Hepatocellular carcinoma in noncirrhotic liver: CT, clinical, and pathologic findings in 39 US residents

PURPOSE: To review clinical, pathologic, and computed tomographic (CT) findings in patients with hepatocellular carcinoma (HCC) in noncirrhotic liver. MATERIALS AND METHODS: Clinical, pathologic, and imaging findings were retrospectively evaluated in 39 patients with HCC in noncirrhotic liver. Helical multiphasic CT scans obtained with 125 mL of contrast medium at a rate of 4 or 5 mL/sec were reviewed for morphologic features such as tumor size, margins, and hemorrhage and degree of enhancement. RESULTS: All patients (25 men, 14 women; mean age, 61 years) were U.S. residents; none had an Asian surname. Twenty-four patients (62%) had no identifiable risk factors; 34 (87%) were symptomatic. HCC was proved and cirrhosis excluded with biopsy in all cases. HCC was moderately (n = 32) or well (n = 6) differentiated in 97% of cases and poorly differentiated in one. Serum a-fetoprotein level was elevated in 26 patients. Large tumors (mean diameter, 12.4 cm) were depicted at CT in all cases. Thirty-two patients had a solitary or dominant mass. At CT, tumor margins were well defined in 21 patients, with a lobulated surface in 33. Calcifications were depicted in 11, hemorrhage in 10, fat in four, dilated intrahepatic bile ducts in 17, and abdominal lymphadenopathy in eight. In 38 patients, tumors were heterogeneous with areas of necrosis. HCC was hypoattenuating on nonenhanced images in 34, heterogeneously hyperattenuating at arterial phase in 38, and hypoattenuating at portal phase in 35 patients. CONCLUSION: HCC developed in the absence of cirrhosis or known risk factors and typically appeared as a large symptomatic hepatic tumor with clinical, laboratory, and CT features that distinguish it from most other hepatic masses.