Shear-wave elastography to predict hepatocellular carcinoma after hepatitis C virus eradication:A systematic review and meta-analysis

BACKGROUND Direct-acting antiviral agents(DAAs)are highly effective treatment for chronic hepatitis C(CHC)with a significant rate of sustained virologic response(SVR).The achievement of SVR is crucial to prevent additional liver damage and slow down fibrosis progression.The assessment of fibrosis degree can be performed with transient elastography,magnetic resonance elastography or shear-wave elastography(SWE).Liver elastography could function as a predictor for hepato-cellular carcinoma(HCC)in CHC patients treated with DAAs.AIM To explore the predictive value of SWE for HCC development after complete clearance of hepatitis C virus(HCV).METHODS A comprehensive literature search of clinical studies was performed to identify the ability of SWE to predict HCC occurrence after HCV clearance.In accordance with the study protocol,a qualitative and quantitative analysis of the evidence was planned.RESULTS At baseline and after 12 wk of follow-up,a trend was shown towards greater liver stiffness(LS)in those who go on to develop HCC compared to those who do not[baseline LS standardized mean difference(SMD):1.15,95%confidence interval(95%CI):020-2.50;LS SMD after 12 wk:0.83,95%CI:0.33-1.98].The absence of a statistically significant difference between the mean LS in those who developed HCC or not may be related to the inability to correct for confounding factors and the absence of raw source data.There was a statist-ically significant LS SMD at 24 wk of follow-up between patients who developed HCC vs not(0.64;95%CI:0.04-1.24).CONCLUSION SWE could be a promising tool for prediction of HCC occurrence in patients treated with DAAs.Further studies with larger cohorts and standardized timing of elastographic evaluation are needed to confirm these data.

Dynamic contrast enhanced ultrasound in differential diagnosis of hepatocellular carcinoma: A systematic review and meta-analysis

BACKGROUND Non-invasive differential diagnosis between hepatocellular carcinoma(HCC)and other liver cancer(i.e.cholangiocarcinoma or metastasis)is highly challenging and definitive diagnosis still relies on histological exam.The patterns of enhancement and wash-out of liver nodules can be used to stratify the risk of malignancy only in cirrhotic patients and HCC frequently shows atypical features.Dynamic contrast-enhanced ultrasound(DCEUS)with standardized software could help to overcome these obstacles,providing functional and quantitative parameters and potentially improving accuracy in the evaluation of tumor perfusion.AIM To explore clinical evidence regarding the application of DCEUS in the differential diagnosis of liver nodules.METHODS A comprehensive literature search of clinical studies was performed to identify the parameters of DCEUS that could relate to histological diagnosis.In accordance with the study protocol,a qualitative and quantitative analysis of the evidence was planned.RESULTS Rise time was significantly higher in HCC patients with a standardized mean difference(SMD)of 0.83(95%CI:0.48-1.18).Similarly,other statistically significant parameters were mean transit time local with a SMD of 0.73(95%CI:0.20-1.27),peak enhancement with a SMD of 0.37(95%CI:0.03-0.70),area wash-in area under the curve with a SMD of 0.47(95%CI:0.13-0.81),wash-out area under the curve with a SMD of 0.55(95%CI:0.21-0.89)and wash-in and wash-out area under the curve with SMD of 0.51(95%CI:0.17-0.85).SMD resulted not significant in fall time and wash-in rate,but the latter presented a trend towards greater values in HCC compared to intrahepatic cholangiocarcinoma.CONCLUSION DCEUS could improve non-invasive diagnosis of HCC,leading to less liver biopsy and early treatment.This quantitative analysis needs to be applied on larger cohorts to confirm these preliminary results.

Portal vein thrombosis in cirrhosis: Why a well-known complication is still matter of debate

Portal vein thrombosis(PVT)represents a well-known complication during the natural course of liver cirrhosis(LC),ranging from asymptomatic cases to lifethreating conditions related to portal hypertension and hepatic decompensation.Portal flow stasis,complex acquired hypercoagulable disorders and exogenous factors leading to endothelial dysfunction have emerged as key factors for PVT development.However,PVT occurrence remains unpredictable and many issues regarding its natural history,prognostic significance and treatment are still elusive.In particular although spontaneous resolution or disease stability occur in most cases of PVT,factors predisposing to disease progression or recurrence after spontaneous recanalization are not clarified as yet.Moreover,PVT impact on LC outcome is still debated,as PVT may represent itself a consequence of liver fibrosis and hepatic dysfunction progression.Anticoagulation and transjugular intrahepatic portosystemic shunt are considered safe and effective in this setting and are recommended in selected cases,even if the safer therapeutic option and the optimal therapy duration are still unknown.Nevertheless,their impact on mortality rates should be addressed more extensively.In this review we present the most debated questions regarding PVT,whose answers should come from prospective cohort studies and large sample-size randomized trials.

