging under the presence of radial scanning angle disorientation (SAD) in a resource-limited diagnostic setting. Herein, we test our hypothesis that a synthetic radial aperture focusing (TRUS-rSAF) technique, in which a radial plane in target volume is reconstructed by coherent compounding of multiple transmittance/reception events, will reject a randomized SAD in a free-hand scanning setup based on external angular tracking. Based on an analytical model of the TRUS-rSAF technique, we first tested specific scenarios using a clinically available TRUS transducer under different SADs in a range of normal distributions (σ = 0.1°, 0.2°, 0.5°, 1°, 2°, and 5°). We found a benefit of the TRUS-rSAF technique for higher robustness when the SAD is contained within the radial synthetic aperture window, i.e., ±0.71° from a target scanning angle. However, no enhancement was found in spatial resolution because of the limited transmit beam field of the clinical TRUS transducer, limiting the synthetic aperture window. We further evaluated the TRUS-rSAF technique with a modified TRUS transducer for an extended synthetic aperture window to test whether higher spatial resolution and robustness to SAD can be obtained in the same evaluation setup. Widening of the synthetic aperture window (±3.54°, ± 5.91°, ± 8.27°, ± 10.63°, ± 12.99°, ± 15.35°) resulted in proportional enhancements of spatial resolution, but it also progressively built up sidelobe artifacts due to randomized synthesis with limited phase cancellations. The results suggest the need for careful calibration of the TRUS-rSAF technique to enable TRUS imaging with free-hand radial scanning and external angle tracking in resource-limited settings.

Detection of Clinically Significant Prostate Cancer Using Targeted Biopsy with Four Cores Versus Target Saturation Biopsy with Nine Cores in Transperineal Prostate Fusion Biopsy: A Prospective Randomized Trial

BACKGROUND

Multiparametric magnetic resonance imaging (mpMRI) and targeted biopsy (TB) facilitate accurate detection of clinically significant prostate cancer (csPC). However, it remains unclear how targeted cores should be applied for accurate diagnosis of csPC.

OBJECTIVE

To assess csPC detection rates for two target-directed MRI/transrectal ultrasonography (TRUS) fusion biopsy approaches, conventional TB and target saturation biopsy (TS).

DESIGN, SETTING, AND PARTICIPANTS

This was a prospective single-center study of outcomes for transperineal MRI/TRUS fusion biopsies for 170 men. Half of the men (n = 85) were randomized to conventional TB with four cores per lesion and half (n = 85) to TS with nine cores. Biopsies were performed by three experienced board-certified urologists.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

PC and csPC (International Society of Urological Pathology grade group ≥2) detection rates for systematic biopsy (SB), TB, and TS were analyzed using McNemar's test for intrapatient comparisons and Fisher's exact test for TS versus TB. A combination of targeted biopsy (TS or TB) and SB served as the reference.

RESULTS AND LIMITATIONS

According to the reference, csPC was diagnosed for 57 men in the TS group and 36 men in the TB group. Of these, TS detected 57/57 csPC cases and TB detected 33/36 csPC cases (p = 0.058). Detection of Gleason grade group 1 disease was 10/12 cases with TS and 8/17 cases with TB (p = 0.055). In addition, TS detected 97% of 63 csPC lesions, compared to 86% with TB (p = 0.1). Limitations include the single-center design, the limited generalizability owing to the transperineal biopsy route, the lack of central review of pathology and radical prostatectomy correlation, and uneven distributions of csPC prevalence, Prostate Imaging-Reporting and Data System (PI-RADS) 5 lesions, men with two or more PI-RADS ≥3 lesions, and prostate-specific antigen density between the groups, which may have affected the results.

CONCLUSIONS

In our study, rates of csPC detection did not significantly differ between TS and TB.

PATIENT SUMMARY

In this study, we investigated two targeted approaches for taking prostate biopsy samples after observation of suspicious lesions on prostate scans. We found that the rates of detection of prostate cancer did not significantly differ between the two approaches.

Domain generalization for prostate segmentation in transrectal ultrasound images: A multi-center study

Prostate biopsy and image-guided treatment procedures are often performed under the guidance of ultrasound fused with magnetic resonance images (MRI). Accurate image fusion relies on accurate segmentation of the prostate on ultrasound images. Yet, the reduced signal-to-noise ratio and artifacts (e.g., speckle and shadowing) in ultrasound images limit the performance of automated prostate segmentation techniques and generalizing these methods to new image domains is inherently difficult. In this study, we address these challenges by introducing a novel 2.5D deep neural network for prostate segmentation on ultrasound images. Our approach addresses the limitations of transfer learning and finetuning methods (i.e., drop in performance on the original training data when the model weights are updated) by combining a supervised domain adaptation technique and a knowledge distillation loss. The knowledge distillation loss allows the preservation of previously learned knowledge and reduces the performance drop after model finetuning on new datasets. Furthermore, our approach relies on an attention module that considers model feature positioning information to improve the segmentation accuracy. We trained our model on 764 subjects from one institution and finetuned our model using only ten subjects from subsequent institutions. We analyzed the performance of our method on three large datasets encompassing 2067 subjects from three different institutions. Our method achieved an average Dice Similarity Coefficient (Dice) of 94.0±0.03 and Hausdorff Distance (HD95) of 2.28 mm in an independent set of subjects from the first institution. Moreover, our model generalized well in the studies from the other two institutions (Dice: 91.0±0.03; HD95: 3.7 mm and Dice: 82.0±0.03; HD95: 7.1 mm). We introduced an approach that successfully segmented the prostate on ultrasound images in a multi-center study, suggesting its clinical potential to facilitate the accurate fusion of ultrasound and MRI images to drive biopsy and image-guided treatments.

The evolving role of contrast-enhanced ultrasound in urology: a review

PURPOSE

Ultrasound's versatility and ease of use has expanded its application in many clinical settings. Technological advancements with contrast-enhanced ultrasound (CEUS) have allowed high quality imaging similar to CT or MRI with lower risk of contrast toxicity and radiation exposure. In this review article we examine the development of CEUS and its vast applications in the field of urology.

METHODS

A PubMed literature search was performed using keywords: contrast enhanced ultrasound, prostate cancer, renal cancer, and multiparametric ultrasound.

RESULTS

The development of CEUS has improved transrectal ultrasound imaging with increased detection of prostate cancer (PCa). Further enhancements of CEUS such as subharmonic imaging (SHI), flash replenishment imaging (FRI) and contrast ultrasound dispersion imaging (CUDI) allow improved PCa diagnosis. CEUS has also emerged as an important tool in characterizing suspicious renal mass without compromising renal function with contrast imaging.

CONCLUSION

CEUS has modernized imaging and diagnosis of prostate and renal cancer. Future advancements and utilization of CEUS will allow its expansion into other urological subspecialties.

Contrast-Specific Spherical Lesion Phantoms and Ancillary Analysis Software for the Objective Evaluation of Transrectal Ultrasound System Contrast Detectability

Brachytherapy is an efficacious treatment option because of its benefits for patient recovery, dose localization and conformity, but these favorable outcomes can be ensured only if the transrectal ultrasound (TRUS) system is optimized for the specific application of ultrasound-guided prostate brachytherapy. The ability to delineate the prostate from surrounding tissue during TRUS-guided prostate brachytherapy is vital for treatment planning, and consequently, so is the contrast resolution. This study describes the development of task-specific contrast-detail phantoms with clinically relevant contrast and spherical target sizes for contrast-detail performance evaluation of TRUS systems used in the brachytherapy procedure. The procedure for objective assessment of the contrast detectability of the TRUS systems is also described; a program was developed in MATLAB (R2017a, The MathWorks, Natick, MA, USA) to quantitatively analyze image quality in terms of the lesion signal-to-noise ratio (LSNR) and validated with representative control test images. The LSNR of the Hitachi EUB-7500A (2013, Hitachi, Ltd, Tokyo, Japan) TRUS system was measured on sagittal and transverse TRUS images of the contrast-detail phantoms described in this work. Results revealed the efficacy of the device as an image quality evaluation tool and the impact of the size, depth and relative contrast of the targets to the surrounding tissue on the contrast detectability of a TRUS system for both transducer arrays. The MATLAB program objectively measured the contrast detectability of the TRUS system and has the potential to determine optimized imaging parameters that could be designed as part of standardization of the imaging protocol used in TRUS-guided prostate brachytherapy for prostate cancer.

Detection of clinically significant index prostate cancer using micro-ultrasound: correlation with radical prostatectomy

OBJECTIVE

To determine the detection of clinically significant prostate cancer (csPCa) index lesion using high resolution transrectal micro-ultrasound (MicroUS) applying PRI-MUS (Prostate Risk Identification using Micro Ultrasound) score v1.0.

