Hepatocellular Carcinoma: State of the Art Imaging and Recent Advances

The incidence of hepatocellular carcinoma(HCC)is increasing,with this trend expected to continue to the year 2030.Hepatocarcinogenesis follows a predictable course,which makes adequate identification and surveillance of at-risk individuals central to a successful outcome.Moreover,imaging is central to this surveillance,and ultimately to diagnosis and management.Many liver study groups throughout Asia,North America and Europe advocate a surveillance program for atrisk individuals to allow early identification of HCC.Ultrasound is the most commonly utilized imaging modality.Many societies offer guidelines on how to diagnose HCC.The Liver Image Reporting and Data System(LIRADS)was introduced to standardize the acquisition,interpretation,reporting and data collection of HCC cases.The LIRADS advocates diagnosis using multiphase computed tomography or magnetic resonance imaging(MRI)imaging.The 2017 version also introduces contrast-enhanced ultrasound as a novel approach to diagnosis.Indeed,imaging techniques have evolved to improve diagnostic accuracy and characterization of HCC lesions.Newer techniques,such as T1 mapping,intravoxel incoherent motion analysis and textural analysis,assess specific characteristics that may help grade the tumor and guide management,allowing for a more personalized approach to patient care.This review aims to analyze the utility of imaging in the surveillance and diagnosis of HCC and to assess novel techniques which may increase the accuracy of imaging and determine optimal treatment strategies.

CT of hepatocellular carcinoma in non-alcoholic fatty liver disease: imaging characteristics and inter-rater agreement

Aim:To determine the computed tomography(CT)features of non-alcoholic fatty liver disease(NAFLD)associated hepatocellular carcinoma(HCC).Methods:In this institutional review board approved study,we reviewed 38 patients with NAFLD(68.4%male;mean age 63 years)with histology confirmed HCC and triphasic liver CT.CT images were independently reviewed by four readers blinded to clinical and pathology data.The reviewers assessed HCC for arterial phase hyper enhancement(APHE),portal venous phase washout(PVWO),delayed phase washout(DPWO),and enhancing capsule.Features of cirrhotic morphology and portal hypertension(PH)were also evaluated.The final CT features were determined by majority and a fifth reader reviewed cases lacking majority.Inter-rater agreement was determined by prevalence-adjusted kappa.Results:Mean HCC size was 3.6±2.8 cm(range,1.1-16.0 cm).The HCCs showed APHE in 92.1%,PVWO in 55.3%,DPWO in 81.6%,and enhancing capsule in 44.7%.Cirrhotic morphology was present in 65.8%and PH in 63.2%.Inter-rater agreement was moderate to almost perfect for APHE(0.74-1.0),cirrhosis(0.79-0.89),and PH(0.79-0.95),weak to perfect for DPWO(0.47-0.95)and poor for PVWO(0-0.42). ;Conclusion:NAFLD associated HCC demonstrate less frequent portal venous washout on CT which may affect their imaging diagnosis.