Association of preoperative urethral parameters on magnetic resonance imaging and immediate recovery of continence following Retzius-sparing robot-assisted radical prostatectomy

Background

Studies regarding predictive factors of urinary continence following Retzius-sparing radical prostatectomy (RP) is limited. This study was designed to evaluate association of urethral parameters on preoperative magnetic resonance imaging (MRI) and immediate recovery of urinary continence following Retzius-sparing robot assisted radical prostatectomy (RS-RARP).

Methods

This retrospective cohort study enrolled 156 patients with clinically localized prostate cancer who underwent MRI before RS-RARP. We measured the following structures on preoperative MRI: minimal residual membranous urethral length (mRUL), peri-urethral sphincter complex (PSC) thickness, urethral wall thickness (UWT), the thicknesses of the levator ani muscle (LAM) and obturator internus muscle (OIM). Immediate urinary continence was defined as patients reported freedom from using safety pad within 7 days after removal of urinary catheter. Patients were divided into two groups according the median of each parameter on MRI. We retrospectively analyzed the patients in term of preoperative clinical factors and postoperative urinary continence.

Results

A total of 100 patients (64.1%) reported immediate urinary continence after RS-RARP. Immediate urinary continence was significantly more in patients with longer mRUL (≥8.70 mm) than in patients with shorter mRUL (<8.70 mm; P=0.000). On multivariable analysis, longer mRUL was significantly related to immediate urinary continence after RS-RAPA (odds ratio 8.265; P=0.000). PSC, UWT, LAM and OIM were not associated with immediate urinary continence.

Conclusions

Our results firstly demonstrated that preoperative mRUL measured on MRI was an independent predictor of immediate urinary continence following RS-RARP. Therefore, preservation of membranous urethra is still the anatomical basis of better urinary outcome after RS-RARP.

Coronavirus disease 2019: a clinical review

In December 2019, an outbreak of coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was reported in Wuhan, China, and it subsequently spread in many countries around the world. Many efforts have been applied to control and prevent the spread of COVID-19, and many scientific studies have been conducted in a short period of time. Here we present an overview of the viral structure, pathogenesis, diagnosis, and clinical features of COVID-19 based on the current state of knowledge, and we compare its clinical characteristics with SARS and Middle East Respiratory Syndrome (MERS). Current researches on potentially effective treatment alternatives are discussed. We hope this review can help medical workers and researchers around the world contain the current COVID-19 pandemic.

Tumour location determined by preoperative MRI is an independent predictor for positive surgical margin status after Retzius-sparing robot-assisted radical prostatectomy

OBJECTIVE

To investigate the influence of tumour location zone on positive surgical margin (PSM) status after Retzius-sparing robot-assisted radical prostatectomy (RS-RARP).

MATERIALS AND METHODS

A total of 203 consecutive patients with prostate cancer (PCa) who underwent RS-RARP at our centre were divided into three cohorts according to the tumour zonal origin described on preoperative magnetic resonance imaging (MRI). Clinical and pathological characteristics were compared among the three groups. The associations of clinicopathological variables with PSM status after RS-RARP were also evaluated.

RESULTS

The rates of PSM in patients with transition zone (TZ) and mixed origin tumours were significantly higher than in patients with peripheral zone tumours (P < 0.01). Of the PSMs in patients with TZ and mixed origin cancers, 42.0% and 40.9%, respectively, were located at the anterior part of the gland. On multivariate analysis, presence of a TZ tumour was significantly associated with a higher PSM rate after RS-RARP (P < 0.01). Sub-analysis showed that high-risk patients with TZ tumours had a higher risk of PSM after RS-RARP (P < 0.01).

CONCLUSION

Presence of a TZ tumour is an independent risk factor for PSMs after RS-RARP. Preoperative identification of TZ tumours might aid surgical planning for the Retzius-sparing technique, especially in high-risk patients.

