• Hepatocellular carcinoma

Screening programmes have been developed for the surveillance of patients at risk of hepatocellular carcinoma (HCC; mainly liver cirrhosis) for the detection at an early stage, ie, suspicious liver nodules not larger than 2 cm in diameter often detected by ultrasound. Treatment indication needs a clear diagnosis for which one option is a biopsy often hampered by a relevant rate of false negatives and by a risk of bleeding and malignant seeding. Therefore, for the diagnosis of HCC imaging criteria are preferred requiring contrast enhancement and dynamic imaging. The recent update of the American Association for the Study of Liver Diseases (AASLD) guidelines in 20101 recommends for a nodule greater than 1 cm one single imaging technique to be used among CT and MRI, and in the case of non-diagnostic criteria the choice between a second technique or a biopsy.

Establishing HCC diagnosis at an ideal size of less than 2 cm relates to the transition from low to high grade dysplasia and very early HCC as described by the international working party classification2 and a final international diagnostic consensus.3 From two types of HCC less than 2 cm, early HCC has a vaguely nodular appearance, is well differentiated and corresponds to the very early HCC stage of the Barcelona Clinic Liver Cancer classification, with the absence of microvascular invasion excluding a clear imaging profile for diagnosis. The …