METHODS

Men who underwent radical prostatectomy following biopsy and MicroUS assessment were included. MicroUS dynamic cine loops of these patients were retrospectively reviewed by an experienced radiologist. The radiologist was aware that patients had undergone radical prostatectomy but was blinded to pathological data. Suspicious sites were assigned a PRI-MUS score. Radical prostatectomy specimens were examined with quarter mount technique. Detection rate of csPCa index lesion [Grade Group (GG) ≥2] by MicroUS was assessed at a patient level.

RESULTS

Twenty-five participants were included in the analysis. The median age was 65.5 years (range 56 - 74). Median PSA was 6.45 ng/dL (range 2 - 31.72). Two of 25 patients did not have csPCa (GG1 disease) on radical prostatectomy. MicroUS visualized 20/23 (87%) of the csPCa index lesions [median length 9 mm (range 1.5- 28.5)]. All identified lesions were categorized PRIMUS score 4 or 5. The 3 missed index lesions were in the transition zone [median length 10.5 mm (range 4.5-22.5)]. MicroUS missed 11 non index csPCa in 9 participants [median length 1.5 mm (range 1.5-10.5)]. Of these, 8 were GG2, two GG3 and one GG5. MicroUS identified the csPCa index lesion in all 9 of these men.

CONCLUSION

MicroUS showed high sensitivity (87%) in detecting index lesions in the prostate gland and identified 100% of index lesions in the peripheral zone.

H-ProSeg: Hybrid ultrasound prostate segmentation based on explainability-guided mathematical model

BACKGROUND AND OBJECTIVE

Accurate and robust prostate segmentation in transrectal ultrasound (TRUS) images is of great interest for image-guided prostate interventions and prostate cancer diagnosis. However, it remains a challenging task for various reasons, including a missing or ambiguous boundary between the prostate and surrounding tissues, the presence of shadow artifacts, intra-prostate intensity heterogeneity, and anatomical variations.

METHODS

Here, we present a hybrid method for prostate segmentation (H-ProSeg) in TRUS images, using a small number of radiologist-defined seed points as the prior points. This method consists of three subnetworks. The first subnetwork uses an improved principal curve-based model to obtain data sequences consisting of seed points and their corresponding projection index. The second subnetwork uses an improved differential evolution-based artificial neural network for training to decrease the model error. The third subnetwork uses the parameters of the artificial neural network to explain the smooth mathematical description of the prostate contour. The performance of the H-ProSeg method was assessed in 55 brachytherapy patients using Dice similarity coefficient (DSC), Jaccard similarity coefficient (Ω), and accuracy (ACC) values.

RESULTS

The H-ProSeg method achieved excellent segmentation accuracy, with DSC, Ω, and ACC values of 95.8%, 94.3%, and 95.4%, respectively. Meanwhile, the DSC, Ω, and ACC values of the proposed method were as high as 93.3%, 91.9%, and 93%, respectively, due to the influence of Gaussian noise (standard deviation of Gaussian function, σ = 50). Although the σ increased from 10 to 50, the DSC, Ω, and ACC values fluctuated by a maximum of approximately 2.5%, demonstrating the excellent robustness of our method.

CONCLUSIONS

Here, we present a hybrid method for accurate and robust prostate ultrasound image segmentation. The H-ProSeg method achieved superior performance compared with current state-of-the-art techniques. The knowledge of precise boundaries of the prostate is crucial for the conservation of risk structures. The proposed models have the potential to improve prostate cancer diagnosis and therapeutic outcomes.

Analysis of the cause of missed diagnosis in mpMRI/TRUS fusion-guided targeted prostate biopsy

Objectives

To investigate the causes of missed diagnosis in mpMRI/TRUS fusion-guided targeted prostate biopsy.

Methods

The clinical data of 759 patients who underwent transperineal prostate biopsy from March 2021 to June 2021 at Nanjing DrumTower Hospital were retrospectively analyzed. Twenty-one patients had MRI contraindications. Ultimately, 738 patients completed mpMRI/TRUS fusion-guided targeted prostate biopsy + 12-core transperineal systematic biopsy after mpMRI and PI-RADS scoring. The pathological diagnoses from targeted and systematic biopsy were compared to evaluate and analyze the reasons for missed diagnoses in targeted biopsy.

Results

A total of 388 prostate cancer patients were identified, including 37 (9%) missed diagnoses with targeted biopsy and 44 (11.34%) with systematic biopsy. Between the target biopsy missed diagnosis group and not missed diagnosis group, there was no significant difference in age (71.08 ± 7.11 vs. 71.80 ± 7.94), but PSA (13.63 ± 12.41 vs. 54.54 ± 177.25 ng/ml), prostate volume (61.82 ± 40.64 vs. 44.34 ± 25.07 cm³), PSAD (0.27 ± 0.28 vs. 1.07 ± 2.91), and ISUP grade [1(1) vs. 3(2)] were significantly different. The pathological results of the 37 targeted biopsy missed diagnoses were recompared with MRI: 21 prostate cancers were normal on MRI; 9 cancer areas were abnormal on MRI; and 7 cancer areas on MRI were PI-RADS 3.

Conclusions

Early prostate cancer, large prostate, effect of local anesthesia, doctor–patient cooperation, MRI diagnosis, and operator technology were possible factors for missed diagnosis in targeted biopsy. Improvements imaging technology, greater experience, and personalized biopsy may lead to an accurate pathological diagnosis.

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

Background

To 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).

Methods

A 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).

Results

Regression 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).

Conclusions

The 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.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12894-022-01013-8.

A Prospective Multicenter Comparison Study of Risk-adapted Ultrasound-directed and Magnetic Resonance Imaging-directed Diagnostic Pathways for Suspected Prostate Cancer in Biopsy-naïve Men

BACKGROUND

European Association of Urology guidelines recommend a risk-adjusted biopsy strategy for early detection of prostate cancer in biopsy-naïve men. It remains unclear which strategy is most effective. Therefore, we evaluated two risk assessment pathways commonly used in clinical practice.

OBJECTIVE

To compare the diagnostic performance of a risk-based ultrasound (US)-directed pathway (Rotterdam Prostate Cancer Risk Calculator [RPCRC] #3; US volume assessment) and a magnetic resonance imaging (MRI)-directed pathway.

DESIGN, SETTING, AND PARTICIPANTS

This was a prospective multicenter study (MR-PROPER) with 1:1 allocation among 21 centers (US arm in 11 centers, MRI arm in ten). Biopsy-naïve men with suspicion of prostate cancer (age ≥50 yr, prostate-specific antigen 3.0-50 ng/ml, ± abnormal digital rectal examination) were included.

INTERVENTION

Biopsy-naïve men with elevated risk of prostate cancer, determined using RPCRC#3 in the US arm and Prostate Imaging Reporting and Data System scores of 3-5 in the MRI arm, underwent systematic biopsies (US arm) or targeted biopsies (MRI arm).

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

The primary outcome was the proportion of men with grade group (GG) ≥2 cancer. Secondary outcomes were the proportions of biopsies avoided and GG 1 cancers detected. Categorical (nonparametric) data were assessed using the Mann-Whitney U test and χ² tests.

RESULTS AND LIMITATIONS

A total of 1965 men were included in the intention-to-treat population (US arm n = 950, MRI arm n = 1015). The US and MRI pathways detected GG ≥2 cancers equally well (235/950, 25% vs 239/1015, 24%; difference 1.2%, 95% confidence interval [CI] -2.6% to 5.0%; p = 0.5). The US pathway detected more GG 1 cancers than the MRI pathway (121/950, 13% vs 84/1015, 8.3%; difference 4.5%, 95% CI 1.8-7.2%; p < 0.01). The US pathway avoided fewer biopsies than the MRI pathway (403/950, 42% vs 559/1015, 55%; difference -13%, 95% CI -17% to -8.3%; p < 0.01). Among men with elevated risk, more GG ≥2 cancers were detected in the MRI group than in the US group (52% vs 43%; difference 9.2%, 95% CI 3.0-15%; p < 0.01).

CONCLUSIONS

Risk-adapted US-directed and MRI-directed pathways detected GG ≥2 cancers equally well. The risk-adapted US-directed pathway performs well for prostate cancer diagnosis if prostate MRI capacity and expertise are not available. If prostate MRI availability is sufficient, risk assessment should preferably be performed using MRI, as this avoids more biopsies and detects fewer cases of GG 1 cancer.

PATIENT SUMMARY

Among men with suspected prostate cancer, relevant cancers were equally well detected by risk-based pathways using either ultrasound or magnetic resonance imaging (MRI) to guide biopsy of the prostate. If prostate MRI availability is sufficient, risk assessment should be performed with MRI to reduce unnecessary biopsies and detect fewer irrelevant cancers.

