Hepatocellular carcinoma in adenomatous hyperplasia: detection with contrast-enhanced US with carbon dioxide...

Adenomatous hyperplasia (AH) of the liver is considered a precancerous lesion because hepatocellular carcinoma (HCC) has been found in nodules of AH at histologic examination. Contrast material-enhanced ultrasound (US) with intraarterial infusion of carbon dioxide microbubbles was performed in four patients with HCC in AH lesions. In all four patients, a "hyperechoic focus in an area of hypoechoic change" in relation to the adjacent liver was demonstrated, compatible with the minimal vascular change associated with neoplastic transformation and carcinoma development. Because early detection of the minute cancer foci that may develop in an AH nodule is clinically important, this contrast-enhanced US technique may be a useful tool for the detection of these associated lesions.