Comparison of 68Ga-prostate-specific membrane antigen (PSMA) positron emission tomography/computed tomography (PET/CT) and multi-parametric magnetic resonance imaging (MRI) in the evaluation of tumor extension of primary prostate cancer

Background

To compare the diagnostic performance of ⁶⁸Ga-prostate-specific membrane antigen positron emission tomography/computed tomography (⁶⁸Ga-PSMA PET/CT) with multi-parametric magnetic resonance imaging (mpMRI) on extracapsular extension (ECE) and seminal vesicle invasion (SVI) in primary prostate cancer and its impact on therapeutic decisions.

Methods

We retrospectively enrolled 54 patients with both PET/CT and mpMRI before radical prostatectomy. Diagnostic performance of mpMRI, PET/CT and their combination (com-MRI/PET) on ECE and SVI on a patient basis were analyzed. The impact of additional PET/CT scanning on therapeutic decisions were presented.

Results

Among the 54 patients, 17 had tumor limited in the prostate gland, 25 only had ECE and 12 patients had both SVI and ECE on pathology. The sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of ECE were 54%, 94%, 95%, 48% on mpMRI, 78%, 94%, 97%, 67% on PET/CT and 83%, 88%, 94%, 71% on com-MRI/PET. Both PET/CT and com-MRI/PET had a higher sensitivity than mpMRI on ECE diagnosis (78% vs. 54%, P<0.05 and 83% vs. 54%, P<0.05). No difference was observed between PET/CT and com-MRI/PET (78% vs. 83%, P=0.17). The Sensitivity, specificity, PPV and NPV of SVI were 67%, 93%, 72%, 91% on mpMRI, 75%, 95%, 82%, 93% on PET/CT and 75%, 88%, 64%, 93% on com-MRI/PET. No difference was found between the three scannings. After the additional evaluation of PET/CT, 18.5% (10/54) turned from nerve-sparing surgery to non-nerve sparing surgery.

Conclusions

⁶⁸Ga-PSMA PET/CT has a higher sensitivity on ECE detection than mpMRI but shows no superiority on SVI.

Current updates on the role of reactive oxygen species in bladder cancer pathogenesis and therapeutics

Bladder cancer (BCa) is the fourth most common urological malignancy in the world, it has become the costliest cancer to manage due to its high rate of recurrence and lack of effective treatment modalities. As a natural byproduct of cellular metabolism, reactive oxygen species (ROS) have an important role in cell signaling and homeostasis. Although up-regulation of ROS is known to induce tumorigenesis, growing evidence suggests a number of agents that can selectively kill cancer cells through ROS induction. In particular, accumulation of ROS results in oxidative stress-induced apoptosis in cancer cells. So, ROS is a double-edged sword. A modest level of ROS is required for cancer cells to survive, whereas excessive levels kill them. This review summarizes the up-to-date findings of oxidative stress-regulated signaling pathways and transcription factors involved in the etiology and progression of BCa and explores the possible therapeutic implications of ROS regulators as therapeutic agents for BCa.

Renal Pelvis Metastasis From Prostatic Adenocarcinoma Missed by PSMA PET: A Case Report

Metastasis of prostate cancer to renal pelvis is extremely rare. A 64-year-old man was hospitalized for increased prostate-specific antigen after radical prostatectomy. ⁶⁸Ga-PSMA-11 PET/CT showed hydronephrosis caused by a mass in the left renal pelvis without significant uptake of prostate-specific membrane antigen tracer. The histopathology indicated metastatic prostate cancer with a Gleason score of 5 + 5 but negative for prostate-specific membrane antigen following nephroureterectomy. Although metastasis to renal pelvis is rare, the occurrence possibility could not be ignored when with hydronephrosis is found in prostate cancer patients.

Feasibility of three-dimensional constructive interference in steady state sequences for evaluating the anterolateral ligament

AIM

The purpose of the study was to determine the feasibility of three-dimensional (3D) constructive interference in steady state (CISS) sequences for evaluating the anterolateral ligament (ALL).

MATERIALS AND METHODS

Magnetic resonance imaging (MRI) of the right knee joint in 30 healthy volunteers was performed using a 3 T MRI machine. Axial T2-weighted imaging with fat saturation (T2WI-FS), coronal proton-density-weighted imaging with fat saturation (PDWI-FS), and 3D-CISS were included in the protocol. Multiplanar reconstruction (MPR) and rotating stretched curved planar reconstructions (CPRs) of the ALL at 30°, 60°, 90°, 120°, and 150° were generated from the 3D-CISS images. The visibility of the femoral part, meniscal part, tibial part, meniscal insertion, femoral footprint, and tibial footprint of the ALL on the imaging of all sequences was recorded.

