Contrast-Enhanced Sonographic Appearance of Hepatocellular Carcinoma in Patients with Cirrhosis: Comparison with Contrast-Enhanced Helical CT Appearance

Abstract

We sought to investigate the efficacy of contrast-enhanced sonography using a second-generation contrast agent for the evaluation of hepatocellular carcinoma in patients with cirrhosis by comparing the results to those obtained with contrast-enhanced helical CT. Between October 2002 and March 2003, 74 patients with cirrhosis (60 men and 14 women; age range, 47-80 years; mean age, 67 years) who had a single nodule of hepatocellular carcinoma were selected to be studied from a cohort of 437 patients with cirrhosis. The size range of the 74 nodules was 9-65 mm (mean, 28.2 mm). Twenty-eight (38%) were 20 mm smaller (range, 9-20 mm; mean, 16.6 mm), and 46 (62%) were larger than 20 mm (range, 21-65 mm; mean, 35.2 mm). Contrast-enhanced sonography was performed at a low mechanical index after IV administration of the contrast agent SonoVue. CT scans were obtained in all patients. The enhancement pattern related to tumor hypervascularity was analyzed. The chi-square test was used for statistical analysis. For the 28 hepatocellular carcinomas 20 mm or smaller, contrast-enhanced sonography showed 15 (53.6%) as hypervascular and 10 (35.7%) as avascular; three (10.7%) carcinomas were missed. On CT, 12 (42.9%) of the 28 hepatocellular carcinomas appeared hypervascular, 13 (46.4%) appeared hypovascular, and three (10.7%) were missed. For the 46 hepatocellular carcinomas larger than 20 mm, contrast-enhanced sonography showed 42 (91.3%) as hypervascular and four (8.7%) as avascular. On CT, 35 (76.1%) hepatocellular carcinomas appeared hypervascular, eight (17.4%) appeared hypovascular, and three (6.5%) were missed. Differences between CT appearance of hepatocellular carcinomas and contrast-enhanced sonographic appearance of the carcinomas were not statistically significant. Concordance between contrast-enhanced sonographic and CT appearances was observed in 61 (82.4%) of 74 cases. Contrast-enhanced sonography is similar to CT for detecting hepatocellular carcinoma hypervascularity. It could be complementary to conventional unenhanced sonography for evaluation of liver nodules.