[Sonography of the prostate : Relevance for urologists in daily clinical routine]

Despite the continuous technical progress regarding the transrectal ultrasonography of the prostate (TRUS) and its successful use in combination with magnetic resonance imaging (MRI) in MRI-targeted biopsy, there is no radiologic modality being able to rule out clinically significant prostate cancer without the need of systematic biopsy. In the past few years, TRUS regained more attention due to the development of high frequency ultrasound as well as the combination of different ultrasonic modalities like shear wave elastography and contrast-enhanced sonography (CEUS). Currently, multiparametric MRI (mpMRI)-targeted biopsy shows the best results concerning detection rates, sensitivity and specificity of clinically significant prostate cancer compared to systematic biopsy. In the future, transperineal biopsy is probably going to increasingly replace the transrectal biopsy approach. For both approaches, transrectal ultrasonography is necessary to display the prostate and to detect suspicious lesions. Therefore future improvements in transrectal ultrasonography can be expected.

Use of a novel anthropomorphic prostate simulator in a prostate brachytherapy transrectal ultrasound imaging workshop for medical physicists

PURPOSE

Ultrasound imaging training is not required as part of radiation oncology training programs nor does any objective competency measure exist to independently assess performance. Physical simulation training can provide a structured approach to this training but only if suitably challenging training simulators exist. This study describes the design and preliminary evaluation of a simulation-based transrectal ultrasound (TRUS) imaging training workshop developed for medical physicists involved in low-dose-rate (LDR) prostate brachytherapy (PBT).

METHODS

The study incorporated novel high-fidelity anthropomorphic PBT TRUS training simulators and a TRUS imaging module with a blended-learning pedagogical approach, to address TRUS image optimisation and managing image quality.

RESULTS

Results demonstrated a significant improvement in knowledge, with an average increase in multiple choice question score of 61% (P < 0.0002), and that there was a 46% (P < 0.0001) average increase in the participants perceived understanding of TRUS scanner operation, and an increase of 36% (P < 0.001) in participants readiness to optimise image quality and mitigate image artefacts. Focus group data explored participants' experiences, perceptions and challenges with TRUS LDR PBT.

CONCLUSIONS

This study suggests a benefit in offering a simulation training workshop to medical physicists and the potential benefit to other healthcare professionals involved in prostate brachytherapy, by incorporating novel high-fidelity anthropomorphic PBT TRUS training simulators, in a simulated environment to practice ultrasound image optimisation for PBT image guidance. This approach to training would enable competency-based skill acquisition and continued proficiency or health professionals in the TRUS PBT procedure, outside of the surgical environment without direct exposure to patients.

New imaging modalities to consider for men with prostate cancer on active surveillance

PURPOSE

To discuss the potential utility of newer imaging modalities including micro-ultrasound and PSMA-PET for the detection of clinically significant prostate cancer, technologies that may gain roles as adjuncts to multiparametric magnetic resonance imaging (mpMRI) in the active surveillance (AS) setting.

METHODS

Narrative review of two new imaging modalities used for primary prostate cancer through April 2021. A targeted search was performed to identify current relevant literature on the role of new imaging modalities for primary prostate cancer using search terms "micro-ultrasound," "molecular imaging," "prostate cancer," "active surveillance," "multiparametric MRI," "PI-RADS," "PRI-MUS," and "detection rate." In addition, references of included articles were screened for further relevant publications.

RESULTS

Micro-ultrasound (micro-US) and prostate-specific membrane antigen-positron emission tomography (PSMA-PET) are increasing in their use and applicability to prostate cancer imaging. Micro-US is used for cancer detection and may identify higher grade cancers more accurately than conventional ultrasound, despite technical hurdles in its initial launch. PSMA-PET is highly sensitive and specific for high-grade and metastatic prostate cancer, though costly and not easily available. Though data are sparse, it may have an emerging role in cancer diagnosis in select localized cases, and in some men considering (or currently on) AS who have indications of more aggressive disease.

CONCLUSION

There are very limited data on micro-US and PSMA-PET in AS patients. However, given the ability of these modalities to identify high-grade cancer, their judicious use in AS patients may be of utility in the future.

Optimization of prostate biopsy - Micro-Ultrasound versus MRI (OPTIMUM): A 3-arm randomized controlled trial evaluating the role of 29 MHz micro-ultrasound in guiding prostate biopsy in men with clinical suspicion of prostate cancer

BACKGROUND

Micro-ultrasound (microUS) is a novel ultrasound-based imaging modality which has demonstrated the ability to visualize prostate cancer. Multiparametric MRI/ultrasound (mpMRI/US) fusion has recognized advantages for the performance of prostate biopsy, however, it encompasses additional cost, time and technical expertise to performing prostate biopsy in comparison to conventional trans-rectal ultrasound biopsy. MicroUS may simplify and optimize this pathway.

METHODS

OPTIMUM is a 3-arm randomized controlled trial comparing microUS guided biopsy with MRI/US fusion and MRI/MicroUS "contour-less" fusion. This trial will investigate whether microUS alone, or in combination with mpMRI, provides effective guidance during prostate biopsy for the detection of clinically significant prostate cancer (csPCa) for biopsy naïve subjects. 1200 subjects will be randomized. The economic impact will be evaluated.

RESULTS

The rate of csPCa (defined as Grade Group 2 and above) in each arm will be compared. The primary hypothesis is non-inferiority of csPCa rate between the MRI/US fusion arm and the microUS-only arm (including the blinded microUS-only portion of the MRI/MicroUS arm). As a secondary objective, the csPCa rate between MRI/MicroUS fusion and MRI/US fusion arms will also be compared. Other secondary objectives include the increase in rate of patients diagnosed with csPCa due to each type of sample (mpMRI targeted, microUS targeted, systematic), the negative predictive value of each imaging modality, and a health economic analysis of the procedures in each arm.

CONCLUSIONS

OPTIMUM will determine whether microUS can be used as an alternative to MRI/US fusion biopsy. The trial will also evaluate the efficacy of the simplified "contour-less" MRI/MicroUS fusion procedure. The adoption of the microUS technique will increase the proportion of men who can benefit from modern imaging-centric diagnostic strategies, and may help reduce variability, complexity, waiting time and cost within the diagnostic pathway.

Clinical values of transrectal ultrasound in judging GTV of cervical cancer

PURPOSE

To investigate the clinical value of transrectal ultrasound in judging the Gross Target Volume (GTV) of cervical cancer (CC).

METHODS

A total of 196 CC patients admitted to the Department of Radiotherapy, China-Japan Union Hospital, Jilin University, from January 2016 to June 2019 were selected as the study subjects. The GTVs before and after applicator insertion were determined by transrectal ultrasound and compared with those judged by MRI.

RESULTS

All 196 patients were successfully undergoing applicator insertion according to the pretreatment plan. The GTV doses reached the clinical requirements during treatment. There was no significant difference between the GTVs judged by MRI and ultrasound before insertion in terms of upper/lower diameter (MRI Before 1 vs. Ultrasound Before 1) (MB1 vs. UB1), left/right diameter (MB2 vs. UB2), or ventral/dorsal diameter (MB3 vs. UB3), and the intragroup correlation coefficients (ICC) were 0.59, 0.77, and 0.66, respectively; moreover, there was no significant difference between the GTVs judged by MRI and ultrasound after insertion in terms of MRI After one vs. Ultrasound After one (MA1 vs. UA1), MA2 vs. UA2, and MA3 vs. UA3, and the ICC values were 0.62, 0.79, and 0.76, respectively.

CONCLUSIONS

Transrectal ultrasound can satisfactorily determine the GTV of CC and has certain value in brachytherapy for CC.

Robotic Transrectal Computed Tomographic Ultrasound with Artificial Neural Network Analysis: First Validation and Comparison with MRI-Guided Biopsies and Radical Prostatectomy

INTRODUCTION

There is still a lack of availability of high-quality multiparametric magnetic resonance imaging (mpMRI) interpreted by experienced uro-radiologists to rule out clinically significant PC (csPC). Consequently, we developed a new imaging method based on computed tomographic ultrasound (US) supported by artificial neural network analysis (ANNA).

METHODS

Two hundred and two consecutive patients with visible mpMRI lesions were scanned and recorded by robotic CT-US during mpMRI-TRUS biopsy. Only significant index lesions (ISUP ≥2) verified by whole-mount pathology were retrospectively analyzed. Their visibility was reevaluated by 2 blinded investigators by grayscale US and ANNA.

RESULTS

In the cohort, csPC was detected in 105 cases (52%) by mpMRI-TRUS biopsy. Whole-mount histology was available in 44 cases (36%). In this subgroup, mean PSA level was 8.6 ng/mL, mean prostate volume was 33 cm3, and mean tumor volume was 0.5 cm3. Median PI-RADS and ISUP of index lesions were 4 and 3, respectively. Index lesions were visible in grayscale US and ANNA in 25 cases (57%) and 30 cases (68%), respectively. Combining CT-US-ANNA, we detected index lesions in 35 patients (80%).

CONCLUSIONS

The first results of multiparametric CT-US-ANNA imaging showed promising detection rates in patients with csPC. US imaging with ANNA has the potential to complement PC diagnosis.