RESULTS

Based on the CPR of 3D-CISS MRI, the presence of tibial and femoral footprints of the ALL was rated superior to MPR and PDWI-FS (96.67% and 96.67%, respectively; p<0.017). Rotating CPR of 3D-CISS MRI imaging was rated superior to PDWI-FS with respect to the tibial part, meniscal part, and meniscal insertion of the ALL (96.67%, 83.33%, and 83.33%, respectively; p<0.05). Rotating CPR of 3D-CISS MRI was rated superior to PDWI-FS with respect to the femoral part of the ALL, but the difference was not statistically significant (p=0.095). The angle between the ALL and lateral collateral ligament (LCL) on the oblique sagittal image was 18.34±1.88°.

CONCLUSIONS

The MRI 3D-CISS sequences significantly enhanced the ability to identify the ALL compared to the 2D MRI sequences.

Diagnostic challenge for giant left retroperitoneal accessory spleen: a case report

An accessory spleen refers to single or multiple splenic tissues that appear outside the normal spleen position and have structures and functions similar to those of a normal spleen. We herein present a rare case of a 31-year-old woman who was hospitalized because of a 14-year history of sudden left upper abdominal pain after running. Abdominal computed tomography suggested a large soft tissue mass at the left renal hilum surrounded by several enlarged lymph nodes, which was totally different from computed tomography scanning of normal accessory spleen. The mass was resected by robot-assisted laparoscopic surgery. Histopathological examination confirmed the diagnosis of accessory spleen. The incidence of retroperitoneal accessory spleen is very rare, which should be differentiated with retroperitoneal tumors.

PSMA uptake on [68Ga]-PSMA-11-PET/CT positively corrects with prostate cancer aggressiveness

BACKGROUND

Conflict results has been revealed on the relationship between PSMA uptake values (SUVs) on PSMA PET/CT and prostate cancer aggressiveness. This study is to validate the relationship between SUVs with prostate cancer (PCa) aggressiveness and its role in evaluation of clinically significant PCa (csPCa) and risk stratification.

METHODS

We retrospectively enrolled 51 patients who underwent [68Ga]-PSMA PET/CT (PET/CT) before radical prostatectomy (RP). PET/CT results were corrected with whole mount histology. The relationship between SUVs and aggressiveness related indictors including Gleason score, T stage, initial PSA and tumor size were analyzed. The cutoff value for detection of overall PCa, csPCa and intermediate/high-risk PCa were calculated by receiver operating characteristics (ROC) analysis.

RESULTS

Both SUVmax and SUVmean positively correlated with Gleason score (SUVmax Spearman r=0.546 p<0.01, SUVmean Spearman r=0.359 p<0.01), PSA level (SUVmax Spearman r=0.568 p<0.01, SUVmean Spearman r=0.529 p<0.01) and tumor volume (SUVmax Spearman r=0.635 p<0.01, SUVmean Spearman r=0.590 p<0.01). Tumors with T3 stage had significant higher SUV uptake than T2 (SUVmax 17.49 ± 10.50 vs 9.90 ± 8.7, p<0.01 and SUVmean 17.49 ± 10.50 vs 9.90 ± 8.7, p<0.01). ROC analysis showed cutoff of SUVmax (3.8) and SUVmean (2.8) for overall PCa detection. ROC analysis showed that csPCa and intermediate/high risk PCa had the same cutoff on both SUVmax (8.4) and SUVmean (6.8).

CONCLUSIONS

PSMA uptake on PSMA PET/CT positively correlated with Gleason score, T stage, initial PSA and tumor volume. Both SUVmax and SUVmean can be applied as parameters for csPCa detection and risk classification.

