Contrast-enhanced ultrasound in the diagnosis of hepatocellular carcinoma

Optimizing US for HCC surveillance

Ultrasound is the primary imaging modality used for surveillance of patients at risk for HCC. In 2017, the American College of Radiology Liver Imaging Reporting and Data Systems (ACR LI-RADS) introduced US LI-RADS to standardize the performance, interpretation, and reporting of US for HCC surveillance, with the algorithm recently updated as LI-RADS US Surveillance v2024. The American Association for the Study of Liver Diseases (AASLD) recommends reporting both the examination-level LI-RADS US Category as well as the US Visualization Score. The US Category conveys the overall findings of the exam and primarily determines follow up recommendations. The US Visualization Score conveys the expected sensitivity of the test and stratifies patients into appropriate surveillance pathways. One of the goals of routine surveillance is the detection of HCC at an early, potentially curable stage. Therefore, optimizing US technique is of critical importance. Increasing North American and worldwide utilization of LI-RADS US Surveillance, which includes technical recommendations, through education and outreach will undoubtedly benefit patients undergoing US HCC surveillance.

The Clinical Utility of Liver-Specific Ultrasound Contrast Agents During Hepatocellular Carcinoma Imaging

Hepatocellular carcinoma (HCC) is the most common form of hepatic malignancy, with high mortality rates recorded globally. Early detection through clinical biomarkers, medical imaging and histological assessment followed by rapid intervention are integral for positive patient outcomes. Although contrast-enhanced computed tomography scans and magnetic resonance imaging are recognised as the reference standard for the diagnosis and staging of HCC in international guidelines, ultrasound (US) examination is recommended as a screening tool for patients at risk. Contrast-enhanced US (CEUS) elevates the standard of an US examination using US contrast agents (UCAs), capable of diagnosing focal liver lesions with high efficacy. Most UCAs are purely intravascular, offering clinicians a dynamic representation of a lesions' arterial phase vascular kinetics, which is seldom seen in such detail during computed tomography or magnetic resonance imaging assessments. Despite its benefits, there is incongruity between international societies on the role of CEUS in the HCC clinical pathway. The transient nature of pure blood-pool agents is suggested to be insufficient to justify CEUS as a primary modality due to the inability to consistently perform whole liver imaging, alongside disputes regarding its capabilities to differentiate HCC from intrahepatic cholangiocarcinoma. A sinusoidal phase UCA affords clinicians the opportunity to perform whole liver imaging through Kupffer cell uptake in addition to visualising lesion vascular kinetics in the arterial and portal venous phases. Therefore, the purpose of this review was to examine the role of CEUS in the HCC clinical pathway in its current practice and observe how a Kupffer cell sinusoidal phase UCA may supplement contemporary diagnostic techniques through a multi-modality, multi-agent approach.

Contrast-enhanced ultrasound-based AI model for multi-classification of focal liver lesions

BACKGROUND & AIMS

Accurate multi-classification is a prerequisite for appropriate management of focal liver lesions (FLLs). Ultrasound is the most common imaging examination but lacks accuracy. Contrast-enhanced ultrasound (CEUS) offers better performance but is highly dependent on operator experience. Therefore, we aimed to develop a CEUS-based artificial intelligence (AI) model for FLL multi-classification and evaluate its performance in multicenter clinical tests.

METHODS

Since January 2017 to December 2023, CEUS videos, immunohistochemical biomarkers and clinical information on solid FLLs >1 cm in adults were collected from 52 centers to build and test the model. The model was developed to classify FLLs into six types: hepatocellular carcinoma, hepatic metastasis, intrahepatic cholangiocarcinoma, hepatic hemangioma, hepatic abscess and others. First, Module-Disease, Module-Biomarker and Module-Clinic were built in training set A and a validation set. Then, three modules were aggregated as Model-DCB in training set B and an internal test set. Model-DCB performance was compared with CEUS and MRI radiologists in three external test sets.

RESULTS

In total 3,725 FLLs from 52 centers were divided into training set A (n = 2,088), the validation set (n = 592), training set B (n = 234), the internal test set (n = 110), and external test sets A (n = 113), B (n = 276) and C (n = 312). In external test sets A, B and C, Model-DCB achieved significantly better performance (accuracy from 0.85 to 0.86) than junior CEUS radiologists (0.59-0.73), and comparable performance to senior CEUS radiologists (0.79-0.85) and senior MRI radiologists (0.82-0.86). In multiple subgroup analyses on demographic characteristics, tumor characteristics and ultrasound devices, its accuracy ranged from 0.79 to 0.92.

CONCLUSIONS

CEUS-based Model-DCB provides accurate multi-classification of FLLs. It holds promise for a wide range of populations, especially those in remote areas who have difficulty accessing MRI.

CLINICAL TRIAL

NCT04682886.

IMPACT AND IMPLICATIONS

Ultrasound is the most common imaging examination for screening focal liver lesions (FLLs), but it lacks accuracy for multi-classification, which is a prerequisite for appropriate clinical management. Contrast-enhanced ultrasound (CEUS) offers better diagnostic performance but relies on the experience of radiologists. We developed a CEUS-based model (Model-DCB) that can help junior CEUS radiologists to achieve comparable diagnostic ability as senior CEUS radiologists and senior MRI radiologists. The combination of an ultrasound device, CEUS examination and Model-DCB means that even patients in remote areas can be accurately diagnosed through examination by junior radiologists.

Thermal ablation of hepatocellular carcinoma

Percutaneous treatment of hepatocellular carcinoma (HCC) by means of thermal ablation (TA) has been introduced in clinical guidelines as a potentially curative treatment for the early stages of the disease since the early 2000s. Due to its safety profile and cost-effectiveness, TA can be offered as a first-line treatment for patients with HCC smaller than 3 cm. Thermal ablative techniques are in fact widely available at many centres worldwide and include radiofrequency (RF) and microwave (MW) ablation, with the latter increasingly applied in clinical practice in the last decade. Pre-clinical studies highlighted, as potential advantages of MW-based ablation, the ability to achieve higher temperatures (>100°C) and larger ablation zones in shorter times, with less susceptibility to blood flow-induced heat sink effects. Despite these advantages, there is no evidence of superior overall survival in patients treated with MW as compared to those treated with RF ablation. Local control has been proven to be superior to MW ablation with a similar complication rate. It is expected that further improvement of TA results in the treatment of HCC will result from the refinement of guidance and monitoring tools and the careful assessment of ablation margins. Thermal ablative treatments may also be performed on nodules larger than 3 cm by applying multiple devices or combining percutaneous and intra-arterial approaches. The role of novel immunotherapy regimens in combination with ablation is also currently under evaluation in clinical trials, with several potential benefits. In this review, indications, technical principles, results, and future prospects of TA for the treatment of HCC will be examined.

