Role of MRI in Detecting and Characterizing Small Hepatic Focal Lesions

Background Despite the recent advances in liver imaging, the detection and characterization of small hepatic focal lesions is still a real challenge. Particularly in cancer patients where the characterization of a small HFL as thus the precise tumor staging is critical for optimal treatment planning. Aim of the Work To explore the effectiveness, and hence the clinical utility, of MRI detection and characterization of small focal hepatic lesions either only discovered on MRI or as a further work up of CT/US-indeterminate lesions. Patients and Methods We reviewed our database for individuals who underwent liver MR imaging between March 2018 and March 2019 for the evaluation of small hepatic lesions that were discovered for the first time or had been previously visualized on routinely performed CT and had been considered indeterminate. Results The present study included 44 patients of which 26 were males (59.1%) and 18 were females (40.9%). The age range of the study group was 19 to 77 years. The mean age for Malignant lesions was 51 years. The right lobe of liver was involved in 23 cases (52.3%), left lobe in 5 cases (11.4%) and both lobes in 16 cases (36.4%). There were 30 (68.18%) benign, 13 (29.54%) malignant lesions and 1 (2.3%) indeterminate, hemangiomas were predominant in benign lesions whereas hepatocellular carcinomas were predominant in malignant lesions. N'TRI could characterize 92% cases. Conclusion The diagnostic process of small hepatic focal lesions, either detection or characterization or both, continues to represent a challenge. Contrast-enhanced MR can accurately detect and characterize majority of small hepatic focal lesions.

The Use of the Apparent Diffusion Coefficient (ADC) for Characterization and Differentiation of Focal Hepatic Lesions in Noncirrhotic Patients.

PURPOSE Diffusion-weighted imaging (DWI) is a MRI technique that, although relatively recent, has shown promise for the evaluation of focal hepatic lesions, providing information both on qualitative and quantitative parameters. The present study was designed to analyze the role of DWI, particularly the ADC (apparent diffusion coefficient), in differentiating benign solid liver lesions from malignant ones in a sample of noncirrhotic patients. METHODS We conducted a retrospective analysis of MRI scans performed at a tertiary hospital in Porto Alegre, Rio Grande do Sul, Brazil, from 2015 to 2018. The distribution of lesions into benign vs. malignant groups was determined by imaging criteria and/or histological analysis. ADC were obtained for each lesion.RESULTS Overall, 118 focal liver lesions were evaluated, with 78 benign and 40 malignant. The mean ADC value was 1.420×10−3 mm2/s for benign lesions versus 1.130×10−3 mm2/s for malignant lesions (p<0.001). ROC curve analysis showed an area under the curve of 0.79, optimal cutoff point of 1.19×10−3 mm2/s for discriminating between malignant and benign lesions, sensitivity and specificity of 75% and 73.1%.CONCLUSIONS We demonstrate the appropriateness of ADC for characterization of benign solid lesions of the liver and to distinguish these masses from malignant metastatic lesions.

Ascitic Fluid Cytokines in Chronic Liver Disease: A Possible Prognostic Tool

Introduction: Malignant ascites results from imbalance between protein in the peritoneal cavity and absorption of fluids via the lymphatic system. More than twenty interleukins are known to play an important role in the protection against tumors. Materials and methods: Ascitic fluid IL1B, IL2, IL4, IL6, IL10, TNFα, and IFNγ levels were assessed in forty-five patients with liver cirrhosis and ascites as judged by histopathological and ultra-sonographic findings. They were divided into two groups according to presence of hepatic focal lesions. Ten patients with focal hepatic lesions were randomly selected and subjected to analysis of serum levels of IL2 and IL10. Results: Ascitic fluid IL-4, IL-6 and IL-10 levels were found to be significantly higher in patients with hepatocellular carcinoma than patients with cirrhosis. TNFα, and IFNγ were also found to be higher in hepatocellular carcinoma than patients with cirrhosis but with no significance. On the other hand, there was no significant difference in levels of IL1B and IL2 between the two groups. Ascitic fluid IL2 and IL10 levels were found to be higher in ascitic fluid than in serum of the same patients. Conclusion: Ascitic fluid levels of IL-4, IL-6 and IL-10 are higher in hepatocellular carcinoma patients than patients with cirrhosis alone. Levels of ascitic fluid IL2 and IL10 were proved to be a better prognostic tool than their levels in sera of the same patients. To conclude; patients with cirrhosis may be subjected to schedualed examination of ascitic fluid cytokine to predect transformation into hepatocellular carcinoma.