Search for Sterile Neutrinos in MINOS and MINOS+ Using a Two-Detector Fit

A search for mixing between active neutrinos and light sterile neutrinos has been performed by looking for muon neutrino disappearance in two detectors at baselines of 1.04 and 735 km, using a combined MINOS and MINOS+ exposure of 16.36×10^{20} protons on target. A simultaneous fit to the charged-current muon neutrino and neutral-current neutrino energy spectra in the two detectors yields no evidence for sterile neutrino mixing using a 3+1 model. The most stringent limit to date is set on the mixing parameter sin^{2}θ_{24} for most values of the sterile neutrino mass splitting Δm_{41}^{2}>10^{-4}  eV^{2}.

Revealing Color Forces with Transverse Polarized Electron Scattering

The Spin Asymmetries of the Nucleon Experiment measured two double spin asymmetries using a polarized proton target and polarized electron beam at two beam energies, 4.7 and 5.9 GeV. A large-acceptance open-configuration detector package identified scattered electrons at 40° and covered a wide range in Bjorken x (0.3<x<0.8). Proportional to an average color Lorentz force, the twist-3 matrix element, d[over ˜]_{2}^{p}, was extracted from the measured asymmetries at Q^{2} values ranging from 2.0 to 6.0  GeV^{2}. The data display the opposite sign compared to most quark models, including the lattice QCD result, and an unexpected scale dependence. Furthermore, when combined with the neutron data in the same Q^{2} range the results suggest a flavor independent average color Lorentz force.

Skeletal muscle mitoflashes, pH, and the role of uncoupling protein-3

Mitochondrial reactive oxygen species (ROS) are important cellular signaling molecules, but can cause oxidative damage if not kept within tolerable limits. An important proximal form of ROS in mitochondria is superoxide. Its production is thought to occur in regulated stochastic bursts, but current methods using mitochondrial targeted cpYFP to assess superoxide flashes are confounded by changes in pH. Accordingly, these flashes are generally referred to as 'mitoflashes'. Here we provide regulatory insights into mitoflashes and pH fluctuations in skeletal muscle, and the role of uncoupling protein-3 (UCP3). Using quantitative confocal microscopy of mitoflashes in intact muscle fibers, we show that the mitoflash magnitude significantly correlates with the degree of mitochondrial inner membrane depolarization and ablation of UCP3 did not affect this correlation. We assessed the effects of the absence of UCP3 on mitoflash activity in intact skeletal muscle fibers, and found no effects on mitoflash frequency, amplitude or duration, with a slight reduction in the average size of mitoflashes. We further investigated the regulation of pH flashes (pHlashes, presumably a component of mitoflash) by UCP3 using mitochondrial targeted SypHer (mt-SypHer) in skeletal muscle fibers. The frequency of pHlashes was significantly reduced in the absence of UCP3, without changes in other flash properties. ROS scavenger, tiron, did not alter pHlash frequency in either WT or UCP3KO mice. High resolution respirometry revealed that in the absence of UCP3 there is impaired proton leak and Complex I-driven respiration and maximal coupled respiration. Total cellular production of hydrogen peroxide (H₂O₂) as detected by Amplex-UltraRed was unaffected. Altogether, we demonstrate a correlation between mitochondrial membrane potential and mitoflash magnitude in skeletal muscle fibers that is independent of UCP3, and a role for UCP3 in the control of pHlash frequency and of proton leak- and Complex I coupled-respiration in skeletal muscle fibers. The differential regulation of mitoflashes and pHlashes by UCP3 and tiron also indicate that the two events, though may be related, are not identical events.

Regeneration of a neoartery through a completely autologous acellular conduit in a minipig model: a pilot study

Background

Vascular grafts are widely used as a treatment in coronary artery bypass surgery, hemodialysis, peripheral arterial bypass and congenital heart disease. Various types of synthetic and natural materials were experimented to produce tissue engineering vascular grafts. In this study, we investigated in vivo tissue engineering technology in miniature pigs to prepare decellularized autologous extracellular matrix-based grafts that could be used as vascular grafts for small-diameter vascular bypass surgery.

