Follow-up Strategies in Focal Liver Lesions and Treatment Methods

Today, advances in cross-sectional imaging have led to the detection and early recognition of incidental/focal liver lesions (FCL). In approximately 17,000 cases of chest CT, incidental liver lesions were found in 6% [1]. In general, FCL consists of hepatocytes, biliary epithelium, mesenchymal tissue, connective tissue, or metastasized cells from distant sites. Most incidental lesions are benign, some may require careful management and treatment. In evaluating the lesion, the patient's clinical history, underlying disease and age factor should be considered. FCL can be detected at a rate of 10-30% in normal healthy and chronic liver disease patients, and even in oncology patients with malignancy, FCLs can be highly benign (50-80%)

Can optimized model-based iterative reconstruction improve the contrast of liver lesions in CT?

Background Computed tomography is a standard imaging procedure for the detection of liver lesions, such as metastases, which can often be small and poorly contrasted, and therefore hard to detect. Advances in image reconstruction have shown promise in reducing image noise and improving low-contrast detectability. Purpose To examine a novel, specialized, model-based iterative reconstruction (MBIR) technique for improved low-contrast liver lesion detection. Material and Methods Patient images with reported poorly contrasted focal liver lesions were retrospectively reconstructed with the low-contrast attenuating algorithm (FIRST-LCD) from primary raw data. Liver-to-lesion contrast, signal-to-noise, and contrast-to-noise ratios for background and liver noise for each lesion were compared for all three FIRST-LCD presets with the established hybrid iterative reconstruction method (AIDR-3D). An additional visual conspicuity score was given by two experienced radiologists for each lesion. Results A total of 82 lesions in 57 examinations were included in the analysis. All three FIRST-LCD algorithms provided statistically significant increases in liver-to-lesion contrast, with FIRSTMILD showing the largest increase (40.47 HU in AIDR-3D; 45.84 HU in FIRSTMILD; P < 0.001). Substantial improvement was shown in contrast-to-noise metrics. Visual analysis of the lesions shows decreased lesion visibility with all FIRST methods in comparison to AIDR-3D, with FIRSTSTR showing the closest results ( P < 0.001). Conclusion Objective image metrics show promise for MBIR methods in improving the detectability of low-contrast liver lesions; however, subjective image quality may be perceived as inferior. Further improvements are necessary to enhance image quality and lesion detection.

Multiparametric Ultrasound Approach Using a Tree-Based Decision Classifier for Inconclusive Focal Liver Lesions Evaluated by Contrast Enhanced Ultrasound

Background: Multiparametric ultrasound (MPUS) is a concept whereby the examiner is encouraged to use the latest features of an ultrasound machine. The aim of this study was to reanalyze inconclusive focal liver lesions (FLLs) that had been analyzed via contrast enhanced ultrasound (CEUS) using the MPUS approach with the help of a tree-based decision classifier. Materials and methods: We retrospectively analyzed FLLs that were inconclusive upon CEUS examination in our department, focusing our attention on samples taken over a period of two years (2017−2018). MPUS reanalysis followed a three-step algorithm, taking into account the liver stiffness measurement (LSM), time–intensity curve analysis (TIC), and parametric imaging (PI). After processing all steps of the algorithm, a binary decision tree classifier (BDTC) was used to achieve a software-assisted decision. Results: Area was the only TIC-CEUS parameter that showed a significant difference between malign and benign lesions with a cutoff of >−19.3 dB for washout phenomena (AUROC = 0.58, Se = 74.0%, Sp = 45.7%). Using the binary decision tree classifier (BDTC) algorithm, we correctly classified 71 out of 91 lesions according to their malignant or benignant status, with an accuracy of 78.0% (sensitivity = 62%, specificity = 45%, and precision = 80%). Conclusions: By reevaluating inconclusive FLLs that had been analyzed via CEUS using MPUS, we managed to determine that 78% of the lesions were malignant and, in 28% of them, we established the lesion type.

THE RESULTS OF SURGICAL TREATMENT OF VARIOUS FORMS OF FOCAL LESIONS OF THE LIVER

Объем резекции очень важен при хирургическом лечении очаговых заболеваний печени. Операции с использованием современного технического оборудования позволили снизить количество осложнений с 42,9% до 19,7%, а при масштабных резекциях - с 54,9% до 20,9%. Общая послеоперационная смертность снизилась с 7,1% до 2,5%. Долгосрочные улучшения результатов (с 74,3% до 89,6%) и снижение неудовлетворительных результатов с 17,6% до 5,8% могут быть достигнуты путем применения радикальных методов хирургического лечения различных форм очаговых поражений печени. У пациентов с заболеваниями печени может быть возможно улучшить выживаемость два и три года с 37,5% до 53,3% и с 25 до 40%. The volume of resection is very important in the surgical treatment of focal liver diseases. Operations using modern technical equipment allowed to reduce the number of complications from 42.9% to 19.7%, and with large-scale resections - from 54.9% to 20.9%. Total postoperative mortality decreased from 7.1% to 2.5%. Long-term improvement of results (from 74.3% to 89.6%) and a decrease in unsatisfactory results from 17.6% to 5.8% can be achieved by applying radical methods of surgical treatment of various forms of focal liver lesions. In patients with liver disease, it may be possible to improve survival for two and three years from 37.5% to 53.3% and from 25 to 40%.

