(I) Causes of hepatocellular carcinoma The causes of hepatocellular carcinoma, after many studies, have been recognized to some extent, but its causes are not yet clear. Current studies believe that the causative factors: 1. cirrhosis hepatocellular carcinoma patients about 80% combined with hepatitis cirrhosis, and most patients are large nodular cirrhosis, which may be due to hepatocyte degeneration necrosis, interstitial connective tissue proliferation, fibrous septum formation, residual hepatocyte nodular regeneration, and This may be due to degenerative necrosis of hepatocytes, proliferation of interstitial connective tissue, formation of fibrous septum, nodular regeneration of residual hepatocytes, and formation of lobules. The incidence of hepatocellular carcinoma is significantly higher in HbsAg-positive patients than in HbsAg-negative patients, and hepatitis C is also closely related to the occurrence of hepatocellular carcinoma. 3.After food containing aflatoxin is ingested, it is absorbed through the digestive tract and reaches the liver, causing hepatocyte degeneration and necrosis, followed by hyperplasia and carcinogenesis. 4.Chemical carcinogens now clearly include nitrate and nitrite, etc. The occurrence of hepatocellular carcinoma is generally related to the low immune function of antibody, especially to the low cellular immune function. (II) Pathogenesis Hepatoblastoma is mostly a single focal point and located in the right lobe of the liver. In 1967, Ishak and Gkunz divided hepatoblastoma into two types: epithelial and epithelial-mesenchymal type. The purely epithelial type of tumor is nodular, uniform in section, and consists of two types of cells. One is the fetal type cells, which resemble fetal liver cells and are often arranged in two cell-thick irregular liver plates. The cells vary in size, but are often smaller than normal hepatocytes, with eosinophilic cytoplasm and glycogen content. The nuclei are round or oval and basophilic, with a few nuclear divisions. The second is an embryonic type of cells, slightly less differentiated, arranged in bundles, small and darkly stained, with little cytoplasm and little or no glycogen. Nuclear staining is deep and nuclear schizophrenia is common. Mixed tumor sections are lobulated and separated by collagen fibers, and fetal and embryonic cells can be seen in areas supported by reticular fibers. The primitive mesenchymal cells are long and spindle-shaped with little cytoplasm, and bone-like tissue can be seen. In recent years, the CCSG (Children’sCancerStudyGroup), SWOG (Southwest Oncology Group) and POG (Paediatric Oncology Group) have classified hepatoblastoma into fetal, fetal, and embryonic types based on the recommendations of Weinber and Finnegold. hepatoblastoma into fetal, embryonal, coarse beam and small cell undifferentiated (mesenchymal) types. Hepatocellular carcinoma contains well-differentiated large polygonal cells with eosinophilic cytoplasm, and the cells form a hepatic cord structure surrounded by vascular sinuses. Both types of tumors have foci of extramedullary erythropoietic hyperplasia and also invade the right lobe of the liver, with about half of the patients having tumors invading the right and left lobes or being multicentric. Metastasis to the lung is most common, and local spread within the abdominal cavity is not uncommon. Rarely, metastasis to the central nervous system is seen.