Methods

Autologous tissue conduits (3.9 mm in diameter) were fabricated by embedding Teflon tubings in the subcutaneous pocket of female miniature pigs (n = 8, body weight 25–30 kg) for 4 weeks. They were then decellularized by CHAPS decellularization solution. Heparin was covalently-linked to decellularized tissue conduits by Sulfo-NHS/EDC. We implanted these decellularized, completely autologous extracellular matrix-based grafts into the carotid arteries of miniature pigs, then sacrificed the pigs at 1 or 2 months after implantation and evaluated the patency rate and explants histologically.

Results

After 1 month, the patency rate was 100% (5/5) while the inner diameter of the grafts was 3.43 ± 0.05 mm (n = 5). After 2 months, the patency rate was 67% (2/3) while the inner diameter of the grafts was 2.32 ± 0.14 mm (n = 3). Histological staining confirmed successful cell infiltration, and collagen and elastin deposition in 2-month samples. A monolayer of endothelial cells was observed along the inner lumen while smooth muscle cells were dominant in the graft wall.

Conclusion

A completely autologous acellular conduit with excellent performance in mechanical properties can be remodeled into a neoartery in a minipig model. This proof-of-concept study in the large animal model is very encouraging and indicates that this is a highly feasible idea worthy of further study in non-human primates before clinical translation.

Engineered Microenvironment for Manufacturing Human Pluripotent Stem Cell-Derived Vascular Smooth Muscle Cells

Human pluripotent stem cell-derived vascular smooth muscle cells (hPSC-VSMCs) are of great value for disease modeling, drug screening, cell therapies, and tissue engineering. However, producing a high quantity of hPSC-VSMCs with current cell culture technologies remains very challenging. Here, we report a scalable method for manufacturing hPSC-VSMCs in alginate hydrogel microtubes (i.e., AlgTubes), which protect cells from hydrodynamic stresses and limit cell mass to <400 μm to ensure efficient mass transport. The tubes provide cells a friendly microenvironment, leading to extremely high culture efficiency. We have shown that hPSC-VSMCs can be generated in 10 days with high viability, high purity, and high yield (∼5.0 × 108 cells/mL). Phenotype and gene expression showed that VSMCs made in AlgTubes and VSMCs made in 2D cultures were similar overall. However, AlgTube-VSMCs had higher expression of genes related to vasculature development and angiogenesis, and 2D-VSMCs had higher expression of genes related to cell death and biosynthetic processes.

Contribution of bone marrow-derived cells to in situ engineered tissue capsules in a rat model of chronic kidney disease

Tissue engineered blood vessels (TEBVs) hold great promise for clinical use in patients with end stage renal disease (ESRD) requiring vascular access for hemodialysis. A promising way to make TEBVs is to exploit foreign body response (FBR) of polymeric rods used as templates. However, since the FBR predominantly involves bone-marrow (BM) derived cells and ESRD coincides with impaired function of BM, it is important to assess the generation of TEBVs in conditions of renal failure. To this end, we implanted polymer rods in the subcutis of rats after BM-transplantation with GFP-labeled BM cells in a model of chronic kidney disease (CKD). At 3 weeks after implantation, rods were encapsulated by tissue capsule (TC) composed of collagen, myofibroblasts and macrophages. On average, 13% of CD68⁺ macrophages were GFP⁺, indicating BM origin. Macrophage-to-myofibroblasts differentiation appeared to play an important role in TC formation as 26% of SMA⁺/GFP⁺ myofibroblasts co-expressed the macrophage marker CD68. Three weeks after rod implantation, the cellular response changed towards tissue repair, characterized by 40% increase in CD68⁺/CD163⁺ repair associated macrophages and 95% increase in TGFβ and IL10 gene expression as compared to TCs harvested at 1 week. These results show that both BM derived and tissue resident cells, contribute to TC formation, whereas macrophages serve as precursors of myofibroblasts in mature TCs. Finally, the presence of CKD did not significantly alter the process of TC formation, which holds the potential to support our approach for future clinical use in ESRD patients.

Accuracy of interferon-γ-induced protein 10 for diagnosing latent tuberculosis infection: a systematic review and meta-analysis

BACKGROUND

Effective diagnostic methods for detecting latent tuberculosis infection (LTBI) are important for its eradication. A number of studies have evaluated the use of interferon-γ-induced protein 10 (IP-10), which is elevated after tuberculosis infection, as a biomarker for LTBI, but conclusive results regarding its effectiveness have not been reported.

