Hepatocellular carcinoma occurring in nonfibrotic liver: epidemiologic and histopathologic analysis of 80 French cases.

Hepatocellular carcinoma (HCC) occurring in nonfibrotic liver represents a rare, ill-defined subgroup of HCC without cirrhosis in which mechanisms of hepatocarcinogenesis remain unclear. The aim of our study was to assess epidemiological factors and detailed histopathologic changes in the nontumoral liver of patients developing such tumors. Of 330 HCCs resected in our institution between 1985 and 1998, we retrospectively analyzed 80 cases (53 men, 27 women; mean age, 51 +/- 16 years) in which the nontumoral liver showed no (n = 28) or minimal (n = 52) portal fibrosis without any septal fibrosis. In the group with no portal fibrosis there was no male predominance, and patients were significantly younger (44 +/- 19 years vs. 54 +/- 14 years) than those with minimal portal fibrosis. Sixty-seven tumors were typical HCCs, 8 were of fibrolamellar type, and 5 were hepatocholangiocarcinomas. Mean tumor size was 10 +/- 5 cm. Risk factors for HCC development were found in 30 patients: hepatitis B (n = 17) or C (n = 2) virus infections, alcohol consumption (n = 11), and hemochromatosis (n = 1). In the nontumoral liver, periportal and lobular necrosis, mild portal inflammation, steatosis, and iron overload were present in 15%, 57%, 52%, and 54% of cases, respectively. Liver cell changes were noted in 6%. This study emphasizes the need for strict criteria to classify HCC without cirrhosis. HCC in nonfibrotic liver is a distinct subgroup in which nontumoral liver shows nonspecific minimal changes without regeneration or premalignant lesion. Etiologic factors are often unidentified, although presence of HBV infection in 21% suggests a direct oncogenic role of this virus.