Role of MRI in Evaluation of Focal Liver Lesions: A Cross-sectional Study

Introduction: The non-invasive diagnosis of liver lesions is usually achieved with contrast material-enhanced computed tomography and Magnetic Resonance (MR) imaging. Dynamic three dimensional gradient-recalled-echo MR imaging provides dynamic contrast-enhanced thin-section images with fat saturation and a high signal-to-noise ratio and is excellent for the evaluation of various focal hepatic lesions. Aim: To explore the effectiveness and hence the clinical utility of plain and contrast MR characterisation of focal hepatic lesions in patients and their correlation with the histopathological findings. Materials and Methods: The present study was a multicenteric study done on both Inpatients and Outpatients of Department of Radiology of Tertiary care hospitals in Bengaluru, from January 2020 to August 2020. A total of 42 patients diagnosed with focal liver lesions by Ultrasonography were included in this study. Plain MRI study was done by using spin echo technique and contrast MRI study was done after rapid bolus injection (0.1 mmol/kg body weight) of gadolinium dimeglumine. Pathological and post-operative histopathological findings were noted. Microsoft excel software was used for data analysis and tables were prepared for comparison of collected data. Specificity and sensitivity were calculated for diagnostic accuracy of MRI. Results: This study included forty-two patients in total, twenty-five male and seventeen female patients, in age group of 15 to 84 years with a mean age of 48 years. Metastasis and Hepatocellular Carcinoma (HCC) were most common malignant lesions in liver while Hemangiomas were most common benign lesions followed by simple and complex cysts and hepatic adenoma. The present study calculated the specificity and sensitivity of MRI of focal hepatic lesions and correlated the findings clinically, pathologically and histopathologically. The specificity of MRI for characterisation of focal liver disease was high (90.4%). Specificity of MRI for HCC was found to be 96.7 % and that for metastasis was 97% while sensitivity for Haemangiomas is found to be 100%.MRI is superior compared to other modalities like ultrasound and CT in having high spatial resolution. Multiple sequences like T1, T2 and fat suppression techniques like IN PHASE, OUT OF PHASE helps in demonstrating lesion characters like architecture, margin, haemorrhage, fat component and vascular invasion of the lesions. Conclusion: MRI is valuable for the characterization of focal liver lesions detected on Ultrasonography. Basic MRI sequences along with chemical shift imaging sequences and dynamic contrast imaging has significant role in characterising the focal liver lesions. Despite that, It should be the modality choice for the lesions which are undetected or doubtful on ultrasound and CT examinations.

Characterization of Immature Myofibroblasts of Stellate Cell or Mesenchymal Cell Origin in D-Galactosamine-Induced Liver Injury in Rats

Lesions of D-galactosamine (D-GalN)-induced hepatotoxicity resemble those of human acute viral hepatitis. This study investigated hepatic mesenchymal cells including hepatic stellate cells (HSCs) and myofibroblasts in D-GalN-induced hepatotoxicity. Rats, injected with D-GalN (800 mg/kg body weight, once, intraperitoneally) were examined on post single injection (PSI) at 8 hours and days 1 to 5. Lesions consisting of hepatocyte necrosis and reparative fibrosis were present diffusely or focally within the hepatic lobules on PSI days 1 and 2, and then the injury recovered on PSI days 3 and 5. Myofibroblasts expressing vimentin, desmin, and α-smooth muscle actin (α-SMA) were present in the lesions. Double immunofluorescence showed that myofibroblasts reacted simultaneously to vimentin/α-SMA, desmin/α-SMA, and desmin/vimentin; furthermore, myofibroblasts reacting to vimentin, desmin, and α-SMA also co-expressed glial fibrillary acidic protein (GFAP), a marker of HSCs. Additionally, GFAP-expressing myofibroblasts reacted to nestin and A3 (both are markers of immature mesenchymal cells). Cells reacting to Thy-1, a marker for immature mesenchymal cells, also appeared in fibrotic lesions. In agreement with the myofibroblastic appearance, mRNAs of fibrosis-related factors (TGF-β1, PDGF-β, TNF-α, Timp2, and Mmp2) increased mainly on PSI days 1 and 2. Myofibroblasts with expression of various cytoskeletal proteins were present in diffuse or focal hepatic lesions, and they might be derived partly from immature HSCs and from immature mesenchymal cells.

SIUMB recommendations for focal pancreatic lesions

Contrast-enhanced ultrasonography (CEUS) is increasingly being performed in Italy and Europe, particularly in the field of hepato-gastroenterology. Initially, it was mainly carried out to characterize focal hepatic lesions, but, since then, numerous studies have demonstrated its efficacy in the differential diagnosis of focal pancreatic pathologies (D’Onofrio et al. in Expert Rev Med Devices 7(2):257–273, 2010; Vidili et al. in J Ultrasound 22(1):41–51, 2019). The purpose of this paper is to provide Italian Medical Doctors with recommendations and thereby practical guidelines on the management of these patients. The present paper reports the final conclusions reached by the SIUMB guideline commission. This paper addresses particularly percutaneous ultrasound (US) examination (transabdominal US) and is drawn up specifically for publication.