OBJECTIVES

Our objective was to assess the diagnostic value of IP-10 for LTBI.

DATA SOURCES

We searched the PubMed, Embase, the Cochrane Library and Web of Science databases to find eligible studies.

STUDY ELIGIBILITY CRITERIA

We included cohort, case-control and cross-sectional studies that evaluated IP-10 in LTBI participants in comparison with tuberculin skin tests (TST) and interferon-γ release assays (IGRA).

PARTICIPANTS

Individuals with LTBI and uninfected participants.

INTERVENTIONS

IP-10 (index test) compared with TST and IGRA (reference standard) for diagnosing LTBI.

METHODS

PubMed, Embase, the Cochrane Library, and Web of Science databases were searched up to June 2018. A hierarchical summary receiver operating characteristic (HSROC) model was used to evaluate the pooled sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), diagnostic odds ratio (DOR), and HSROC curve for the diagnostic efficiency of IP-10.

RESULTS

Twelve studies including 1023 participants and 1122 samples were included. The overall pooled sensitivity was 0.85 (95% CI 0.80-0.88), specificity was 0.89 (95% CI 0.84-0.92), PLR was 7.55 (95% CI 5.20-10.97), NLR was 0.17 (95% CI 0.13-0.22) and DOR was 44.23 (95% CI 28.86-67.79), indicating a high accuracy for diagnosing LTBI. Based on a meta-regression analysis, high-burden countries, study design, IP-10 method, reference standard and the IP-10 cut-off could not explain the heterogeneity (p >0.05).

CONCLUSIONS

Our results suggested that IP-10 is a promising biomarker for the diagnosis of LTBI.

Combination of 68Ga-PSMA PET/CT and Multiparametric MRI Improves the Detection of Clinically Significant Prostate Cancer: A Lesion-by-Lesion Analysis

Our purpose was to explore whether ⁶⁸Ga-PSMA PET/CT alone (PET/CT) or in combination with multiparametric MRI (PET/MRI) can improve the detection of clinically significant prostate cancer (PCa). Methods: We retrospectively enrolled 54 patients who underwent both MRI and PET/CT before radical prostatectomy. Regions of interest on MR images, PET/CT images, and pathologic images were marked. A lesion was defined as a region of interest marked on images obtained with any of the 3 modalities. All lesions were characterized using the prostate imaging reporting and data system (PI-RADS), the molecular imaging PSMA expression score, and the pathologic results and analyzed. Diagnostic performance was analyzed by receiver-operating-characteristic analysis. Specific improvement for lesions with different PI-RADS scores was analyzed using the net reclassification index (NRI). Results: In total, 90 lesions from 54 patients were analyzed, among which 66 lesions represented clinically significant PCa. Receiver-operating-characteristic analysis showed PET/MRI to perform better than MRI in detecting clinically significant PCa (change in area under the curve, 0.06; 95% confidence interval, 0.01-0.12; P < 0.05). With the calculated cutoff, PET/MRI performed significantly better than MRI (NRI, 21.9%; P < 0.01), with an improvement in sensitivity (89% vs. 76%, P < 0.01) at no sacrifice of specificity (96% vs. 88%, P > 0.05). Improvement in diagnosing clinically significant PCa occurred for lesions classified as PI-RADS 3 (NRI, 66.7%; P < 0.01). Conclusion: PET/MRI improves the detection of clinically significant PCa for PI-RADS 3 lesions.

Primary Extrarenal Type 2 Papillary Renal Cell Carcinoma: A Case Report

Type 2 papillary renal cell carcinoma (PRCC) is a malignant tumor originated from renal tubular epithelial cells. Here we present a rare case of extrarenal type 2 PRCC which is located at the right lateral side of the retroperitoneal inferior vena cava. No suspicious lesions were detected in the bilateral kidneys. The diagnosis was confirmed by histopathological examination after complete excision of the tumor. No recurrence was observed in 5 months of follow-up after surgery.