The Comparison of Imaging and Clinical Methods to Estimate Prostate Volume: A Single-Centre Retrospective Study

BACKGROUND

Prostate volume (PV) is a useful tool in risk stratification, diagnosis, and follow-up of numerous prostatic diseases including prostate cancer and benign prostatic hypertrophy. There is currently no accepted ideal PV measurement method.

OBJECTIVE

This study compares multiple means of PV estimation, including digital rectal examination (DRE), transrectal ultrasound (TRUS), and magnetic resonance imaging (MRI), and radical prostatectomy specimens to determine the best volume measurement style.

METHODS

A retrospective, observational, single-site study with patients identified using an institutional database was performed. A total of 197 patients who underwent robot-assisted radical prostatectomy were considered. Data collected included age, serum PSA at the time of the prostate biopsy, clinical T stage, Gleason score, and PVs for each of the following methods: DRE, TRUS, MRI, and surgical specimen weight (SPW) and volume.

RESULTS

A paired t test was performed, which reported a statistically significant difference between PV measures (DRE, TRUS, MRI ellipsoid, MRI bullet, SP ellipsoid, and SP bullet) and the actual prostate weight. Lowest differences were reported for SP ellipsoid volume (M = -2.37; standard deviation [SD] = 10.227; t[167] = -3.011; and p = 0.003), MRI ellipsoid volume (M = -4.318; SD = 9.53; t[167] = -5.87; and p = 0.000), and MRI bullet volume (M = 5.31; SD = 10.77; t[167] = 6.387; and p = 0.000).

CONCLUSION

The PV obtained by MRI has proven to correlate with the PV obtained via auto-segmentation software as well as actual SPW, while also being more cost-effective and time-efficient. Therefore, demonstrating that MRI estimated the PV is an adequate method for use in clinical practice for therapeutic planning and patient follow-up.

Transrectal ultrasound guided prostate biopsy performed by supervised junior and senior residents is safe and does not result in inferior outcomes

PURPOSE

To compare transrectal ultrasound guided prostate biopsy (TRUSBx) cancer detection and complication rates between residents at different levels of training and attending physicians at a single academic center.

METHODS

We performed a retrospective review of consecutive series of 623 men undergoing TRUSBx from June 2014 to February 2017. The procedure was performed either by resident physicians under direct supervision by an attending physician or by an attending physician. In total, junior residents, senior residents and attending physicians performed 244, 212, and 167 biopsies, respectively. Prostate cancer detection, 30-day complications, and 30-day hospitalizations rates were the outcomes of interest. We performed multivariable logistic regression analysis to identify predictors of these outcomes and examined the hypothesis that TRUSBx performed by trainees would not be associated with inferior outcomes.

RESULTS

There was no statistically significant difference in patient populations between the three groups when stratified by age, BMI, Charleston co-morbidity index, aspirin use, PSA level and palpable nodule on DRE. Prostate cancer was detected in 43.8% of the biopsies and there was no difference in detection rates (P = 0.53), Gleason score (P = 0.11), number of positive cores (P = 0.95), 30-day hospitalization (P = 0.86), and 30-day complication rates (P = 0.67) between TRUSBx performed by trainees and attending physicians.

CONCLUSIONS

TRUSBx performed by residents and attending physicians yielded equivalent rates of cancer detection with no significant difference in 30-day complications or 30-day hospitalizations rates. There was no difference in outcomes between junior and senior residents suggesting that with adequate faculty supervision, it is safe for trainees at all levels to perform prostate biopsies.

Recent Advances and Current Role of Transperineal Prostate Biopsy

"Approximately 1 million prostate biopsies are performed each year in the United States. This procedure has traditionally been performed using a transrectal approach, which is associated with a significant risk of infectious complications including sepsis. In recent years, transperineal prostate biopsy has been increasingly adopted due to its lower associated infectious risk. In this review, we explore the benefits of the transperineal approach for performing prostate biopsy and detail technical advancements that have allowed for this procedure to now be routinely performed in the outpatient settings under local anesthesia."

MRI-targeted biopsy versus standard transrectal ultrasound-guided biopsy: a systematic review and meta-analysis of randomized controlled trials

PURPOSE

For men with a suspicion of prostate cancer (PCa), the transrectal ultrasound-guided biopsy (TRUS-Bx) was recommended. Multi-parametric magnetic resonance imaging (mp-MRI) could be more useful to more accurately selected patients who are with a clinical suspicion of PCa and eligible for biopsy, and avoid a biopsy if the result was negative. In the present study, we compared the MRI-targeted biopsy (MRI-TBx) with TRUS-Bx.

METHODS

We searched the following online database: PubMed, Embase, and Cochrane Library, and the search was updated to March 2019.

RESULTS

Finally, a total of 8 randomized controlled trials (RCTs) comprising 2593 patients were enrolled in the final analysis. MRI-TBx and TRUS-Bx did not significantly differ in overall PCa (RR = 1.30; 95% CI 0.98-1.72; P = 0.067), clinically significant PCa (RR = 1.35; 95% CI 0.98-1.86; P = 0.065), and clinically insignificant PCa (RR = 0.76; 95% CI 0.40-1.46; P = 0.416). While in patients with initial biopsy, MRI-TBx had a significantly higher detection rate of overall PCa (RR = 1.40; 95% CI 1.01-1.94; P = 0.045).

CONCLUSION

In the present study, we found that MRI-TBx potentially benefits the detection of overall and clinically significant PCa compared with TRUS-Bx in patients with a suspicion of PCa. Furthermore, in patients with initial biopsy, MRI-TBx had a significantly higher detection rate of overall PCa and a potentially higher detection rate of clinically significant PCa. While for patients with prior negative biopsy, we did not detect significant differences in overall and clinically significant PCa between two groups. More large and multicenter RCTs are further required.

Prostate cancer management: long-term beliefs, epidemic developments in the early twenty-first century and 3PM dimensional solutions

In the early twenty-first century, societies around the world are facing the paradoxal epidemic development of PCa as a non-communicable disease. PCa is the most frequently diagnosed cancer for men in several countries such as the USA. Permanently improving diagnostics and treatments in the PCa management causes an impressive divergence between, on one hand, permanently increasing numbers of diagnosed PCa cases and, on the other hand, stable or even slightly decreasing mortality rates. Still, aspects listed below are waiting for innovate solutions in the context of predictive approaches, targeted prevention and personalisation of medical care (PPPM / 3PM).A.PCa belongs to the cancer types with the highest incidence worldwide. Corresponding economic burden is enormous. Moreover, the costs of treating PCa are currently increasing more quickly than those of any other cancer. Implementing individualised patient profiles and adapted treatment algorithms would make currently too heterogeneous landscape of PCa treatment costs more transparent providing clear "road map" for the cost saving.B.PCa is a systemic multi-factorial disease. Consequently, predictive diagnostics by liquid biopsy analysis is instrumental for the disease prediction, targeted prevention and curative treatments at early stages.C.The incidence of metastasising PCa is rapidly increasing particularly in younger populations. Exemplified by trends observed in the USA, prognosis is that the annual burden will increase by over 40% in 2025. To this end, one of the evident deficits is the reactive character of medical services currently provided to populations. Innovative screening programmes might be useful to identify persons in suboptimal health conditions before the clinical onset of metastasising PCa. Strong predisposition to systemic hypoxic conditions and ischemic lesions (e.g. characteristic for individuals with Flammer syndrome phenotype) and low-grade inflammation might be indicative for specific phenotyping and genotyping in metastasising PCa screening and disease management. Predictive liquid biopsy tests for CTC enumeration and their molecular characterisation are considered to be useful for secondary prevention of metastatic disease in PCa patients.D.Particular rapidly increasing PCa incidence rates are characteristic for adolescents and young adults aged 15-40 years. Patients with early onset prostate cancer pose unique challenges; multi-factorial risks for these trends are proposed. Consequently, multi-level diagnostics including phenotyping and multi-omics are considered to be the most appropriate tool for the risk assessment, prediction and prognosis. Accumulating evidence suggests that early onset prostate cancer is a distinct phenotype from both aetiological and clinical perspectives deserving particular attention from view point of 3P medical approaches.

How Often Does Magnetic Resonance Imaging Detect Prostate Cancer Missed by Transrectal Ultrasound?

BACKGROUND

Lesion-targeted prostate biopsy based on multiparametric magnetic resonance imaging (mpMRI) has been shown to be superior to systematic transrectal ultrasound (TRUS) biopsy (SBx) alone in men at risk for prostate cancer (PCa). However, the incremental benefit of MRI-targeted biopsy (MBx) beyond SBx with ultrasound-targeted biopsy (UBx) is less clear.

OBJECTIVE

We performed a three-way comparison of UBx versus MBx versus SBx for PCa detection.