Liquid biopsy for early detection of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is a highly prevalent and lethal cancer globally. Over 90% of HCC cases arise in the context of liver cirrhosis, and the severity of the underlying liver disease or advanced tumor stage at diagnosis significantly limits treatment options. Early diagnosis is crucial, and all guidelines stress the importance of screening protocols for HCC early detection as a public health objective. As serum biomarkers are not optimal for early diagnosis, liquid biopsy has emerged as a promising tool for diagnosis, prognostication, and patients' stratification for personalized therapy in various solid tumors, including HCC. While circulating tumor cells (CTCs) are better suited for personalized therapy and prognosis, cell-free DNA (cfDNA) and extracellular vesicle-based technologies show potential for early diagnosis, HCC screening, and surveillance protocols. Evaluating the added value of liquid biopsy genetic and epigenetic biomarkers for HCC screening is a key goal in translational research. Somatic mutations commonly found in HCC can be investigated in cfDNA and plasma exosomes as genetic biomarkers. Unique methylation patterns in cfDNA or cfDNA fragmentome features have been suggested as innovative tools for early HCC detection. Likewise, extracellular vesicle cargo biomarkers such as miRNAs and long non-coding RNAs may serve as potential biomarkers for early HCC detection. This review will explore recent findings on the utility of liquid biopsy for early HCC diagnosis. Combining liquid biopsy methods with traditional serological biomarkers could improve the overall diagnostic accuracy for early HCC detection.

Application of artificial intelligence in the diagnosis of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is a major cause of cancer-related deaths worldwide. This review explores the recent progress in the application of artificial intelligence (AI) in radiological diagnosis of HCC. The Barcelona Classification of Liver Cancer criteria guides treatment decisions based on tumour characteristics and liver function indicators, but HCC often remains undetected until intermediate or advanced stages, limiting treatment options and patient outcomes. Timely and accurate diagnostic methods are crucial for enabling curative therapies and improving patient outcomes. AI, particularly deep learning and neural network models, has shown promise in the radiological detection of HCC. AI offers several advantages in HCC diagnosis, including reducing diagnostic variability, optimising data analysis and reallocating healthcare resources. By providing objective and consistent analysis of imaging data, AI can overcome the limitations of human interpretation and enhance the accuracy of HCC diagnosis. Furthermore, AI systems can assist healthcare professionals in managing the increasing workload by serving as a reliable diagnostic tool. Integration of AI with information systems enables comprehensive analysis of patient data, facilitating more informed and reliable diagnoses. The advancements in AI-based radiological diagnosis hold significant potential to improve early detection, treatment selection and patient outcomes in HCC. Further research and clinical implementation of AI models in routine practice are necessary to harness the full potential of this technology in HCC management.

Bio-medical imaging (X-ray, CT, ultrasound, ECG), genome sequences applications of deep neural network and machine learning in diagnosis, detection, classification, and segmentation of COVID-19: a Meta-analysis & systematic review

This review investigates how Deep Machine Learning (DML) has dealt with the Covid-19 epidemic and provides recommendations for future Covid-19 research. Despite the fact that vaccines for this epidemic have been developed, DL methods have proven to be a valuable asset in radiologists' arsenals for the automated assessment of Covid-19. This detailed review debates the techniques and applications developed for Covid-19 findings using DL systems. It also provides insights into notable datasets used to train neural networks, data partitioning, and various performance measurement metrics. The PRISMA taxonomy has been formed based on pretrained(45 systems) and hybrid/custom(17 systems) models with radiography modalities. A total of 62 systems with respect to X-ray(32), CT(19), ultrasound(7), ECG(2), and genome sequence(2) based modalities as taxonomy are selected from the studied articles. We originate by valuing the present phase of DL and conclude with significant limitations. The restrictions contain incomprehensibility, simplification measures, learning from incomplete labeled data, and data secrecy. Moreover, DML can be utilized to detect and classify Covid-19 from other COPD illnesses. The proposed literature review has found many DL-based systems to fight against Covid19. We expect this article will assist in speeding up the procedure of DL for Covid-19 researchers, including medical, radiology technicians, and data engineers.

Ordered Labeling-Facilitated Electrochemical Assay of Alpha-Fetoprotein-L3 Ratio for Diagnosing Hepatocellular Carcinoma

Serum alpha fetoprotein (AFP) is a "gold-standard" biomarker for the diagnosis of hepatocellular carcinoma (HCC). Available pieces of evidence suggest that the ratio of AFP-L3 isoform in the total AFP may provide more accurate prediction for the incidence of HCC. In this work, we design an electrochemical aptasensor for high-accuracy assay of AFP-L3 ratio based on differentiated labeling of AFP isoforms in an orderly fashion. Specifically, total AFP is first captured by an AFP aptamer-functionalized electrode and labeled with quantum dots-functionalized DNA probes via mild reduction. Then, AFP-L3 isoform that strongly binds to Lens culinaris agglutinin is labeled with silver nanoparticles after the exonuclease-catalyzed removal of DNA probes. By tracing the electrochemical responses of quantum dots and silver nanoparticles, respectively, the amounts of total AFP and AFP-L3 isoforms are determined and the AFP-L3 ratio is accordingly calculated to favor the accurate HCC diagnosis. Experimental results prove the high-accuracy assay of AFP-L3 ratio based on the AFP quantitation in a linear range of 0.0008-40 ng mL^-1 and AFP-L3 quantitation in a linear range of 0.004-40 ng mL^-1. The aptasensor also displays satisfactory specificity and good recoveries even in the complex serum samples. Therefore, the aptasensor may provide a valuable tool for the assay of the AFP-L3 ratio and have a great potential use in early warning of HCC for clinical application.

Contrast-enhanced ultrasonography for the management of portal hypertension in cirrhosis

Portal hypertension is a major pathophysiological condition in patients with cirrhosis. This accounts for the occurrence and severity of the various manifestations. The degree is determined by the portal pressure or hepatic venous pressure gradients, both of which are obtained by invasive interventional radiological procedures. Ultrasound (US) is a simple and minimally invasive imaging modality for the diagnosis of liver diseases. Owing to the availability of microbubble-based contrast agents and the development of imaging modes corresponding to contrast effects, contrast-enhanced US (CEUS) has become popular worldwide for the detailed evaluation of hepatic hemodynamics, diffuse liver disease, and focal hepatic lesions. Recent advancements in digital technology have enabled contrast-based demonstrations with improved resolution, leading to a wider range of applications. This review article describes the current role, benefits, and limitations of CEUS in the management of portal hypertension.

Deep Learning Algorithms in the Automatic Segmentation of Liver Lesions in Ultrasound Investigations

BACKGROUND

The ultrasound is one of the most used medical imaging investigations worldwide. It is non-invasive and effective in assessing liver tumors or other types of parenchymal changes.

METHODS

The aim of the study was to build a deep learning model for image segmentation in ultrasound video investigations. The dataset used in the study was provided by the University of Medicine and Pharmacy Craiova, Romania and contained 50 video examinations from 49 patients. The mean age of the patients in the cohort was 69.57. Regarding presence of a subjacent liver disease, 36.73% had liver cirrhosis and 16.32% had chronic viral hepatitis (5 patients: chronic hepatitis C and 3 patients: chronic hepatitis B). Frames were extracted and cropped from each examination and an expert gastroenterologist labelled the lesions in each frame. After labelling, the labels were exported as binary images. A deep learning segmentation model (U-Net) was trained with focal Tversky loss as a loss function. Two models were obtained with two different sets of parameters for the loss function. The performance metrics observed were intersection over union and recall and precision.

RESULTS

Analyzing the intersection over union metric, the first segmentation model obtained performed better compared to the second model: 0.8392 (model 1) vs. 0.7990 (model 2). The inference time for both models was between 32.15 milliseconds and 77.59 milliseconds.

CONCLUSIONS

Two segmentation models were obtained in the study. The models performed similarly during training and validation. However, one model was trained to focus on hard-to-predict labels. The proposed segmentation models can represent a first step in automatically extracting time-intensity curves from CEUS examinations.

