Comparative study of conventional US, contrast enhanced US and enhanced MR for the follow-up of prostatic radiofrequency ablation

Contrast-Enhanced Ultrasonography (CEUS) in Imaging of the Reproductive System in Dogs: A Literature Review

The use of contrast-enhanced ultrasound (CEUS) has been widely reported for reproductive imaging in humans and animals. This review aims to analyze the utility of CEUS in characterizing canine reproductive physiology and pathologies. In September 2022, a search for articles about CEUS in canine testicles, prostate, uterus, placenta, and mammary glands was conducted on PubMed and Scopus from 1990 to 2022, showing 36 total results. CEUS differentiated testicular abnormalities and neoplastic lesions, but it could not characterize tumors. In prostatic diseases, CEUS in dogs was widely studied in animal models for prostatic cancer treatment. In veterinary medicine, this diagnostic tool could distinguish prostatic adenocarcinomas. In ovaries, CEUS differentiated the follicular phases. In CEH-pyometra syndrome, it showed a different enhancement between endometrium and cysts, and highlighted angiogenesis. CEUS was shown to be safe in pregnant dogs and was able to assess normal and abnormal fetal-maternal blood flow and placental dysfunction. In normal mammary glands, CEUS showed vascularization only in diestrus, with differences between mammary glands. CEUS was not specific for neoplastic versus non-neoplastic masses and for benign tumors, except for complex carcinomas and neoplastic vascularization. Works on CEUS showed its usefulness in a wide spectrum of pathologies of this non-invasive, reliable diagnostic procedure.

Potential Mechanisms of Pyrrosiae Folium in Treating Prostate Cancer Based on Network Pharmacology and Molecular Docking

Objective The network pharmacology approach and molecular docking were employed to explore the mechanism of Pyrrosiae Folium(PF) against prostate cancer (PCa). Methods The active compounds and their corresponding putative targets of PF were identified by the Traditional Chinese Medicine Systems Pharmacology (TCMSP), the gene names of the targets were obtained from the UniProt database. The collection of genes associated with PCa were obtained from GeneCards and DisGeNET database. We merged the drug targets and disease targets by online software, Draw Venn Diagram. The resulting gene list was imported into R software (v3.6.3) for GO and KEGG function enrichment analysis. The STRING database was utilized for protein-protein interaction (PPI) network construction. The cytoHubba plugin of Cytoscape was used to identify core genes. Further, molecular docking analysis of the hub targets were carried out using AutoDock Vina software (v1.5.6). Results A total of 6 active components were screened by PF, with 167 corresponding putative targets, 1395 related targets for PCa, and 113 targets for drugs and diseases. The "drug-component-disease-target" network was constructed by Cytoscape software and the target genes mainly involved in the complex treating effects associated with response to oxidative stress, cytokine activity, pathways in cancer, prostate cancer pathway and TNF signaling pathway. Core genes in the PPI network were TNF, JUN, IL6, IL1B, CXCL8, RELA, CCL2, TP53, IL10 and FOS. The molecular docking results reveal the better binding affinity of 6 active components to the core targets. Conclusion The results of this study indicated that PF may be have a certain anti-PCa effect by regulating related target genes, affecting Pathways in cancer, TNF signaling pathway, Hepatitis B signaling pathway.

Molecular imaging of orthotopic prostate cancer with nanobubble ultrasound contrast agents targeted to PSMA

Ultrasound imaging is routinely used to guide prostate biopsies, yet delineation of tumors within the prostate gland is extremely challenging, even with microbubble (MB) contrast. A more effective ultrasound protocol is needed that can effectively localize malignancies for targeted biopsy or aid in patient selection and treatment planning for organ-sparing focal therapy. This study focused on evaluating the application of a novel nanobubble ultrasound contrast agent targeted to the prostate specific membrane antigen (PSMA-targeted NBs) in ultrasound imaging of prostate cancer (PCa) in vivo using a clinically relevant orthotopic tumor model in nude mice. Our results demonstrated that PSMA-targeted NBs had increased extravasation and retention in PSMA-expressing orthotopic mouse tumors. These processes are reflected in significantly different time intensity curve (TIC) and several kinetic parameters for targeted versus non-targeted NBs or LUMASON MBs. These, may in turn, lead to improved image-based detection and diagnosis of PCa in the future.

Dynamic prostatic and laser-ablated lesion volume change after transperineal laser ablation in canine: preliminary observation and its clinical significance

AIM

The purpose of this study is to observe the volume change of prostate and laser-ablated lesions in the canine and to explore the mechanism and clinical significance through histopathology.