DESIGN, SETTING, AND PARTICIPANTS

A prospective, single-center cohort study was conducted on consecutive patients with PCa suspicion or low-risk PCa on active surveillance (AS). All men had at least one lesion (Prostate Imaging Reporting and Data System [PI-RADS] ≥3) on pre-biopsy mpMRI. UBx, MBx, and SBx were performed during the same encounter, and the urologists were blinded to MRI results and targeting until both SBx and UBx were completed.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

The ability of each biopsy type to identify the highest grade group (GG) was determined, and UBx and MBx were compared using a paired t test.

RESULTS AND LIMITATIONS

We prospectively enrolled 201 consecutive men undergoing targeted prostate biopsy: 72 (36%) were biopsy-naïve, 34 (17%) had a prior negative SBx, and 95 (47%) were on AS. Median age and prostate-specific antigen were 66 yr (interquartile range [IQR] 62-71) and 6.8 ng/ml (IQR 4.9-9.8), respectively. Suspicious hypoechoic lesions were reported on TRUS in 69%. Among the 169 men with PCa, SBx detected the highest GG or was equivalent to UBx/MBx in 136 (80%) men. UBx detected the highest GG or was equivalent to MBx in 19 (11%) men, and MBx alone detected the highest GG in 14 (8%) men. There was no significant difference between UBx and MBx in direct comparison (p = 0.08). Limitations include that patients were not randomized, our population was heterogeneous, and TRUS expertise at a tertiary care academic center might not reflect routine practice.

CONCLUSIONS

In the setting of high expertise and experience with both ultrasound and MRI, MBx offers only a modest benefit over SBx and UBx.

PATIENT SUMMARY

At a highly experienced academic medical center, we examined the detection rates of prostate cancer among men undergoing prostate biopsy using three techniques: transrectal ultrasound lesion-targeted biopsy, magnetic resonance imaging-targeted biopsy, and systematic biopsy. We identified a few more cases of aggressive prostate cancer with magnetic resonance imaging-targeted biopsy, but a large majority was found by ultrasound alone.

A deep learning method for real-time intraoperative US image segmentation in prostate brachytherapy

PURPOSE

This paper addresses the detection of the clinical target volume (CTV) in transrectal ultrasound (TRUS) image-guided intraoperative for permanent prostate brachytherapy. Developing a robust and automatic method to detect the CTV on intraoperative TRUS images is clinically important to have faster and reproducible interventions that can benefit both the clinical workflow and patient health.

METHODS

We present a multi-task deep learning method for an automatic prostate CTV boundary detection in intraoperative TRUS images by leveraging both the low-level and high-level (prior shape) information. Our method includes a channel-wise feature calibration strategy for low-level feature extraction and learning-based prior knowledge modeling for prostate CTV shape reconstruction. It employs CTV shape reconstruction from automatically sampled boundary surface coordinates (pseudo-landmarks) to detect the low-contrast and noisy regions across the prostate boundary, while being less biased from shadowing, inherent speckles, and artifact signals from the needle and implanted radioactive seeds.

RESULTS

The proposed method was evaluated on a clinical database of 145 patients who underwent permanent prostate brachytherapy under TRUS guidance. Our method achieved a mean accuracy of [Formula: see text] and a mean surface distance error of [Formula: see text]. Extensive ablation and comparison studies show that our method outperformed previous deep learning-based methods by more than 7% for the Dice similarity coefficient and 6.9 mm reduced 3D Hausdorff distance error.

CONCLUSION

Our study demonstrates the potential of shape model-based deep learning methods for an efficient and accurate CTV segmentation in an ultrasound-guided intervention. Moreover, learning both low-level features and prior shape knowledge with channel-wise feature calibration can significantly improve the performance of deep learning methods in medical image segmentation.

Contrast-enhanced transrectal ultrasound can reduce collection of unnecessary biopsies when diagnosing prostate cancer and is predictive of biochemical recurrence following a radical prostatectomy in patients with localized prostate cancer

Background

To investigate the value of using contrast-enhanced transrectal ultrasound (CETRUS) to reduce unnecessary collection of biopsies during prostate cancer diagnosis and its utility in predicting biochemical recurrence in patients with localized prostate cancer.

Methods

This was a prospective study of suspected prostate cancer patients who were evaluated with CETRUS followed by a prostate biopsy. Prostate blood flow via CETRUS was graded using a 5-point scale. The relationship between CETRUS score and biopsy outcome was then analyzed for all patients; univariate and multi-variate analyses were used to determine the probable prognostic factors for biochemical recurrence in patients with localized prostate cancer that underwent a radical prostatectomy.

Results

A total of 347 patients were enrolled in the study. Prostate cancer was found in 164 patients. A significant positive correlation (r = 0.69, p < 0.001) was found between CETRUS scores and prostate cancer incidence. Using CETRUS scores ≥2 as the threshold for when to biopsy could have safely reduced the number of biopsies taken overall by 12.1% (42/347) and spared 23.0% (42/183) of patients from undergoing an unnecessary biopsy. 77 patients with localized prostate cancer underwent a radical prostatectomy. The median follow-up time was 30 months (range: 8–56 months) and 17 of these 77 patients exhibited biochemical recurrence during the follow-up period. 3-year biochemical recurrence-free survival rates were 86% for patients with low CETRUS scores (≤ 3) and 59% for patients with high scores (> 3; p = 0.015). Multivariate Cox regression analysis indicated that CETRUS score was an independent predictor of biochemical recurrence (HR: 7.02; 95% CI: 2.00–24.69; p = 0.002).

Conclusions

CETRUS scores may be a useful tool for reducing the collection unnecessary biopsy samples during prostate cancer diagnosis and are predictive of biochemical recurrence in patients with localized prostate cancer following a radical prostatectomy.

Hybrid TRUS/CT with optical tracking for target delineation in image-guided adaptive brachytherapy for cervical cancer

Objective

To prospectively compare the interobserver variability of combined transrectal ultrasound (TRUS)/computed tomography (CT)- vs. CT only- vs. magnetic resonance imaging (MRI) only-based contouring of the high-risk clinical target volume (CTV_HR) in image-guided adaptive brachytherapy (IGABT) for locally advanced cervical cancer (LACC).

Methods

Five patients with LACC (FIGO stages IIb–IVa) treated with radiochemotherapy and IGABT were included. CT, TRUS, and T2-weighted MRI images were performed after brachytherapy applicator insertion. 3D-TRUS image acquisition was performed with a customized ultrasound stepper device and software. Automatic applicator reconstruction using optical tracking was performed in the TRUS dataset and TRUS and CT images were fused with rigid image registration with the applicator as reference structure. The CTV_HR (based on the GEC-ESTRO recommendations) was contoured by five investigators on the three modalities (CTV_HR_CT, CTV_HR_TRUS-CT, and CTV_HR_MRI). A consensus reference CTV_HR_MRI (MRIref) was defined for each patient. Descriptive statistics and overlap measures were calculated using RTslicer (SlicerRT Community and Percutaneous Surgery Laboratory, Queen’s University, Canada), comparing contours of every observer with one another and with the MRIref.

Results

The interobserver coefficient of variation was 0.18 ± 0.05 for CT, 0.10 ± 0.04 for TRUS-CT, and 0.07 ± 0.03 for MRI. Interobserver concordance in relation to the MRIref expressed by the generalized conformity index was 0.75 ± 0.04 for MRI, 0.51 ± 0.10 for TRUS-CT, and 0.48 ± 0.06 for CT. The mean CTV_HR_CT volume of all observers was 71% larger than the MRIref volume, whereas the mean CTV_HR_TRUS-CT volume was 15% larger.

Conclusion

Hybrid TRUS-CT as an imaging modality for contouring the CTV_HR in IGABT for LACC is feasible and reproducible among multiple observers. TRUS-CT substantially reduces overestimation of the CTV_HR volume of CT alone while maintaining similar interobserver variability.

Targeted Biopsy With Reduced Number of Cores: Optimal Sampling Scheme in Patients Undergoing Magnetic Resonance Imaging/Transrectal Ultrasound Fusion Prostate Biopsy

The 3 Tesla (3T) magnetic resonance imaging (MRI) combined ultrasound (TRUS) targeted biopsy plus 12-core systematic biopsy (TBx + 12-SBx) was considered a reliable method for prostate cancer (PCa) diagnosis. To find another optimal sampling scheme with fewer cores and the same efficiency as TBx + 12-SBx for prostate biopsy, 113 patients who underwent five different hypothetical sampling schemes were analyzed and compared with TBx + 12-SBx. The detection rates of targeted biopsy plus 6-core lateral systematic biopsy (TBx + lateral 6-SBx) for PCa and clinically significant prostate cancer (csPCa) (99.1% and 96.4%, respectively) were higher than other schemes, and the area under the receiver operating characteristic curve of TBx + lateral 6-SBx for PCa and csPCa (0.991 and 0.990, respectively) were also significantly higher than other sampling schemes except TBx plus 6-core ipsilateral systematic biopsy (TBx + ipsilateral 6-SBx). Additionally, TBx + lateral 6-SBx had the lowest missed diagnosis rate. Thus, the TBx + lateral 6-SBx may be the optimal scheme for patients undergoing MRI/TRUS fusion prostate biopsy.