Contrast-enhanced ultrasound for the diagnosis of hepatocellular carcinoma in adults with chronic liver disease

BACKGROUND

Hepatocellular carcinoma occurs mostly in people with chronic liver disease. Worldwide, it ranks sixth in terms of incidence of cancer, and fourth in terms of cancer-related deaths. Contrast-enhanced ultrasound (CEUS) is used as an add-on test to confirm the presence of focal liver lesions suspected as hepatocellular carcinoma after prior diagnostic tests such as abdominal ultrasound or measurement of alpha-foetoprotein, or both. According to guidelines, a single contrast-enhanced imaging investigation, with either computed tomography (CT) or magnetic resonance imaging (MRI), may show the typical hepatocellular carcinoma hallmarks in people with cirrhosis, which will be sufficient to diagnose hepatocellular carcinoma. However, a significant number of hepatocellular carcinomas show atypical imaging features, and therefore, are missed at imaging. Dynamic CEUS images are obtained similarly to CT and MRI images. CEUS differentiates between arterial and portal venous phases, in which sonographic hepatocellular carcinoma hallmarks, such as arterial hyperenhancement and subsequent washout appearance, are investigated. The advantages of CEUS over CT and MRI include real-time imaging, use of contrast agents that do not contain iodine and are not nephrotoxic, and quick image acquisition. Despite the advantages, the use of CEUS in the diagnostic algorithm for HCC remains controversial, with disagreement on relevant guidelines. There is no clear evidence of the benefit of surveillance programmes in terms of overall survival as the conflicting results can be a consequence of an inaccurate detection, ineffective treatment, or both. Therefore, assessing the diagnostic accuracy of CEUS may clarify whether the absence of benefit could be related to underdiagnosis. Furthermore, an assessment of the accuracy of CEUS for the diagnosis of hepatocellular carcinoma is needed for either diagnosing hepatocellular carcinoma or ruling it out in people with chronic liver disease who are not included in surveillance programmes.

OBJECTIVES

1. To assess the diagnostic accuracy of contrast-enhanced ultrasound (CEUS) for the diagnosis of hepatocellular carcinoma of any size and at any stage in adults with chronic liver disease, in a surveillance programme or in a clinical setting. 2. To assess the diagnostic accuracy of CEUS for the diagnosis of resectable hepatocellular carcinoma in people with chronic liver disease and identify potential sources of heterogeneity in the results.

SEARCH METHODS

We used standard, extensive Cochrane search methods. The last date of search was 5 November 2021.

SELECTION CRITERIA

We included studies assessing the diagnostic accuracy of CEUS for the diagnosis of hepatocellular carcinoma in adults with chronic liver disease, with cross-sectional designs, using one of the acceptable reference standards, such as pathology of the explanted liver, and histology of resected or biopsied focal liver lesion with at least a six-month follow-up.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methods to screen studies, extract data, and assess the risk of bias and applicability concerns, using the QUADAS-2 checklist. We used the bivariate model and provided estimates of summary sensitivity and specificity. We assessed the certainty of the evidence using GRADE. We presented uncertainty-of-the-accuracy estimates using 95% confidence intervals (CIs).

MAIN RESULTS

We included 23 studies with 6546 participants. Studies were published between 2001 and 2021. We judged all 23 studies at high-risk of bias in at least one domain, and 13/23 studies at high concern for applicability. Most studies used different reference standards to exclude the presence of the target condition. The time interval between the index test and the reference standard was rarely defined. We also had major concerns on their applicability due to the characteristics of the participants. - CEUS for hepatocellular carcinoma of any size and stage: sensitivity 77.8% (95% CI 69.4% to 84.4%) and specificity 93.8% (95% CI 89.1% to 96.6%) (23 studies, 6546 participants; very low-certainty evidence). - CEUS for resectable hepatocellular carcinoma: sensitivity 77.5% (95% CI 62.9% to 87.6%) and specificity 92.7% (95% CI 86.8% to 96.1%) (13 studies, 1257 participants; low-certainty evidence). The observed heterogeneity in the results remains unexplained. The sensitivity analyses, including only studies with clearly prespecified positivity criteria and only studies in which the reference standard results were interpreted with no knowledge of the results about the index test, showed no differences in the results.

AUTHORS' CONCLUSIONS

We found that by using CEUS, as an add-on test following abdominal ultrasound, to diagnose hepatocellular carcinoma of any size and stage, 22% of people with hepatocellular carcinoma would be missed, and 6% of people without hepatocellular carcinoma would unnecessarily undergo further testing or inappropriate treatment. As to resectable hepatocellular carcinoma, we found that 23% of people with resectable hepatocellular carcinoma would incorrectly be unresected, while 8% of people without hepatocellular carcinoma would undergo further inappropriate testing or treatment. The uncertainty resulting from the high risk of bias of the included studies, heterogeneity, and imprecision of the results and concerns on their applicability limit our ability to draw confident conclusions.

The diagnostic performance of contrast-enhanced CT versus extracellular contrast agent-enhanced MRI in detecting hepatocellular carcinoma: direct comparison and a meta-analysis

To compare the diagnostic value of contrast-enhanced computed tomography (CT) with extracellular contrast agent-enhanced magnetic resonance imaging (ECA-MRI) for the detection of hepatocellular carcinoma (HCC). Pubmed, Embase, Web of Science and Cochrane Library were searched (1/5/2021) for studies comparing contrast-enhanced CT with ECA-MRI in patients suspected of HCC. Studies without head-to-head comparison were excluded. The pooled sensitivity, specificity and summary area under the curve (sAUC) of contrast-enhanced CT and ECA-MRI in detecting HCC was calculated based on bivariate random effects model. Heterogeneity test included threshold effect analysis and meta-regression. Subgroup analyses were conducted according to lesion size (< 20 mm or ≥ 20 mm). Overall, 10 articles containing 1333 patients were deemed suitable for inclusion in this meta-analysis. ECA-MRI displayed increased sensitivity to contrast-enhanced CT in detecting HCC (0.77 vs. 0.63, P < 0.01). The difference in specificity between ECA-MRI and contrast-enhanced CT was not statistically significant (0.93 vs. 0.94, P = 0.25). ECA-MRI yielded higher diagnostic accuracy (sAUCs = 0.88 vs. 0.80, P < 0.01). In the subgroup analysis with a lesion size < 20 mm, ECA-MRI allowed significant gains of accuracy compared to contrast-enhanced CT (0.79 vs. 0.72, P = 0.02). ECA-MRI also outperformed contrast-enhanced CT in patients with lesion size ≥ 20 mm (sAUCs = 0.96 vs. 0.93, P = 0.04). ECA-MRI provided higher sensitivity and accuracy than contrast-enhanced CT in detecting HCC, especially lesions size < 20 mm.

The Diagnostic Value of Contrast-Enhanced Ultrasound and Enhanced CT Combined with Tumor Markers AFP and CA199 in Liver Cancer

Background

Early screening and diagnosis are of great significance to the treatment and prognosis of patients with liver cancer. This study aims to explore the application value of contrast-enhanced ultrasound and enhanced CT combined with tumor markers alpha-fetoprotein (AFP) and carbohydrate antigen 199 (CA199) in the diagnosis of liver cancer.

Methods

Liver cancer group (n = 256), benign disease group (n = 110), and control group (n = 50) participated in this study. The liver cancer and benign disease groups were diagnosed pathologically by contrast-enhanced ultrasound and enhanced CT before operation. The electrochemiluminescence method was used to detect the content of AFP and CA199. And the receiver operating characteristic (ROC) curve was drawn.