MATERIALS AND METHODS

Transperineal laser ablation (TPLA) was performed under the guidance of transrectal ultrasound (TRUS) in eight canines. Two canines were sacrificed 1 day and 1 week after TPLA, respectively. The remaining six canines were sacrificed after finishing transrectal contrast-enhanced ultrasound (TR-CEUS) at three phases.

RESULTS

The prostatic volumes immediately following TPLA and 1 week later were larger than before TPLA (20.1 ± 3.9 vs 17.1 ± 3.8 ml; 21.7 ± 3.6 vs 17.1 ± 3.8 ml, p < 0.05), but 1 month later, returned to the preoperative level (17.4 ± 3.2 ml). At three time points, the mean volumes of laser-ablated lesions at 3 W/600 J were 0.6 ± 0.2, 1.1 ± 0.4, and 1.7 ± 0.5 ml, respectively, while those of laser-ablated lesions at 3 W/1200 J were 1.2 ± 0.2, 1.6 ± 0.3, and 2.2 ± 0.5 ml, respectively. The mean volumes of laser-ablated lesions increased significantly over time after TPLA (p < 0.050).

CONCLUSION

The prostate volume transient enlarges after TPLA, which prompts for clinical application that it should prolong appropriately the duration of urinary catheterization to avoid acute urinary retention. Many inflammatory cells were observed in the laser-ablated lesions and adjacent normal prostate parenchyma through histopathology. It is speculated that the inflammatory response is involved in the progression of tissue damage.

A pilot study of the shapes of ablation lesions in the canine prostate by laser, radiofrequency and microwave and their clinical significance

To explore the shape characteristics of ablation lesions created via laser ablation (LA), radiofrequency ablation (RFA) and microwave ablation (MWA) in canine prostates and the clinical significance of these characteristics, six adult male beagles were randomly assigned to the LA, RFA, and MWA groups. These ablations were performed with common parameters applied in clinical practice (LA, 3 W/1200 J; RFA and MWA, 30 W/120 s). One ablation lesion was created in each lobe of the prostate via the ablation technique, resulting in a total of twelve ablation lesions. Transrectal ultrasound (TRUS) was used as guidance during puncture and to monitor changes in the ablation lesions. Finally, the ablation efficacy was assessed using transrectal contrast-enhanced ultrasonography (CEUS), and the transverse diameter (TRD), anteroposterior diameter (APD) and longitudinal diameter (LD) of each ablation lesion were measured. The volume (V) and the ratio (R) value were calculated. R reflects the shape characteristic of the ablation lesion (the R value close to 1.0 indicates a more spherical shape). The R values of the ablation lesions were 0.89 ± 0.02, 0.72 ± 0.01, and 0.65 ± 0.03 for RFA, MWA and LA, respectively, and they were significantly different (P = 0.027). The volumes of the ablation lesions were 2.17 ± 0.10 ml, 1.51 ± 0.20 ml, and 0.79 ± 0.07 ml for MWA, LA and RFA, respectively, and they were also significantly different (P = 0.001). The three abovementioned thermal ablation techniques with common parameters in clinical practice can be used for ablation in the prostate. The shapes and volumes of the ablation lesions of the three techniques were varied: The RFA-created lesions had the lowest volumes and were more spherical in shape, demonstrating that RFA could be used for the treatment of relatively small lesions or tumours adjacent to vital organs. The MWA lesions had the largest size with a spherical shape, which could be advantageous for the ablation of tumours with relatively large sizes. The sizes of the ablation lesions created via LA were between those of RFA and MWA but presented more oval in shape, suggesting that this method is highly appropriate for the ablation of benign prostatic hyperplasia (BPH).

CEUS examination of the outcome of radiofrequency ablation of canine prostate lesions

Purpose: To determine the feasibility of using contrast-enhanced ultrasonography (CEUS) to dynamically examine the scope and development of radiofrequency ablation (RFA) lesions in the canine prostate.Material and methods: Ten male canines were divided into two groups of five canines each: the 1 week after the RFA group and the 1 month after the RFA group. RFA was performed on one side of the prostate in each canine. For the 1 month after the RFA group, the other side of the prostate underwent RFA prior to euthanasia, and the RFA lesion on this side was included as the immediate RFA group. The RFA lesion volume was measured by CEUS. The evaluation efficacy of CEUS for prostate RFA lesions was determined and compared with the pathological measurements.Results: In the immediately after RFA group, 1 week after RFA group, and 1 month after RFA group, the RFA lesion volumes were 0.77 ± 0.34, 1.11 ± 0.61, and 0.19 ± 0.09 cm³, as measured by CEUS; the volumes measured by pathology at the corresponding time points were 0.85 ± 0.28, 0.96 ± 0.31, and 0.20 ± 0.06 cm³, respectively. CEUS accurately assessed the RFA lesions at all the time points, and the measurement results were not significantly different from those of the pathological results (p > .05).Conclusions: CEUS reflects the extent of prostate RFA lesions and dynamically shows their changes in blood flow perfusion.