Prospective Evaluation of 68Ga-labeled Prostate-specific Membrane Antigen Ligand Positron Emission Tomography/Computed Tomography in Primary Prostate Cancer Diagnosis

BACKGROUND

Positron emission tomography (PET)/computed tomography (CT) with ⁶⁸Ga-labeled prostate-specific membrane antigen ligand (⁶⁸Ga-PSMA) may represent the most promising alternative to multiparametric magnetic resonance imaging (mpMRI) for prostate cancer (PCa) diagnosis.

OBJECTIVE

To test the diagnostic performance of ⁶⁸Ga-PSMA PET/CT in this clinical context.

DESIGN, SETTING, AND PARTICIPANTS

From January 2017 to December 2018 we prospectively enrolled 97 patients with persistently elevated prostate-specific antigen and/or Prostate Health Index score, negative digital rectal examination, and previous negative biopsy. We also included patients with either negative mpMRI or contraindications to or positive mpMRI but previous negative biopsy.

INTERVENTION

Patients underwent 68Ga-PSMA PET/CT with additional pelvic reconstruction.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

The primary endpoint of the study was the diagnostic performance of ⁶⁸Ga-PSMA PET/CT in detecting malignant lesions and clinically significant PCa (Gleason score [GS] ≥7).

RESULTS AND LIMITATIONS

⁶⁸Ga-PSMA PET/transrectal ultrasound fusion biopsy was performed in 64 of 97 patients (66%) for 114 regions of interest (ROIs). Forty patients (41%) had already undergone mpMRI with either a negative result for PCa (n = 15; 22 ROIs) or a positive mpMRI result but a previous negative biopsy. According to pathology, 23 patients (36%) had evidence of PCa: eight (16 ROIs) with GS 6, 13 (21 ROIs) with GS 7 (3 + 4 or 4 + 3), one (2 ROIs) with GS 8, and one (2 ROIs) with GS 10. Clinically significant PCa was identified in four patients with previous negative mpMRI (25%). PET/CT demonstrated PCa in seven patients (14 ROIs) with previous positive mpMRI and negative biopsy. The median maximum standardized uptake value (SUVmax) and median SUV ratio were significantly higher for PCa lesions than for benign lesions (p <  0.001). Optimal cutoff points obtained for SUVmax (>5.4) and SUV ratio (>2.2) could identify clinically significant PCa with accuracy of 81% and 90%, respectively.

CONCLUSIONS

In our cohort of patients with high suspicion of cancer,⁶⁸Ga-PSMA PET/CT was capable of detecting malignancy and accurately identifying clinically relevant PCa.

PATIENT SUMMARY

Positron emission tomography/computed tomography with a ⁶⁸Ga-labeled ligand for prostate-specific membrane antigen is capable of detecting prostate cancer in patients with a high suspicion of cancer and a previous negative biopsy.

Comparison of CTVHR and organs at risk contours between TRUS and MR images in IB cervical cancers: a proof of concept study

Purpose

To compare CTV_HR and OAR dimensions and inter-rater agreement between magnetic resonance (MR) and trans-rectal ultrasound (TRUS) images in IB cervical cancer patients.

Methods

IB cervical cancer patients treated with (chemo)radiotherapy plus MR-guided brachytherapy (BT) were prospectively enrolled in this study. Radiation oncologists contoured CTV_HR and OARs in pre-BT MR images (MRI) and intra-operative TRUS images. These contours were subsequently compared in regard to volume and dimension. Contour inter-rater agreement analysis was also investigated using kappa index (KI). Stata 15.0 was used for statistical analysis and a p-value < 0.05 was considered statistically significant.

Results

TRUS CTV_HR volumes were statistically smaller than the respective MRI contoured volumes. TRUS CTV_HR thickness was found to be consistently smaller than MRI contours in all patients. No statistical difference was seen in width and height between the two different imaging modalities. MRI contours had a median KI of 0.66 (range: 0.56–0.77) while TRUS-based contours had a median KI of 0.64 (range: 0.47–0.77). Bladder and rectum had very satisfactory KI in both imaging modalities. Vaginal contours had moderate agreement in MR (0.52) and in TRUS images (0.58).

Conclusion

TRUS images allow good visualization of CTV_HR and OARs in IB cervical cancer patients. Inter-rater contour variability was comparable between TRUS and MR images. TRUS is a promising modality on its own for image-guided BT.

Evaluation of ovarian volume by transrectal ultrasonography in cattle; affect of the day of the estrous cycle and validation of a method of subtracting of corpora lutea and follicle volume

This research was conducted to evaluate a method for determining ovarian volume using ultrasonography; specifically, how the day of the estrous cycle affected ovarian volume, and the application of a formula for adjusted ovarian volume (ADJ VOL) and its relationship to actual ovarian volume. Cows (n = 22) were estrous synchronized and subjected to serial transrectal ultrasonographic evaluations, performed every 48 h from the day prior to ovulation until day 9 of the subsequent estrous cycle. Measurements obtained from recorded ultrasonographic images were used to determine actual ovarian volume cm³ = [0.523 X (D1 X D2 X D3)] and adjusted ovarian volume (ADJ VOL) cm³ = [0.523 X (D1 X D2 X D3)]- 43 (πrCL²) - 43 (πrF²) on days 1, 3, 5, 7, 9 of the estrous cycle. A third objective was to evaluate the concordance correlation coefficient (ρc) between post-mortem ovarian measurements and the water displacement test. Ovarian volume increased with each day of the estrous cycle from Day 1 to Day 7. Day of the estrous cycle affected ovarian volume (P <  0.001). When applying the formula for ADJ VOL, there was not an effect of day of the estrous cycle (P  = 0.509). Ovarian volume, results ex-vivo, were very consistent with the displacement volume results (ρ_c = 0.942). If large ovarian structures are present, and the day of the estrous cycle is unknown, then the formula for ADJ VOL can be used to estimate ovarian volume on Day 1 of the estrous cycle.

[Acute postoperative sepsis mimicking symptomology suspicious for malignant hyperthermia: case report]

BACKGROUND

Sepsis is a life-threatening organ dysfunction with non-specific clinical features that can mimic other clinical conditions with hyper metabolic state such as malignant hyperthermia. Perioperatively anesthesia providers come across such scenarios, which are extremely challenging with the need for urgent intervention.

OBJECTIVE

To illustrate the need for early intervention and consultation for added assistance to approach and rule out malignant hyperthermia and other possible causes during such a scenario.

CASE REPORT

A 63-year-old male underwent an uneventful elective flexible cystoscopy and transrectal ultrasound-guided prostate biopsy. Postoperatively he developed symptoms raising suspicion for malignant hyperthermia. Immediately malignant hyperthermia protocol was initiated that included administration of dantrolene and consultation of malignant hyperthermia association hotline along with other diagnostic and interventional management aimed at patient optimization. While early administration of dantrolene helped in hemodynamically stabilizing the patient, the consultation with other providers and malignant hyperthermia association hotline along with repeated examinations and lab works helped in ruling out malignant hyperthermia as the possible diagnosis. The patient later recovered in the intensive care unit where he was treated for the bacteremia that grew in his blood cultures.

CONCLUSIONS

Sepsis shares clinical symptoms that mimic malignant hyperthermia. While sepsis rapidly progresses to secondary injuries, malignant hyperthermia is life threatening. Providing ideal care requires good clinical judgment and a high level of suspicion where timely and appropriate care such as early administration of dantrolene and consultation of malignant hyperthermia association hotline for added assistance can influence positive outcomes.

Necessity of differentiating small (< 10 mm) and large (≥ 10 mm) PI-RADS 4

PURPOSE

Prostate Imaging Reporting and Data System version 2 (PI-RADSv2) provides reasonable performance in detecting significant cancers. Still, it is unclear about whether all PI-RADS 4 lesions show the same cancer detection rate (CDR) regardless of tumor size. The aim was to compare the CDRs of small (< 10 mm) and large (≥ 10 mm) PI-RADS 4.

METHODS

After magnetic resonance imaging (MRI) was performed in 684 men, a radiologist interpreted the MR images and detected 281 index lesions categorized as PI-RADS 4 in 281 men. PI-RADS 4 lesions were divided into small and large groups on size of 10 mm. Overall and significant CDRs were compared between the groups. A significant cancer was defined as one with Gleason score (GS) ≥ 7 or tumor volume ≥ 0.5 ml. Tumor volumes were roughly calculated as πr³4/3 (π = 3.14 and r = a half of tumor size) and were compared between the groups. Standard reference was a biopsy examination. Fisher's exact and Mann-Whitney tests were used for statistical analysis.