Diagnosis of bowel diseases:The role of imaging and ultrasonography

Examinations with a visualisation of the anatomy and pathology of the gastrointestinal(GI) tract are often necessary for the diagnosis of GI diseases.Traditional radiology played a crucial role for many years.Endoscopy,despite some limitations,remains the main technique in the differential diagnosis and treatment of GI diseases.In the last decades,the introduction of,and advances in,non-invasive cross-sectional imaging modalities,including ultrasound(US),computed tomography(CT),positron-emission tomography(PET),and magnetic resonance imaging,as well as improvements in the resolution of imaging data,the acquisition of 3D images,and the introduction of contrast-enhancement,have modified the approach to the examination of the GI tract.Moreover,additional co-registration techniques,such as PET-CT and PET-MRI,allow multimodal data acquisition with better sensitivity and specificity in the study of tissue pathology.US has had a growing role in the development and application of the techniques for diagnosis and management of GI diseases because it is inexpensive,non-invasive,and more comfortable for the patient,and it has sufficient diagnostic accuracy toprovide the clinician with image data of high temporal and spatial resolution.Moreover,Doppler and contrastenhanced ultrasound(CEUS) add important information about blood flow.This article provides a general review of the current literature regarding imaging modalities used for the evaluation of bowel diseases,highlighting the role of US and recent developments in CEUS.

Usefulness of contrast enhanced ultrasound in monitoring therapeutic response after hepatocellular carcinoma treatment

In the last years, the development in the oncology field has been huge and rapid. In particular, the evaluation of response to anti-tumour treatments has been being object of intense research, producing significant changes. Response assessment after therapy in solid neoplasias has always used radiological imaging techniques, with tumour size reduction representing a presumed therapeutic efficacy. However, with the introduction of anti-angiogenetic drugs the evaluation of tumour size has become unsuitable because some tumours, under treatment, show only tumour perfusion changes rather than lesion shrinkage. Between different imaging techniques with contrast-enhancement, contrastenhanced ultrasound(CEUS) and, in particular, dynamic CEUS have arisen as a promising and non-invasive device for monitoring cancer treatments. Moreover, the introduction of perfusion software has even more refined the technique since it is able to provide quantitative parameters related to blood flow and blood volume that can be associated with tumour response and clinical outcome such as the progression free survival and the overall survival. Here, we give an overview of the current status of CEUS in monitoring hepatocellular carcinoma response to different kind of treatments.

Elastography as a predictor of liver cirrhosis complications after hepatitis C virus eradication in the era of direct-acting antivirals

Chronic inflammation due to hepatitis C virus(HCV)infection leads to liver fibrosis and rearrangement of liver tissue,which is responsible for the development of portal hypertension(PH)and hepatocellular carcinoma(HCC).The advent of direct-acting antiviral drugs has revolutionized the natural history of HCV infection,providing an overall eradication rate of over 90%.Despite a significant decrease after sustained virological response(SVR),the rate of HCC and liver-related complications is not completely eliminated in patients with advanced liver disease.Although the reasons are still unclear,cirrhosis itself has a residual risk for the development of HCC and other PH-related complications.Ultrasound elastography is a recently developed non-invasive technique for the assessment of liver fibrosis.Following the achievement of SVR,liver stiffness(LS)usually decreases,as a consequence of reduced inflammation and,possibly,fibrosis.Recent studies emphasized the application of LS assessment in the management of patients with SVR in order to define the risk for developing the complications of chronic liver disease(functional decompensation,gastrointestinal bleeding,HCC)and to optimize long-term prognostic outcomes in clinical practice.

Dynamic contrast enhanced ultrasound in gastrointestinal diseases:A current trend or an indispensable tool?

Contrast enhanced ultrasound(CEUS)has been widely implemented in clinical practice because of the enormous quantity of information it provides,along with its low cost,reproducibility,minimal invasiveness,and safety of the secondgeneration ultrasound contrast agents.To overcome the limitation of CEUS given by the subjective evaluation of the contrast enhancement behaviour,quantitative analysis of contrast kinetics with generation of time-intensity curves has been introduced in recent years.The quantification of perfusion parameters[named as dynamic-CEUS(D-CEUS)]has several applications in gastrointestinal neoplastic and inflammatory disorders.However,the limited availability of large studies and the heterogeneity of the technologies employed have precluded the standardisation of D-CEUS,which potentially represents a valuable tool for clinical practice in management of gastrointestinal diseases.In this article,we reviewed the evidence exploring the application of D-CEUS in gastrointestinal diseases,with a special focus on liver,pancreas,and inflammatory bowel diseases.