Results

The detection rate of contrast-enhanced ultrasound is higher than that of enhanced CT. Serum levels of AFP and CA199 in the liver cancer group were significantly higher than those in the benign lesion group and the control group. The ROC curve showed that the sensitivity, accuracy, and negative prediction rate of contrast-enhanced ultrasound and enhanced CT combined with tumor markers AFP and CA199 in the diagnosis of liver cancer were significantly higher than that of a single test.

Conclusion

The combined detection of contrast-enhanced ultrasound and enhanced CT, AFP, and CA199 significantly improved the sensitivity and accuracy of liver cancer diagnosis. It has a significant effect on the early diagnosis of liver cancer and can be used as an important means of early screening.

Surveillance for hepatocellular carcinoma at the community level: Easier said than done

Surveillance for hepatocellular carcinoma (HCC) in high-risk patients with semiannual ultrasound examinations is advocated by all international guidelines. However, as long as the identification of the population to be screened and the surveillance programs are not well implemented, the real-life impact of HCC surveillance in reducing mortality for HCC cannot be known. We propose a new approach that promotes the identification of cirrhotic patients by primary care physicians (PCPs) and referral of patients to the hepatologist for surveillance. Surveillance should be incorporated, when feasible, in a hub and spoke model of comprehensive hepatology care. Training PCPs to identify cirrhotic patients and performing surveillance in a subspecialist setting are equally important to improve the effectiveness of real-life surveillance and to decrease HCC mortality over time.

The semi-erect position for better visualization of subphrenic hepatocellular carcinoma during ultrasonography examinations

PURPOSE

This study investigated which body position is more useful for visualizing subphrenic hepatocellular carcinomas (HCCs) during ultrasonography (US) examinations.

METHODS

This prospective study was approved by the institutional review board and written informed consent was obtained from all patients. Twenty consecutive patients with a single subphrenic HCC (treatment-naïve, 1 to 3 cm) underwent a US examination for planning radiofrequency ablation. The examinations were done by one of three radiologists and the patients were examined in four different body positions-supine, right posterior oblique (RPO), left lateral decubitus (LLD), and semi-erect-by being positioned on a tilted table. The visibility of the index tumor was prospectively assessed using a 4-point scale. Needle insertion was considered to be technically feasible if the visibility score was lower than 2. The visibility score and technical feasibility were compared using the Wilcoxon signed rank test and the McNemar test, respectively, for pairwise comparisons between different body positions.

RESULTS

The visibility score was significantly lower in the semi-erect position (median, 2; interquartile range, 1 to 2.75) than in the supine (3, 2 to 4), RPO (3, 2 to 4), and LLD (4, 3.25 to 4) positions (P=0.007, P=0.005, and P=0.001, respectively). The technical feasibility of needle insertion was also significantly higher in the semi-erect position (75%, 15/20) than in the supine (45%, 9/45), RPO (35%, 7/20), and LLD (20%, 4/20) positions (P=0.031, P=0.021, and P=0.001, respectively).

CONCLUSION

The semi-erect position is more useful for the visualization of subphrenic HCCs than the supine, RPO, or LLD positions.

A Concise Review on the Frequency, Major Risk Factors and Surveillance of Hepatocellular Carcinoma (HCC) in β-Thalassemias: Past, Present and Future Perspectives and the ICET-A Experience

Due to the recent alarming increase in the incidence of hepatocellular carcinoma (HCC) in thalassemias, the present report reviews briefly the frequency, the major risk factors, and the surveillance of HCC in β-thalassemias. Over the past 33 years, 153 cases of HCC were reported in patients with thalassemia, mainly in Italy and Greece. Among HCV-infected patients, additional factors promoting the development of HCC included: advanced age, male sex, chronic hepatitis B (CHB) co-infection, and iron overload. For early diagnosis of HCC, sequential ultrasound screening is recommended especially for thalassemia patients with chronic hepatitis C (CHC), which coincides with (one or more) additional risk factors for HCC. Here we report also the preliminary data from thalassemic patients, above the age of 30 years, followed in 13 ICET-A centers. The total number of enrolled patients was 1,327 (males: 624 and 703 females). The prevalence of HCC in thalassemia major patients [characterized by transfusion-dependency (TDT)] and thalassemia intermedia [characterized by nontransfusion dependency (NTDT)] was 1.66 % and 1.96 %, respectively. The lowest age at diagnosis of HCC was 36 years for TDT and 47 years for NTDT patients. We hope that this review can be used to develop more refined and prospective analyses of HCC magnitude and risk in patients with thalassemia and to define specific international guidelines to support clinicians for early diagnosis and treatment of HCC in thalassemic patients.

A Nude Mouse Model of Orthotopic Liver Transplantation of Human Hepatocellular Carcinoma HCCLM3 Cell Xenografts and the Use of Imaging to Evaluate Tumor Progression

Background

This study aimed to develop a nude mouse model of orthotopic liver transplantation of HCCLM3 human hepatocellular carcinoma (HCC) cell xenografts and the use of imaging and histology to evaluate tumor development and progression.

Material/Methods

HCCLM3 cells were injected subcutaneously into 25 healthy male athymic BALB/c (nu/nu) nude mice. The tumors that developed were transplanted into the liver of a new set of nude mice. After four weeks and six weeks, the mice were imaged using ultrasound (US), software-assisted contrast-enhanced ultrasound (CEUS), fluorodeoxyglucose-positron emission tomography (FDG-PET). Histology was performed on the liver and liver tumors, and included immunohistochemistry for vascular endothelial growth factor (VEGF), CD31, CD34, and α-smooth muscle actin (α-SMA).

Results

The success rate for orthotopic tumor transplantation in the mouse liver was 90% (18/20). Liver tumors measured 11.8±2.6 mm in diameter and 525.9±250.8 mm3 in volume on the sixth week. CEUS showed rapid wash-in and washout in the liver tumors, and PET showed low tumor cell metabolism. Bone metastases were present in 45% (9/20) of mice in the sixth week. Immunohistochemistry showed positive expression for VEGF, CD31, CD34, and α-SMA.

Conclusions

The nude mouse orthotopic liver transplantation model of human HCC was shown to be a reliable model that has the potential for future research on the pathogenesis and progression of HCC and studies on drug development.

[Contrast-enhanced ultrasound in differential diagnosis of focal liver lesions]

AIM

To continue studying the features of visualization of focal liver lesions by using of contrast-enhanced ultrasound (CEUS).

MATERIAL AND METHODS

A retrospective analysis included 106 patients with morphologically confirmed benign liver tumors and metastases (MTS). Patients were divided into groups regarding morphological criteria: focal-nodular hyperplasia (FNH) - 22 patients, hemangiomas - 26, hepatocellular adenoma (HCA) - 15 and 43 patients with liver MTS. All patients underwent multiparametric ultrasound examination with CEUS.

RESULTS

Characteristic signs of FNH are early contrasting in the arterial phase (AF) and significantly different 'contrasting onset in focus' in comparison with hemangiomas (p<0.001), HCA and MTS (p<0.05). Specific signs: 'spokes of the wheel' symptom and advanced contrast accumulation (96%), 'center-to-edge' filling (86%). There was no contrasting in AF in 42% of patients with hemangiomas. Specific signs are 'peripheral nodular exacerbation' (92%) and 'edge-to-center' filling (76%). WASH-OUT sign is not typical. HCA is characterized by complete (100%) and intensive (80%) centripetal filling. WASH-OUT sing was detected in 6 (40%) patients (p<0.001 for 'wash-out onset' and p<0.005 for 'maximum wash-out time' in comparison with MTS). We did not find specific types of vascular pattern. The most important differential sign of MTS was WASH-OUT sign (100%). Me of 'wash-out onset' sign was 40 (35-56) seconds. Specific signs: 'black hole' symptom - 50% of patients, asymmetric vascular pattern - 39.5%, circumferential exacerbation (27.9%) and hypoperfusion zones in AF (32.6%).