VueBox® for quantitative analysis of contrast-enhanced ultrasound in liver tumors

Dynamic contrast-enhanced ultrasound (DCE-US) enables quantification of tumor perfusion. VueBox is a platform independent external software using DICOM cine loops which objectively provides various DCE-US parameters of tumor vascularity. This review summaries its use for diagnosis and treatment monitoring of liver tumors. The existing literature provides evidence on the successful application of Vuebox based DCE-US for characterization and differential diagnosis of focal liver lesions, as well as on its use for monitoring of local ablative therapies and of modern systemic treatment in oncology.

Ultrasound contrast agent Sonazoid for the diagnosis of hepatic epithelioid angiomyolipoma: a case report

Background An angiomyolipoma usually occurs in the kidneys and rarely in the liver. Hepatic epithelioid angiomyolipoma (HEAML), a rare variant of angiomyolipoma, possesses malignant potential and mimics the imaging features of hepatocellular carcinoma. Sonazoid® (perfluorobutane microbubbles), a new contrast agent that facilitates hepatic parenchyma-specific Kupffer phase imaging on contrast-enhanced ultrasonography (CEUS), is useful for the detection and characterization of focal liver lesions. Case presentation A 30-year-old man with HEAML underwent CEUS using Sonazoid®, in which new concepts for ultrasonography-based differentiation between HEAML and hepatocellular carcinoma were applied. Conclusions This case report provides clinicians and radiologists with a reference for distinguishing HEAML from hepatocellular carcinoma based on CEUS using Sonazoid®.

Application Progress of Gd-EOB-DTPA-Enhanced MRI T1 Mapping in Hepatic Diffuse Diseases

Background: In recent years, T1 mapping imaging based on Gd-EOB-DTPA-enhanced magnetic resonance imaging (MRI) has resulted in new research and clinical applications in hepatic diseases. Objective: The objective of the study is to analyze, prospect, and summarize the Gd-EOB-DTPA-enhanced MRI T1 mapping technology in hepatic diseases in recent years. Main Findings: Gd-EOB-DTPA-enhanced T1 mapping has been used more frequently in liver diseases regardless of 1.5T or 3.0T MRI equipment. Volume interpolated body examination (VIBE) mapping sequence seems to be the recommended MRI scan sequence. In the evaluation of T1 value on liver function, the hepatobiliary phase 10 minutes after enhancement is the recommended time point. The fat fraction and hepatic steatosis grade based on MRI-derived biomarkers are easier to implement and popularize than a liver biopsy. Gd-EOB-DTPA-enhanced MRI T1 mapping can not only be used to evaluate the degree of liver injury, the stage of liver fibrosis, and the liver reserve function of patients with liver cirrhosis but also to distinguish focal liver lesions and predict the differentiation degree of hepatocellular carcinoma. At the same time, it has some value in predicting tumor immunohistochemical indexes, such as Ki67, CD34. Conclusion : Gd-EOB-DTPA-enhanced MRI T1 mapping has great potential in the application of diffuse and focal liver lesions. It is a quantitative study, trying to select homogeneous research objects and try to use the same standards in scanning sequence and scanning time, especially for the study of liver function, which is a focus of future research. The research on the relationship between T1 value and tumor immunohistochemical indexes is worth consideration.

Role of Contrast-Enhanced Ultrasonography in Hepatocellular Carcinoma by Using LI-RADS and Ancillary Features: A Single Tertiary Centre Experience

Clinical utility of ancillary features (AFs) in contrast-enhanced ultrasound (CEUS) Liver Imaging Reporting and Data System (LI-RADS®) is yet to be established. In this study, we assessed the diagnostic yield of CEUS LI-RADS and AFs in hepatocellular carcinoma (HCC). We retrospectively included patients with risk factors for HCC and newly diagnosed focal liver lesions (FLL). All lesions have been categorized according to the CEUS LI-RADS v2017 by an experienced sonographer blinded to clinical data and to the final diagnosis. From a total of 143 patients with 191 FLL, AFs favoring HCC were observed in 19.8% cases as hypoechoic rim and in 16.7% cases as nodule-in nodule architecture. From the total of 141 HCC cases, 83.6% were correctly classified: 57.4%- LR-5 and 26.2%- LR-4. In 9.21% cases, CEUS indicated LR-M; 2.12% cases- LR-3. The LR-5 category was 96.2% predictive (PPV) of HCC. LR-5 had 60.4% sensitivity and 93.6% specificity. PPV for primitive malignancy (LR-4 + LR-5) was 95.7%, with 88% sensitivity, 89.3% specificity and 88.4% accuracy for HCC. LR-4 category had 94.8% PPV and 26.2% sensitivity. CEUS LR4 + LR5 had 81,8% sensitivity for HCCs over 2 cm and 78.57% sensitivity for smaller HCCs. CEUS LR-5 remains an excellent diagnostic tool for HCC, despite the size of the lesion. The use of AFs might improve the overarching goal of LR-5 + LR-4 diagnosis of high specificity for HCC and exclusion of non-HCC malignancy.