Fibrolamellar carcinoma of the liver: an immunohistochemical study of nineteen cases and a review of the literature.

Hepatocellular carcinoma (HCC) is a rapidly fatal neoplasm of high worldwide prevalence. Fibromellar carcinoma (FLC), a variant of HCC, lacks the dismal prognosis of "ordinary" HCC (O-HCC) and is characterized by a diagnostic histologic appearance. The current study analyzes the clinical characteristics, immunohistochemistry, and treatment of nineteen cases of FLC. These data, together with a detailed review of the literature, further characterize this unique variant. FLC affects younger patients and lacks the male predominance of O-HCC. Also, FLC lacks specific association with cirrhosis, hepatitis B virus infection, use of oral contraceptives, and alcohol abuse, all of which are implicated in other hepatic tumors. This, along with differences in serum tumor marker prevalence (AFP, B12 binding protein) suggests that its pathogenesis differs from that of O-HCC. Despite these differences, FLC shares a common differentiation with O-HCC. The increased amounts in FLC of stainable alpha-1-antitrypsin, fibrinogen, and C-reactive protein, all of which are acute phase reactants and normal hepatocyte products, implies better differentiation of FLC cells. Finally, the better prognosis of FLC is supported by this study, since only two of the 19 patients died because of tumor. This contrasts with the reported survival of patients with O-HCC, usually measured in weeks. Hepatic transplantation may hold promise for future patients with "surgically unresectable" FLC as procedure-related complications are overcome.