Contrast-enhanced US with Perfluorobutane for Hepatocellular Carcinoma Surveillance: A Multicenter Diagnostic Trial (SCAN)

Background US has served as a standard surveillance tool for hepatocellular carcinoma (HCC); however, the detection rate and false referral rate with this modality are suboptimal. Purpose To evaluate the added value of perfluorobutane-enhanced US when combined with conventional B-mode US as an HCC surveillance tool in participants with liver cirrhosis. Materials and Methods This prospective multi-institution diagnostic trial (https://ClinicalTrials.gov, NCT02188901) used an intraindividual comparison design in a single arm of study participants and was conducted at five referral hospitals. Eligible participants who had liver cirrhosis related to viral hepatitis and were undergoing US for HCC surveillance were enrolled from October 2014 to August 2016. Immediately after completion of B-mode US but before performance of perfluorobutane-enhanced US, operating radiologists entered the results of B-mode US. After completion of subsequent perfluorobutane-enhanced US (Kupffer phase with or without vascular-phase US), the radiologists recorded the results. The presence of HCC was confirmed either with pathologic analysis or radiologically by using dynamic contrast material-enhanced CT or gadoxetic acid-enhanced MRI. The primary end points were the detection rate of early-stage HCC (Barcelona Clinic Liver Cancer staging system stage 0 or A) and false referral rate. The primary end points were compared in a per-participant manner by using the McNemar test. Results A total of 524 participants (mean age, 54 years ± 9 [standard deviation]) were included. Of these, 493 (94.1%) had liver cirrhosis related to the hepatitis B virus. Ten HCCs were confirmed in eight participants. The detection rate of early-stage HCC was not significantly improved by adding perfluorobutane-enhanced US to conventional B-mode US (difference, 0.4% [95% confidence interval: -0.3%, 1.1%]; P = .16). The false referral rate was significantly reduced (difference, -3.2% [95% confidence interval: -5.0%, -1.4%]; P < .001). Conclusion The addition of perfluorobutane-enhanced US to conventional B-mode US reduced the false referral rate without a significant improvement in the detection rate of early-stage hepatocellular carcinoma for surveillance in a population in which the hepatitis B virus predominated. © RSNA, 2019 Online supplemental material is available for this article.

Contrast-enhanced ultrasound in the diagnosis of endometrial carcinoma: A meta-analysis

The present study evaluated the diagnostic value of contrast-enhanced ultrasound (CEUS) in endometrial carcinoma (EC). Articles published until 31 January 2017 were retrieved from PubMed, EMBASE, Elsevier, Springer and Google scholar, with the following inclusion criteria: i) The accuracy (sensitivity and specificity) of CEUS in the diagnosis of EC was evaluated; ii) a gold standard was adopted to treat and confirm EC, including surgery, histopathology and appropriate follow-up (as included in the meta-analysis); iii) the data allowed for construction of a 2×2 table of positives, false-positives, negatives and false-negatives. Pooled estimates of sensitivity, specificity, risk ratios and diagnostic odds ratios (DOR) were calculated in the present meta-analysis of the accuracy of CEUS in diagnosing EC. The summary receiver-operating characteristics (sROC) curve was also constructed. Among the 93 relevant articles, 7 studies were finally selected according to the inclusion criteria with a sample size of n=275. The pooled sensitivity of CEUS in the diagnosis of EC was 84% [95% confidence interval (CI), 0.78-0.88], while the pooled specificity was 90% (95% CI, 0.86-0.92). The positive likelihood ratio (+LR) of CEUS was 8.0 (95% CI, 5.9-10.8) and the negative likelihood ratio (-LR) was 0.18 (95% CI, 0.13-0.25). The DOR was 44 (95% CI, 26-77). The area under the sROC curve was 0.93 with specificity of 0.90 (0.86-0.92) and sensitivity of 0.84 (0.78-0.88) for the summary operating point. Moderate heterogeneity was observed for sensitivity, specificity and DOR with I² values of 32.56, 34.68 and 41.2%, respectively. No significant publication bias was observed for the DOR of CEUS. In conclusion, the present meta-analysis indicates that CEUS is valuable in the diagnosis of EC. Additional clinical data and studies are still required to confirm these results and to further develop the diagnostic application of CEUS in EC.

Contrast-enhanced US for characterization of focal liver lesions: a comprehensive meta-analysis

OBJECTIVES

This meta-analysis was performed to evaluate the accuracy of contrast-enhanced ultrasound (CEUS) in differentiating malignant from benign focal liver lesions (FLLs).

METHODS

Cochrane Library, PubMed and Web of Science databases were systematically searched and checked for studies using CEUS in characterization of FLLs. Data necessary to construct 2×2 contingency tables were extracted from included studies. The QUADAS tool was utilized to assess the methodologic quality of the studies. Meta-analysis included data pooling, subgroup analyses, meta-regression and investigation of publication bias was comprehensively performed.

RESULTS

Fifty-seven studies were included in this meta-analysis and the overall diagnostic accuracy in characterization of FLLs was as follows: pooled sensitivity, 0.92 (95%CI: 0.91-0.93); pooled specificity, 0.87 (95%CI: 0.86-0.88); diagnostic odds ratio, 104.20 (95%CI: 70.42-154.16). Subgroup analysis indicated higher diagnostic accuracy of the second-generation contrast agents (CAs) than the first-generation CA (Levovist; DOR: 118.27 vs. 62.78). Furthermore, Sonazoid demonstrated the highest diagnostic accuracy among three major CAs (SonoVue, Levovist and Sonazoid; DOR: 118.82 vs. 62.78 vs. 227.39). No potential publication bias was observed of the included studies.

CONCLUSION

CEUS is an accurate tool to stratify the risk of malignancy in FLLs. The second-generation CAs, especially Sonazoid may greatly improve diagnostic performance.

KEY POINTS

• CEUS shows excellent diagnostic accuracy in differentiating malignant from benign FLLs. • The second-generation CAs have higher diagnostic accuracy than first-generation CAs. • Sonazoid demonstrates the highest diagnostic accuracy among three major CAs.