RESULTS

The overall CDRs of small and large groups were 39.0% (53/136) and 59.3% (86/145), respectively, (p = 0.0008). The median tumor volumes of cancer-proven small and large groups were 0.18 ml (0.01-0.38 ml) and 0.70 ml (0.52-1.44 ml), respectively (p < 0.0001). Using GS or tumor volume, the significant CDRs of these groups were 26.5% (36/136) and 59.3% (86/145), respectively (p < 0.0001), and using GS alone, 26.5% (36/136) and 39.3% (57/145), respectively (p = 0.0232).

CONCLUSIONS

PI-RADS 4 lesions should be sub-divided on size of 10 mm because of different significant CDRs.

The Role of Transrectal Ultrasound for Finding Focal Lesions in Prostate Cancer Detection Compared to Systematic Sextant Biopsy

OBJECTIVES

To evaluate the difference in cancer detection rate between targeted biopsy of focal lesions detected on transrectal ultrasound (TRUS) and systematic sextant biopsy.

MATERIALS AND METHODS

This retrospective study included patients who underwent TRUS-guided prostate biopsy between April 2014 and April 2017 and classified them into three groups: (1) sextant biopsy group patients underwent systematic sextant biopsy without evaluation of focal lesions on TRUS (n = 400), (2) focal lesion group patients underwent targeted biopsy for TRUS-detected lesions (n = 496), and (3) nonfocal lesion group patients had no TRUS-detected focal lesions (n = 222). Positive biopsy rates were compared using Chi-square tests between biopsy groups in all patients and two subgroups divided by prostate-specific antigen (PSA) level of 10 ng/mL.

RESULTS

The positive biopsy rate decreased in the order of the focal lesion group, the sextant biopsy group, and the nonfocal lesion group. All prostate cancers and prostate cancers with a Gleason score ≥7 were detected more frequently among patients with PSA ≤10 ng/mL in the focal lesion group than in the sextant biopsy group ( p = 0.008 and 0.007, respectively) and less frequently among patients with PSA >10 ng/mL in the nonfocal lesion group than in the sextant biopsy group ( p = 0.007 and 0.003, respectively).

CONCLUSION

In conclusion, searching focal lesion by TRUS is useful for improving the positive biopsy rate and risk stratification of PCa compared to systematic sextant biopsy without careful TRUS examination.

Cancer Location in Upgrading and Detection after Transperineal Template-Guided Mapping Biopsy for Patients in Active Surveillance and Negative Transrectal Ultrasonography-Guided Prostate Biopsy

OBJECTIVES

We investigated the efficacy of transperineal template-guided mapping biopsy (TTMB) for patients on active surveillance (AS) or those with previous negative transrectal ultrasound-guided biopsy (TRUS-Bx).

METHODS

We retrospectively analyzed 99 patients on AS and 60 patients with previous negative TRUS-Bx, which is a total of 159 patients who underwent TTMB from May 2017 to January 2019. Cancer location was analyzed with focus on the anterior and apex lesions of the prostate after TTMB. Multiparametric magnetic resonance imaging was performed before TTMB. Cancer location after TTMB in 138 patients, excluding 21 patients who were not eligible for analysis (4 patients on AS and 17 patients with previous negative TRUS-Bx) was compared with Prostate Imaging-Reporting and Data System version 2 (PI-RADSTM v2) score. Factors that may affect detecting cancer after TTMB with previous negative TRUS-Bx was analyzed using a logistic regression model.

RESULTS

In AS patients, 29 patients (29.3%) exhibited an upgrade in Gleason score (GS) after TTMB. Among them, 22 patients (75.9%) showed at the anterior or apex lesions. In patients with previous negative TRUS-Bx, 18 patients (30.0%) were diagnosed with prostate cancer. Among them, 13 patients (72.2%) exhibited cancer at the anterior or apex lesion. Among the 25 AS patients with PI-RADSTM score 1-2, 5 patients (20.0%) showed an upgrade in GS. Among the 26 patients with previous negative TRUS-Bx and PI-RADSTM score 1-2, 6 patients (23.1%) had cancer. In multivariate regression model, prostate volume (OR 0.951) was identified as the predictor for a positive biopsy result after TTMB with previous negative TRUS-Bx.

CONCLUSIONS

TTMB is efficient for patients on AS in the detection of upgraded cancer located in anterior or apex or those with previous negative TRUS-Bx in the detection of anterior or apex cancer. In PI-RADSTM score 1-2, a substantial proportion of patients after experienced upgrade in GS on AS patients or cancer detection on previous negative TRUS-Bx. Moreover, we identified prostate volume is the independent predictor for a positive biopsy result after TTMB with previous negative TRUS-Bx.

Etiology, Diagnosis, and Management of Seminal Vesicle Stones

Background/Aims

Seminal vesicle (SV) stones are a rare, and thus readily misdiagnosed condition in practice. Understanding the etiology, diagnosis, and management are crucial to guide a urologist's care, and are provided in this literature review.

Methods

The inclusion criteria for the literature search, using the search engines MEDLINE® and PubMed was conducted using a combined query of "seminal vesicle stone" and the following keywords: calculi, hematospermia, calcification, and transrectal ultrasound (TRUS).

Results

The etiology of SV stones is currently unknown where majority of the patients present with having painful ejaculation and hematospermia. However, clinicians have reported potential etiologies by categorization as an inflammatory or non-in-flammatory. A majority of the previous cases had shown multiple stones being present in the SV duct system that are typically diagnosed through radiological examination such as TRUS, MRI, or plain radiographs. Amongst the many imaging approaches, TRUS remains the primary imaging diagnoses of SV calculi. Transurethral seminal vesiculoscopy has shown to be used in an abundant of the case reports to be an ideal surgical approach for managing small SV stones. In regard to larger stones, a transperitoneal laparoscopic protocol is proper.

Conclusion

The current imaging techniques have increased the case reports and diagnosis of SV calculi; however, more research is warranted for understanding the pathogenesis of the formation of SV stones. An optimal management of the extraction of SV stones depends on a number of factors such as size and location.

Computerized Tomography Criteria as a Tool for Simplifying the Assessment of Locally Advanced Rectal Cancer

BACKGROUND

Rectal cancer represents a leading cause of mortality worldwide. Staging defines the local and distant extent of the disease, guides management, and predicts prognosis. Different modalities are available for staging including TRUS (transrectal ultrasound), CT (computed tomography), and MRI (magnetic resonance imaging).

OBJECTIVE

The objective of this study was to screen and isolate CT imaging parameters suggestive of advanced rectal cancer and its utility as a tool in simplifying the staging protocol making further imaging studies unnecessary.

DESIGN

Retrospective, single center study.

PATIENTS AND SETTINGS

Seventy-five patients with rectal carcinoma were included and were divided into two groups according to their T score and nodal involvement status, as diagnosed by TRUS. Group 1 (n = 15) "local disease" (T1/T2 N0) and group 2 (n = 60) "locally advanced disease" are both eligible for neoadjuvant treatment (N/any T or T3/any N). For each patient, three CT imaging parameters that represent locally advanced disease, i.e., perirectal fat infiltration, local lymphadenopathy, and rectal wall thickening, were evaluated and compared between the two groups.

MAIN OUTCOME MEASURE

The capability of CT imaging to accurately predict locally advanced rectal carcinoma.

RESULTS

Rectal wall thickening on CT was found to have 92% PPV and perirectal lymphadenopathy 96% PPV for predicting a locally advanced stage. A combination of those two parameters results in a predictive PPV of 98%.

LIMITATIONS

This was a single center retrospective study, with a relatively small cohort.

CONCLUSIONS

CT is a valuable tool in the assessment and management of rectal carcinoma as it can identify locally advanced rectal cancer. This enables treatment without any further unnecessary evaluation.

[Fusion biopsies for primary diagnosis of prostate cancer : Implementation, benefits, and clinical aspects]

Prostate carcinoma is one of the most common tumors worldwide. Histological confirmation by biopsy is an obligatory part of the diagnostic approach. The main problem of the 10-12-fold transrectal ultrasound-guided (TRUS) biopsy, which has so far been regarded as the gold standard, is the underdiagnosis of clinically significant cancer. MRI-based procedures, so-called fusion biopsies, have shown superior results when compared to conventional biopsies. There are three different approaches (cognitive and software-based MRI/TRUS fusion and in-bore biopsy) with comparable detection rates but differences in the technical aspects and time involvement. In order to reduce fusion errors, targeted biopsies should consist of multiple cores. There is currently no clear preference for the access pathway (transrectal or transperineal), but clinical parameters such as infection risk or location of the tumor can influence the decision. While the German S3 guideline considers MRI prior to primary biopsy to be optional, the 2019 European Association of Urology guidelines already recommend MRI prior to biopsy for all patients. The combination of MRI-targeted and systematic biopsy offers the highest detection rates with the disadvantage that more low-risk tumors are diagnosed. Both the patient and the urologist benefit from an improved informative value of the biopsy when deciding on active surveillance as well as when planning invasive therapies.

