Malignidad primaria del hígado

RESUMO

The most common liver tumor in USA and most of the western world is metastasic. Primary hepatic tumors can derive from hepatocytes (hepatocarcinoma), biliary ducts (cholangiocarcinoma) and Kupffer's cells (hemangiosarcoma). The most common primary liver tumor in the world is the hepatocarcinoma, this is due to the high prevalence of the lesion in many areas of Africa and Asia, although it is unusual in the western hemisphere. Risk factors for hepatocarcinoma include: HBsAg carrier state, hepatitis C infection, cirrhosis of the liver, alcoholic liver disease, aflatoxin exposure, thorium dioxide, pesticides, anabolic steroids and hemochromatosis. The regenerative nodule can be considered as a preneoplastic lesion. Several tumoral markers have been found helpful in the diagnosis of this tumor: the classic one AFP is present only in 43 percent of the cases, HBsAg in studies in Taiwan in 58 percent of non neoplastic hepatocytes, AAT in 70 percent of the patients. These marquers are expressed in the liver cell in several forms: granulofibrilar occupying most of the cytoplasm and diffuse granular mainly in malignant hepatocytes. Immunoperoxidase stain shows a thick expression of the granular antigen in regenerating cells: this is true for AFP, AAT and HBsAg. The morphology of the tumor is multicentric in cirrhotic livers or focal in normal ones. Characteristically has a notorius tendency to invade the venous system and generally can appear as: a) nodular, b) massive, c) diffuse. The most common histologic pattern is the trabecular-pseudoglandular. The OMS classification of this lesion described 12 different types. In general the prognosis is very poor with the exception of the fibrolamelar type seen in young people that frequently can be resected...