Radiologically Undetected Hepatocellular Carcinoma in Patients Undergoing Liver Transplantation: An Immunohistochemical Correlation With LI-RADS Score

Orthotopic liver transplantation is the best option for patients with carefully selected unresectable disease because of underlying liver dysfunction. The 5-year survival rate after orthotopic liver transplantation for early detected hepatocellular carcinoma (HCC) is high, and a similar or even higher rate is reported in those with radiologically undetected HCC. This study evaluated and compared the histologic features of pretransplant radiologically undetected (14 patients, 25 tumors) versus detected (36 patients, 45 tumors) HCCs. Tumor size, tumor differentiation, number of unpaired arteries, mitotic count per 10 high-power fields, CD34 immunostain to assess microvessel density, and Ki67 immunostain were compared with the Liver Imaging Reporting and Data System score, which was retrospectively assigned to each tumor in both groups. The Liver Imaging Reporting and Data System score was significantly higher in the HCC detected group (P<0.001). The vast majority of the undetected HCCs (88%) was <2 cm in size. Only 12% of the undetected HCCs were ≥2 cm, whereas 51% of the detected HCCs were ≥2 cm in size. Higher rate of moderate to poor tumor differentiation was noted in the detected HCCs compared with the undetected group (89% vs. 60%; P=0.004). No statistically significant difference in the number and distribution of unpaired arteries, or mitotic count was observed in 2 groups (although fewer unpaired arteries were identified in the undetected group). The detected HCCs had a higher rate of 2+ CD34 staining compared with the undetected HCCs (68% vs. 27%; P=0.002), whereas the opposite was observed for 1+ CD34 staining (59% undetected HCCs vs. 17% detected HCCs; P=0.002). Ki67 proliferative index was not statistically different between the 2 groups (120.8/1000 cells detected HCCs vs. 81.8/1000 cells undetected HCCs; P=0.36). The factors associated with failing to detect HCCs pretransplant by radiologic studies include small tumor size (<2 cm), low-grade histologic differentiation, and low microvessel density (low CD34 staining). A significant association between the number and distribution of unpaired arteries and HCC detection has not been established by our study.

Histology-Based Assessment of Sonazoid-Enhanced Ultrasonography for the Diagnosis of Liver Metastasis

This retrospective study aimed to assess the diagnostic performance of contrast-enhanced ultrasound with Sonazoid (S-CEUS) for liver metastasis. We enrolled in this study 98 patients with 148 histologically proven liver lesions, with 121 metastases and 27 non-metastases. The S-CEUS technique showed sensitivity in 95.0% (115 of 121), specificity in 44.4% (12 of 27) and accuracy in 85.8% (127 of 148) for the diagnosis of metastasis. Higher body mass index had a negative influence on the positive predictive value and accuracy, and a greater depth of the lesion had a negative influence on the accuracy. The management was changed in 8 patients (8.2%) because of S-CEUS findings. In conclusion, the addition of S-CEUS may offer a great benefit by improvement of the quality of diagnosis and management for patients with cancer who have a tentative diagnosis of liver metastasis by contrast-enhanced computed tomography.

From diagnosis to treatment of hepatocellular carcinoma: An epidemic problem for both developed and developing world

Hepatocellular carcinoma (HCC) is the most frequent primary liver malignancy and the third cause of cancer-related death in the Western Countries. The well-established causes of HCC are chronic liver infections such as hepatitis B virus or chronic hepatitis C virus, nonalcoholic fatty liver disease, consumption of aflatoxins and tobacco smocking. Clinical presentation varies widely; patients can be asymptomatic while symptomatology extends from right upper abdominal quadrant paint and weight loss to obstructive jaundice and lethargy. Imaging is the first key and one of the most important aspects at all stages of diagnosis, therapy and follow-up of patients with HCC. The Barcelona Clinic Liver Cancer Staging System remains the most widely classification system used for HCC management guidelines. Up until now, HCC remains a challenge to early diagnose, and treat effectively; treating management is focused on hepatic resection, orthotopic liver transplantation, ablative therapies, chemoembolization and systemic therapies with cytotocix drugs, and targeted agents. This review article describes the current evidence on epidemiology, symptomatology, diagnosis and treatment of hepatocellular carcinoma.

Assessing diagnostic value of contrast-enhanced ultrasound and contrast-enhanced computed tomography in detecting small hepatocellular carcinoma: A meta-analysis

BACKGROUND

This study aimed to compare the diagnostic values of contrast-enhanced ultrasound (CEUS) and contrast-enhanced computed tomography (CECT) in detecting small hepatocellular carcinoma (SHCC).

METHODS

A series of related articles from 2001 to 2015 were searched in PubMed and Embase databases. Data from selected articles were pooled to analyze the sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), diagnostic odds ratio (DOR), and summary receiver operating characteristic (SROC) curve using Meta-DiSc software. Heterogeneity was estimated using χ-based Cochran-Q test and I-statistics, and publication bias was estimated using Egger test in Stata software.

RESULTS

In total, 8 high-quality articles based on 623 subjects including 318 SHCC cases were included. For the extracted data, no heterogeneity and publication bias were observed among these studies. The following respective data on CEUS and CECT were pooled: sensitivities: 0.75 (95% confidence interval [CI]: 0.70-0.80) and 0.74 (95% CI: 0.68-0.78); specificity: 0.91 (95% CI: 0.87-0.94) and 0.92 (95% CI: 0.89-0.95); PLRs: 5.99 (95%CI: 3.28-10.92) and 7.76 (95% CI: 3.12-19.28); NLRs: 0.31 (95% CI: 0.20-0.49) and 0.32 (95% CI: 0.20-0.50); DORs: 27.38 (95% CI: 14.38-52.11) and 30.02 (95% CI: 9.32-96.62). Area under the SROC curve: 0.91 and 0.89 and no significant statistical result was identified between them (Z = 0.23, P = .82).

CONCLUSION

CEUS showed a diagnostic ability comparable to that of CECT in detecting SHCC.

A five-miRNA expression signature predicts survival in hepatocellular carcinoma

The aim of this study was to identify a microRNA (miRNA) expression signature for predicting HCC (hepatocellular carcinoma) survival. A total of 322 HCC patients in The Cancer Genome Atlas (TCGA) database were randomly divided into training and testing set. miRNAs, associated with survival time in the training set, were identified by using univariate Cox regression analysis. The risk score was formulated based on the expression levels of these miRNAs. Then the miRNA signature was validated in testing set through Kaplan-Meier analysis and log-rank test. hsa-miR-301a, hsa-miR-132, hsa-miR-212, hsa-miR-489, and hsa-miR-1468 were identified to formulate risk score in training set and used to calculate the risk score of each patients in testing set. About 161 patients in testing set were segregated into high- and low-risk group according to the median risk score. The survival time of high-risk group was significantly shorter (p = 0.0248) than low-risk group in testing test. The target genes of five miRNAs were significantly enriched in valine, leucine, and isoleucine degradation pathway and PPAR signaling pathway. hsa-miR-1468 had an up-regulated tendency in HCC tissues compared to adjacent tumor tissues. The expression of hsa-miR-301a, hsa-miR-132, hsa-miR-212, hsa-miR-489, and hsa-miR-1468, which might be potential biomarkers to evaluate HCC patients' prognosis.

Non-invasive assessment of portal hypertension and liver fibrosis using contrast-enhanced ultrasonography

Portal hypertension and hepatic fibrosis are key pathophysiologies with major manifestations in cirrhosis. Although the degree of portal pressure and hepatic fibrosis are pivotal parameters, both are determined using invasive procedures. Ultrasound (US) is a simple and non-invasive technique that is available for use worldwide in the abdominal field. Because of its safety and easy of use, contrast-enhanced US is one of the most frequently used tools in the management of liver tumors for the detection and characterization of lesions, assessment of malignancy grade, and evaluation of therapeutic effects. This wide range of applications drives the practical use of contrast-enhanced US for evaluation of the severity of portal hypertension and hepatic fibrosis. The present article reviews the recent progress in contrast-enhanced US for the assessment of portal hypertension and hepatic fibrosis.