Free-hand transperineal prostate biopsy provides acceptable cancer detection and minimizes risk of infection: evolving experience with a 10-sector template

INTRODUCTION AND OBJECTIVES

Free-hand transperineal prostate (fTP-Bx) biopsy offers an alternative to transrectal prostate biopsy (TRUS-Bx) in the diagnosis of prostate cancer. Our objectives were to determine whether fTP-Bx achieves cancer detection rates comparable to historic TRUS-Bx cohorts; to determine infectious and other complications associated with fTP-B; and to propose a standardized fTP-Bx template.

PATIENTS AND METHODS

We present a single institution, retrospective review of fTP-Bx in 1,000 men with elevated prostate-specific antigen, abnormal digital rectal examination, or on an active surveillance protocol. A fan-like biopsy scheme was used in 883 patients. A 10-sector prostate biopsy template was developed for use in the final 117 patients. The primary outcome was detection of any cancer and detection of clinically significant cancer (Grade Group ≥ 2). Secondary outcomes included procedural specifics and complications. Chi Square and Mann-Whitney U were used for analysis of categorical and continuous variables, respectively.

RESULTS

The median age of the cohort was 68 (interquartile range 61-74) years, and the median prostate-specific antigen was 7.9 (interquartile range 5.5-11.9) ng/ml. Total cancer (60.7%) and clinically significant cancer (40.3%) detection for fTP-Bx were comparable to those reported for TRUS-Bx. Detection of any cancer (70.9% vs. 59.3%, P < 0.01) and clinically significant cancer (51.3% vs. 38.9%, P = 0.01) was higher using the 10-sector biopsy template relative to the fan-like pattern. No patients were hospitalized for sepsis and no culture-proven urinary tract infections were diagnosed.

CONCLUSION

Cancer detection rates using fTP-Bx are comparable to TRUS-Bx, and fTP-Bx nearly eliminates the risk of infection. We propose a 10-sector biopsy template for fTP-Bx that easily translates to established MRI prostate sector maps for use in clinical care and future research studies exploring the efficacy of MRI-guided fTP-Bx.

A deep learning approach for real time prostate segmentation in freehand ultrasound guided biopsy

Targeted prostate biopsy, incorporating multi-parametric magnetic resonance imaging (mp-MRI) and its registration with ultrasound, is currently the state-of-the-art in prostate cancer diagnosis. The registration process in most targeted biopsy systems today relies heavily on accurate segmentation of ultrasound images. Automatic or semi-automatic segmentation is typically performed offline prior to the start of the biopsy procedure. In this paper, we present a deep neural network based real-time prostate segmentation technique during the biopsy procedure, hence paving the way for dynamic registration of mp-MRI and ultrasound data. In addition to using convolutional networks for extracting spatial features, the proposed approach employs recurrent networks to exploit the temporal information among a series of ultrasound images. One of the key contributions in the architecture is to use residual convolution in the recurrent networks to improve optimization. We also exploit recurrent connections within and across different layers of the deep networks to maximize the utilization of the temporal information. Furthermore, we perform dense and sparse sampling of the input ultrasound sequence to make the network robust to ultrasound artifacts. Our architecture is trained on 2,238 labeled transrectal ultrasound images, with an additional 637 and 1,017 unseen images used for validation and testing, respectively. We obtain a mean Dice similarity coefficient of 93%, a mean surface distance error of 1.10 mm and a mean Hausdorff distance error of 3.0 mm. A comparison of the reported results with those of a state-of-the-art technique indicates statistically significant improvement achieved by the proposed approach.

Could a bovine pregnancy rapid test be an alternative to a commercial pregnancy-associated glycoprotein ELISA test in dairy cattle?

The aim of the present study was to compare a Bovine Pregnancy Rapid Test (Ubio quickVET; BPRT) with a commercial ELISA-PAG test (Bovine Pregnancy Test DG29®) for early pregnancy diagnosis based on the presence of the PAG (pregnancy-associated glycoprotein) in dairy cattle between 30 and 40 days after artificial insemination (AI). Blood samples were collected from 212 cows between 30 and 40 days after artificial insemination (AI) to quantify the concentrations of PAG in each sample. Transrectal ultrasonography (TRUS) diagnosis of pregnancy was conducted at day 45 ± 3 after AI as the reference standard for the two PAG tests. The results indicated the sensitivity (Se) of the BPRT and DG29 for diagnosing pregnant cattle were 89.4% and 100%, respectively while the specificity (Sp) of the two tests for diagnosis of non-pregnant animals was 89.8% and 81.3%, respectively. Based on these results, the BPRT has a slightly lesser sensitivity and greater specificity than the DG29 test. Moreover, the accuracy of both tests was 94% and 90% respectively for DG29 and BPRT. This implies that the BPRT test could be considered an accurate test when compared to PAG-ELISA test and TRUS at days 30-40 after AI. The BPRT test, therefore, can be used as an alternative to the PAG-ELISA test with some constraints that need to be considered with its use.

Endoscopic Band Ligation to Treat a Massive Hemorrhoidal Hemorrhage Following a Transrectal Ultrasound-Guided Prostate Biopsy

Prostate cancer is commonly diagnosed by using a transrectal ultrasound (TRUS)-guided biopsy. Although this procedure is usually well tolerated, rarely it may be complicated by massive rectal bleeding. We report a case of a 77-year-old male who underwent a TRUS biopsy and subsequently developed recurrent episodes of rectal bleeding with syncope and anemia requiring the transfusion of multiple units of blood. A sigmoidoscopy revealed the source of the bleeding: a large hemorrhoid on the anterior wall of the rectum with an overlying ulceration. We successfully applied a band to ligate the hemorrhoid, and the patient's condition improved. To our knowledge, this case represents the first report of a successful band ligation to treat massive bleeding from a hemorrhoid that had been punctured in the course of the TRUS biopsy procedure.

Internal Fusion: exact correlation of transrectal ultrasound images of the prostate by detailed landmarks over time for targeted biopsies or follow-up

PURPOSE

Innovative imaging modalities are applied for diagnosing and follow-up of prostate cancer (PCa). To perform authentic targeted biopsies and evaluate prostate changes, it is essential to reliably identify and hit targets in their true anatomical location over time. A newly described image correlation method (Internal Fusion) allows precise correlation of serial transrectal ultrasound (TRUS) images in vitro and vivo. Identifiable morphologic structures such as prostatic calcifications define internal anchor points (Internal Landmarks) to facilitate exact correlation.

METHODS

After verification of Internal Fusion in vitro, 83 patients were included from January to August 2017 with at least one prior series of 5-mm spaced TRUS images stored as computed tomographic (US-CT) online data set. Two experienced operators collected new images in correlation with each cross-section of the previous examinations based on Internal Landmarks.

RESULTS

Of the 83 patients, fifty (60%) had prior negative biopsies. Fourteen (17%) wished US-CT targeted biopsies and PCa were detected in 7/14 patients (50%). Overall, accurate imaging correlations were attained in 369/397 slices (93%). In initial and repeat biopsy, 31/31 and 35/35 images could be correlated detecting PCa in 5/8 (63%) and 2/6 patients (33%). The longest observation of prostate changes over time (Trend Monitoring) with accurate image correlation was 8 years and 6 months.

CONCLUSIONS

Internal Fusion by Internal Landmarks ensures exact correlation in long-term follow-up. It is possible to precisely monitor trends in prostate tissue changes. In case of PCa suspicion, biopsies could be targeted with high accuracy by Internal Fusion, even over time.

A 12-year follow-up of ANNA/C-TRUS image-targeted biopsies in patients suspicious for prostate cancer

PURPOSE

PSA screening has been rehabilitated. PSA is not specific and can be elevated by benign reasons. Additionally, a subgroup of patients with prostate hyperplasia may harbor prostate cancer (PCa). During monitoring, the clinician aims to detect significant tumors in time, submitting patients to minimal psychological and physical burden, especially in men with high serum PSA and repeat biopsies. We aimed to determine long-term outcomes with respect to ANNA/C-TRUS ability to detect PCa with six targeted biopsies.

METHODS

A subset of 71 patients were enrolled. During monitoring, they were subjected to primary, secondary, or even multiple prostate biopsies when needed. Protocol monitoring included PSA measurements, digital rectal examination (DRE) and imaging.

RESULTS

The median follow-up was 12 years. Forty-one patients had a history of negative systematic random biopsies (1-3 sessions). Their age ranges 62-85 years, PSA 0.5-47.3 ng/ml, and the median prostate volume 11-255 cc. During monitoring, 15 patients were diagnosed with PCa. Only two harbored aggressive tumors. The median time to diagnosis was 6 years. All PCa patients are free from biochemical relapse. From the remaining 56 patients, 11 did not have any biopsies, 12 had one, 13 had two, and 20 had three or more biopsy sessions.

CONCLUSIONS

ANNA/C-TRUS is a useful method monitoring patients with a risk of PCa. 50-75% of the usually performed biopsy cores could be spared and, after 12 years, 97% of the patients were either without evidence of a PCa or were diagnosed with a good prognosis tumor.