Primary liver cancer (hepatocellular carcinoma for short) is a malignant tumor arising from hepatocytes or intrahepatic bile duct epithelial cells. Early stage hepatocellular carcinoma (small hepatocellular carcinoma) often has no obvious symptoms. Once symptoms such as pain in the liver area, abdominal distension, abdominal mass, jaundice and ascites appear, it is mostly in advanced stage. Therefore, it is difficult for liver cancer patients to be detected at an early stage. But is there nothing that can be done to detect liver cancer in early stage? It is not quite true. Usually, we classify people who meet the following conditions as high-risk groups for liver cancer: 1. aged 35 or above, positive for hepatitis B surface antigen or positive for hepatitis C antibody 2. History of chronic hepatitis for more than 5 years. 3.Patients with confirmed liver cancer in their family. 4. Long-term alcoholic. 5.Hepatitis vertically transmitted by mother. 6. Long-term consumption of pickled, smoked and moldy foods. 7.Patients with long-term work stress, excessive workload or long-term mental depression. 8.Organ transplant patients If you belong to the high-risk group, it is recommended that you should go to relevant medical institutions for 1-4 examinations every year according to the situation, and at present, the more effective examination means for liver cancer are: 1. The diagnosis of hepatocellular carcinoma can be made. 2.B ultrasound imaging can determine whether there are occupying lesions in the liver, and a good ultrasound instrument and an experienced physician can detect liver cancer of 1cm in diameter with careful examination. It can also identify whether the occupying lesion is cystic or solid, and understand the relationship between hepatocellular carcinoma and important intrahepatic vessels as well as the dissemination and infiltration of intrahepatic and adjacent organs. To show whether there are tumor emboli in the intrahepatic portal vein and its branches, etc. CT (computed tomography) and magnetic resonance imaging are important tools for further diagnosis of hepatocellular carcinoma; CT is one of the most sensitive methods for detecting hepatocellular carcinoma, and with appropriate enhancement, the detection rate of lesions can be over 90%. Sometimes, it is still difficult to diagnose small hepatocellular carcinoma, isodense hepatocellular carcinoma and atypical hepatocellular carcinoma with CT. It should be combined with other examinations for comprehensive analysis and diagnosis.