Intensity-Based Assessment of Microbubble-Enhanced Ultrasonography: Phase-Related Diagnostic Ability for Cellular Differentiation of Hepatocellular Carcinoma

This prospective study aimed to elucidate the effect of phase-related quantitative parameters of contrast-enhanced ultrasound (CEUS) with perflubutane microbubble agent to assess the cellular differentiation of hepatocellular carcinoma (HCC). Intensity was analyzed in 94 lesions (19.4 ± 4.9 mm, 86 patients), 47 well-differentiated HCCs (wHCCs) and 47 moderately-differentiated HCCs (mHCCs): I(e) (early phase) = I(te) (tumor) - I(le) (liver), I(p) (post-vascular phase) = I(tp) (tumor) - I(lp) (liver), I(ep) = I(e) - I(p). The area under the receiver operating characteristic curve with the best cutoff value (I(e), 13.2, I(p), -4.5, I(ep), 21.3) for discriminating between wHCC and mHCC was 0.6922 for Ie, 0.7680 for Ip and 0.7925 for Iep, which indicated a significantly greater ability to differentiate between wHCC and mHCC compared with visual/qualitative assessment (early phase, 0.6170, p = 0.04; post-vascular phase, 0.6702, p = 0.01; both phases, 0.7021, p = 0.04). In conclusion, I(ep) was found to have the highest diagnostic ability, suggesting it is a promising parameter for the cellular differentiation of HCCs with CEUS.

Diagnosing Borderline Hepatic Nodules in Hepatocarcinogenesis: Imaging Performance

OBJECTIVE

The purposes of this article are to describe the pathologic and radiologic features of small nodular lesions and to offer insight into the multistep process of hepatocarcinogenesis by describing the progression of imaging changes that link dysplastic nodules and early hepatocellular carcinoma, (HCC) to small HCC that has progressed.

CONCLUSION

Nodules larger than 1 cm found during ultrasound surveillance of a cirrhotic liver should be investigated further with diagnostic imaging. Contrast-enhanced CT and dynamic MRI are the primary diagnostic studies for the diagnosis of HCC; contrast-enhanced ultrasound can be used as an alternative test. If a nodule has the typical hallmark of hypervascularity in the hepatic arterial phase with washout in the portal venous or delayed phase, a definitive diagnosis of HCC can be made. Nodules found during ultrasound surveillance that are smaller than 1 cm can be followed with ultrasound examinations at intervals of 3-6 months.

Predictive factors of contrast-enhanced ultrasonography for the response to transarterial chemoembolization in hepatocellular carcinoma

Background/Aims

The predictive role of contrast-enhanced ultrasonography (CEUS) before performing transarterial chemoembolization (TACE) has not been determined. We assessed the possible predictive factors of CEUS for the response to TACE.

Methods

Seventeen patients with 18 hepatocellular carcinoma (HCC) underwent TACE. All of the tumors were studied with CEUS before TACE using a second-generation ultrasound contrast agent (SonoVue®, Bracco, Milan, Italy). The tumor response to TACE was classified with a score between 1 and 4 according to the remaining enhancing-tumor percentage based on modified response evaluation criteria in solid tumors (mRECIST): 1, enhancing tumor <25%; 2, 25%≤enhancing tumor<50%; 3, 50%≤enhancing tumor<75%; and 4, enhancing tumor≥75%). A score of 1 was defined as a "good response" to TACE. The predictive factors for the response to TACE were evaluated during CEUS based on the maximum tumor diameter, initial arterial enhancing time, arterial enhancing duration, intensity of arterial enhancement, presence of a hypoenhanced pattern, and the feeding artery to the tumor.

Results

The median tumor size was 3.1 cm. The distribution of tumor response scores after TACE in all tumors was as follows: 1, n=11; 2, n=4; 3, n=2; and 4, n=1. Fifteen tumors showed feeding arteries. The presence of a feeding artery and the tumor size (≤5 cm) were the predictive factors for a good response (P=0.043 and P=0.047, respectively).

Conclusions

The presence of a feeding artery and a tumor size of less than 5 cm were the predictive factors for a good response of HCC to TACE on CEUS.

Imaging Techniques for the Diagnosis of Hepatocellular Carcinoma: A Systematic Review and Meta-analysis

BACKGROUND

Several imaging modalities are available for diagnosis of hepatocellular carcinoma (HCC).

PURPOSE

To evaluate the test performance of imaging modalities for HCC.

DATA SOURCES

MEDLINE (1998 to December 2014), the Cochrane Library Database, Scopus, and reference lists.

STUDY SELECTION

Studies on test performance of ultrasonography, computed tomography (CT), or magnetic resonance imaging (MRI).

DATA EXTRACTION

One investigator abstracted data, and a second investigator confirmed them; 2 investigators independently assessed study quality and strength of evidence.

DATA SYNTHESIS

Few studies have evaluated imaging for HCC in surveillance settings. In nonsurveillance settings, sensitivity for detection of HCC lesions was lower for ultrasonography without contrast than for CT or MRI (pooled difference based on direct comparisons, 0.11 to 0.22), and MRI was associated with higher sensitivity than CT (pooled difference, 0.09 [95% CI, 0.07 to 12]). For evaluation of focal liver lesions, there were no clear differences in sensitivity among ultrasonography with contrast, CT, and MRI. Specificity was generally 0.85 or higher across imaging modalities, but this item was not reported in many studies. Factors associated with lower sensitivity included use of an explanted liver reference standard, and smaller or more well-differentiated HCC lesions. For MRI, sensitivity was slightly higher for hepatic-specific than nonspecific contrast agents.

LIMITATIONS

Only English-language articles were included, there was statistical heterogeneity in pooled analyses, and costs were not assessed. Most studies were conducted in Asia and had methodological limitations.

CONCLUSION

CT and MRI are associated with higher sensitivity than ultrasonography without contrast for detection of HCC; sensitivity was higher for MRI than CT. For evaluation of focal liver lesions, the sensitivities of ultrasonography with contrast, CT, and MRI for HCC are similar.

PRIMARY FUNDING SOURCE

Agency for Healthcare Research and Quality. (

PROSPERO

CRD42014007016).

CT and MR imaging diagnosis and staging of hepatocellular carcinoma: part II. Extracellular agents, hepatobiliary agents, and ancillary imaging features

Computed tomography (CT) and magnetic resonance (MR) imaging play critical roles in the diagnosis and staging of hepatocellular carcinoma (HCC). The second article of this two-part review discusses basic concepts of diagnosis and staging, reviews the diagnostic performance of CT and MR imaging with extracellular contrast agents and of MR imaging with hepatobiliary contrast agents, and examines in depth the major and ancillary imaging features used in the diagnosis and characterization of HCC.

Rare benign tumors of the liver: still rare?

Background

Benign liver tumors are common. They do not spread to other areas of the body, and they usually do not pose a serious health risk. In fact, in most cases, benign liver tumors are not diagnosed because patients are asymptomatic. When they are detected, it’s usually because the person has had medical imaging tests, such as an ultrasound (US), computed tomography (CT) scan, or magnetic resonance imaging (MRI), for another condition.

Materials and methods

A search of the literature was made using cancer literature and the PubMed, Scopus, and Web of Science (WOS) database for the following keywords: “hepatic benign tumors”, “hepatic cystic tumors”, “polycystic liver disease”, “liver macroregenerative nodules”, “hepatic mesenchymal hamartoma”, “hepatic angiomyolipoma”, “biliary cystadenoma”, and “nodular regenerative hyperplasia”.