MRI-guided, transrectal, intraprostatic steam application as potential focal therapeutic modality for prostatic diseases in a large animal translational model: A feasibility follow-up study

Parallel to establishment of diagnostic surveillance protocols for detection of prostatic diseases, novel treatment strategies should be developed. The aim of the present study is to evaluate the feasibility and possible side effects of transrectal, MRI-targeted intraprostatic steam application in dogs as an established large animal translational model for prostatic diseases in humans. Twelve healthy experimental, intact, male beagle dogs without evidence of prostatic pathology were recruited. An initial MRI examination was performed, and MRI-targeted steam was applied intraprostatically immediately thereafter. Serum levels of C-reactive protein (CRP), clinical and ultrasonographic examinations were performed periodically following the procedure to assess treatment effect. Four weeks after treatment, all dogs underwent follow-up MRI examinations and three needle-core biopsies were obtained from each prostatic lobe. Descriptive statistics were performed. MRI-guided intraprostatic steam application was successfully performed in the study population. The first day after steam application, 7/12 dogs had minimal signs of discomfort (grade 1/24 evaluated with the short-form Glasgow Composite Measure Pain Scale) and no dogs showed any sign of discomfort by day 6. CRP elevations were detected in 9/12 dogs during the first week post steam application. Mild to moderate T2 hyperintense intraparenchymal lesions were identified during follow-up MRI in 11/12 dogs four weeks post procedure. Ten of these lesions enhanced mild to moderately after contrast administration. Coagulative necrosis or associated chronic inflammatory response was detected in 80.6% (58/72) of the samples obtained. MRI-targeted intraprostatic steam application is a feasible technique and displays minimal side effects in healthy dogs as translational model for human prostatic diseases. This opens the possibility of minimally invasive novel treatment strategies for intraprostatic lesions.

Diagnostic value of contrast-enhanced ultrasound versus magnetic resonance imaging in extrahepatic cholangiocarcinoma

AIM

To compare the value of contrast-enhanced ultrasound and magnetic resonance imaging in the diagnosis of extrahepatic cholangiocarcinoma (EHCC).

METHODS

Forty-six patients with extrahepatic cholangiocarcinoma (ECHH group) diagnosed at our hospital from January 2015 to December 2017 were enrolled. Forty-six patients with extrahepatic bile duct stones (CBDS group) and 46 patients with pancreatic head carcinomas or duodenum papilla disease (PD group) were also included. All patients underwent B-mode ultrasonography (BUS), CEUS, and MRI. Using the pathological diagnosis as the "gold standard", the receiver operating characteristic (ROC) curves were plotted to compare the diagnostic efficacy (including diagnostic accuracy, sensitivity, specificity, positive predictive value, and negative predictive value) of the three examination methods for EHCC.

RESULTS

There was no significant difference between CEUS and MRI in the arterial phase (χ² = 1.105, P = 0.602). CEUS showed low enhancement in 86.96% and 100.00% of patients in the portal phase and delayed phase, respectively, which were significantly higher than those of MRI (13.04% and 13.04%, respectively; χ² = 50.261, 70.769; P = 0.000, 0.000). The ROC curve analysis showed that the area under the curve (AUC) of MRI and CEUS for the diagnosis of EHCC was higher that of BUS (0.924, 0.897 vs 0.690). The diagnostic accuracy, sensitivity, specificity, positive predictive value, and negative predictive value of BUS for EHCC were significantly lower than those of CEUS (χ² = 0.175, 0.066, 11.467, 37.260, 6.328; P = 0.000, 0.010, 0.001, 0.000, 0.012) and MRI (χ² = 0.227, 0.098, 13.378, 41.170, 9.082; P = 0.000, 0.002, 0.000, 0.000, 0.003). There was no significant difference in the diagnostic efficacy of CEUS and MRI for EHCC (χ² = 0.464, 0.383, 0.000, 0.001, 0.334; P = 0.496, 0.536, 1.000, 0.972, 0.563).

CONCLUSION

CEUS has high value in the diagnosis of EHCC and can be used as an important complement to MRI.