Department of Radiology, Seoul National University College of Medicine
ABSTRACT
PURPOSE : The prognosis of hepatocellular carcinoma (HCC) is very poor because of the difficulty in earlydetection and association with the liver cirrhosis. Because the surgical resection or transarterialchemoembolization is the most effective treatment, the detection of the small HCCs is important. The purpose ofthis study was to assess the frequencies of a suggestive sonographic morphology of small HCC. MATERIAL & METHODS :In 222 patients with small HCCs less than 5 cm in diameter, each sonographic feature of 274 nodules was analyzed.HCCs were diagnosed pathologically (n = 83) or by elevated serum alpha-fetoprotein levels and characteristicangiographic δ Lipiodol CT findings (n = 191). The diameters of the tumors were as follows : ≤ 2 cm (n = 90),2∼3 cm (n = 87), and 3∼5 cm (n = 97). The frequencies of sonographic morphology of small HCCs includingechopattern, peripheral hypoechoic halo, lateral shadow, posterior acoustic enhancement, and the mosaic patternwere assessed. For statistical analysis of the differences of echopattern, Chi-square test was used and forevaluation of the differences of the sonographic characteristics according to the tumor size, Friedman Two-WayANOVA test was used. RESULTS : Overall, characteristics of small HCCs less than 5 cm were peripheral halo (70%),posterior enhancement (43%), and mosaic pattern (39%). In small HCCs less than 3 cm hyperechoic masses are morecommon than hypoechoic masses, which is different from previous peports. The smaller the mass, the more frequentthe incidence of high or low echopattern. Mixed echopattern, peripheral halo, and mosaic pattern increased isoecho, lateral shadow, and posterior acoustic enhancement between 2 cm, 2∼3 cm, and 3∼5 cm size nodules.CONCLUSION : The understanding about the sonographic characteristics of small HCCs according to the size may beuseful for the detection and characterization of the small HCCs.