Discussion and conclusion

Hepatocellular carcinoma (HCC) is one of the most common malignant tumors in some areas of the world; there is an increasing incidence worldwide. Approximately 750,000 new cases are reported per year. More than 75 % of cases occur in the Asia-Pacific region, largely in association with chronic hepatitis B virus (HBV) infection. The incidence of HCC is increasing in the USA and Europe because of the increased incidence of hepatitis C virus (HCV) infection. Unlike the liver HCC, benign tumors are less frequent. However, they represent a chapter always more interesting of liver disease. In fact, a careful differential diagnosis with the forms of malignant tumor is often required in such a way so as to direct the patient to the correct therapy. In conclusion, many of these tumors present with typical features in various imaging studies. On occasions, biopsies are required, and/or surgical removal is needed. In the majority of cases of benign hepatic tumors, no treatment is indicated. The main indication for treatment is the presence of significant clinical symptoms or suspicion of malignancy or fear of malignant transformation.

Lack of arterial hypervascularity at contrast-enhanced ultrasound should not define the priority for diagnostic work-up of nodules <2 cm

BACKGROUND & AIMS

Current guidelines recommend diagnostic work-up for nodules >1cm detected during screening for hepatocellular carcinoma (HCC). This implies that patients with benign conditions may undergo unnecessary evaluation and those with small nodules may be intervened too early, leading to overdiagnosis. Since increased arterial vascularization is the hallmark of malignancy, its detection by contrast-enhanced ultrasound (CEUS) could become the signal to proceed with diagnosis confirmation. The aim was to assess if HCCs <2 cm without arterial hyperenhancement by baseline CEUS have a benign evolutionary profile, suggesting that diagnosis and invasive treatment could be delayed until detection of an overt malignant profile, associated with increased vascularization.

METHODS

We prospectively included 168 cirrhotic patients with a newly detected solitary nodule of 5-20mm by screening ultrasonography. MRI, CEUS and fine needle biopsy (FNB) were performed and if no confident diagnosis was obtained, patients were closely followed to rule out HCC. Final diagnosis was: HCC (n = 119), cholangiocarcinoma (n = 3), neuroendocrine tumour (n = 1) and benign lesions (n = 45).

RESULTS

CEUS did not detect contrast hyperenhancement in the arterial phase in 55 cases (34%). Eighteen out of these 55 nodules were diagnosed as HCC. Non-CEUS hyperenhanced HCCs were more frequently well-differentiated than CEUS-hyperenhanced HCCs (p < 0.004). Fourteen patients were treated with ablation and 4 with resection. Ten (55.6%) patients experienced tumour recurrence after treatment, mostly distant, confirming their overt malignant profile.

CONCLUSIONS

Absence of contrast hyperenhancement on CEUS during the arterial phase in nodules <2 cm in a cirrhotic liver does not predict a less malignant profile. Accordingly, priority for diagnostic work-up and treatment should not differ according to contrast profiles on CEUS.

Serum gp73 is also a biomarker for diagnosing cirrhosis in population with chronic HBV infection

OBJECTIVES

To clarify the role of Golgi membrane glycoprotein 73 (gp73) in evaluating the progression of chronic hepatitis B virus (HBV) infection.

DESIGN AND METHODS

Participants included 958 controls, 421 chronic hepatitis B, 944 hepatic cirrhosis, and 127 hepatocellular carcinoma (HCC) patients. All the patients, with the exception of the controls, were diagnosed HBsAg positive. Serum biomarkers, including gp73, alpha-fetoprotein (AFP), alpha-l-fucosidase, and Lens culinaris agglutinin-reactive fraction of AFP, were determined.

RESULTS

The patients with Hepatic cirrhosis gp73 levels over 150 ng/mL had an odds ratio of 3.21 (95% CI: 2.07-5.00). In hepatic cirrhosis patients, serum gp73 correlated with the Child-Pugh score. gp73 is a marker for diagnosing cirrhosis in the hepatitis populations. When the cut-off was set at 75.5 ng/mL, the sensitivity, specificity, and AUC were 75.6% (95% CI: 71.30%-79.62%), 60.3% (95% CI: 56.95%-63.63%) and 0.72 (95% CI: 0.69-0.75), respectively.

CONCLUSION

The variation trend of gp73 in chronic liver disease may indicate that monitoring of serum gp73 is helpful to diagnose cirrhosis in population with chronic HBV infection.

Factors that affect efficacy of ultrasound surveillance for early stage hepatocellular carcinoma in patients with cirrhosis

BACKGROUND & AIMS

Ultrasound surveillance does not detect early stage hepatocellular carcinomas (HCCs) in some patients with cirrhosis, although the reasons for this have not been well studied. We assessed the rate at which ultrasound fails to detect early stage HCCs and factors that affect its performance.

METHODS

We collected information on 1170 consecutive patients included in the Italian Liver Cancer (ITA.LI.CA) database who had Child-Pugh A or B cirrhosis and were diagnosed with HCC during semiannual or annual ultrasound surveillance, from January 1987 through December 2008. Etiologies included hepatitis C virus infection (59.3%), alcohol abuse (11.3%), hepatitis B virus infection (9%), a combination of factors (15.6%), and other factors (4.7%). Surveillance was considered to be a failure when patients were diagnosed with HCC at a stage beyond the Milan criteria (1 nodule ≤5 cm or ≤3 nodules each ≤3 cm).

RESULTS

HCC was found beyond Milan criteria in 34.3% of surveilled patients (32.2% during semi-annual surveillance and 41.3% during annual surveillance; P < .01). Nearly half of surveillance failures were associated with at least one indicator of aggressive HCC (levels of AFP >1000 ng/mL, infiltrating tumors, or vascular invasion and metastases). Semiannual surveillance, female sex, Child-Pugh class A, and α-fetoprotein levels of 200 ng/mL or less were associated independently with successful ultrasound screening for HCC.

CONCLUSIONS

Based on our analysis of surveillance for HCC in patients with cirrhosis, the efficacy of ultrasound-based screening is acceptable. Ultrasound was least effective in identifying aggressive HCC, and at surveillance intervals of more than 6 months.

DNA markers in molecular diagnostics for hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is the one of the leading causes of cancer mortality in the world, mainly due to the difficulty of early detection and limited therapeutic options. The implementation of HCC surveillance programs in well-defined, high-risk populations were only able to detect about 40-50% of HCC at curative stages (Barcelona Clinic Liver Cancer stages 0 & 1) due to the low sensitivities of the current screening methods. The advance of sequencing technologies has identified numerous modifications as potential candidate DNA markers for diagnosis/surveillance. Here we aim to provide an overview of the DNA alterations that result in activation of cancer pathways known to potentially drive HCC carcinogenesis and to summarize performance characteristics of each DNA marker in the periphery (blood or urine) for HCC screening.

Ultrasound induced cancer immunotherapy

Recently, the use of ultrasound (US) has been shown to have potential in cancer immunotherapy. High intensity focused US destruction of tumors may lead to immunity forming in situ in the body by immune cells being exposed to the tumor debris and immune stimulatory substances that are present in the tumor remains. Another way of achieving anti-cancer immune responses is by using US in combination with microbubbles and nanobubbles to deliver genes and antigens into cells. US leads to bubble destruction and the forces released to direct delivery of the substances into the cytoplasm of the cells thus circumventing the natural barriers. In this way tumor antigens and antigen-encoding genes can be delivered to immune cells and immune response stimulating genes can be delivered to cancer cells thus enhancing immune responses. Combination of bubbles with cell-targeting ligands and US provides an even more sophisticated delivery system whereby the therapy is not only site specific but also cell specific. In this review we describe how US has been used to achieve immunity and discuss the potential and possible obstacles in future development.