When I see patients with liver cancer, one of the questions I am often asked by family members is “will liver cancer be contagious and hereditary”. In reality, there are many people who have similar concerns. In order to answer this question correctly and comprehensively, I believe that it cannot be answered with a simple “will” or “won’t”, but should be considered in many aspects to help people have a more comprehensive understanding of liver cancer and preventive measures. Medically, liver cancer is divided into two categories: primary liver cancer and secondary liver cancer, which are completely different diseases and should not be mixed together. Primary liver cancer refers to the tumor originated from the liver, i.e. the liver itself has problems and the root of the disease is in the liver, so most of the liver cancer we usually talk about refers to primary liver cancer, among which hepatocellular liver cancer is the most common; secondary liver cancer, also known as liver metastasis, refers to malignant tumors whose primary lesion is outside the liver and the tumor cells spread to the liver through blood, lymph or directly. Before the occurrence of liver metastasis, the liver itself can be free of any problem and the root of the disease is not in the liver. In this article, I am going to explain the question of whether primary liver cancer is contagious and hereditary. According to the latest information from the World Health Organization (WHO), the number of primary liver cancer in China accounts for more than half of the total number of cases worldwide, and the number of new cases of liver cancer is nearly 400,000 every year, ranking fifth in incidence and second in mortality of malignant tumors. One of the reasons for the high incidence of liver cancer in China is mainly because of the high rate of hepatitis B virus (HBV) infection in China. If there are bad habits such as smoking and drinking on top of chronic hepatitis B infection, liver cancer will easily occur, so I strongly recommend that people with high-risk factors (hepatitis B or C virus infection, long-term alcohol consumption, smoking, severe fatty liver, family history of tumor, etc.) must undergo regular screening so that tumors can be detected early. So, is primary liver cancer contagious and hereditary or not? Infection simply means that a certain disease is transmitted from one person to another through a certain way, such as influenza, measles and mumps are all infectious diseases. Infection must have three conditions: the source of infection, transmission channels and susceptible people, one of the three is indispensable. Current epidemiological survey data show that liver cancer patients are not infectious, otherwise surgeons like me who have long term contact with liver cancer patients would have a much higher probability of getting liver cancer than the general population! Moreover, hospitals do not need to take isolation measures for liver cancer patients, so it is safe to say that liver cancer is not a contagious disease. Whether the disease that causes liver cancer is contagious or not is a different question! As mentioned above, the high incidence of primary liver cancer in China is mainly due to chronic liver disease caused by hepatitis B virus (HBV) infection, which is one of the statutory infectious diseases in China. Therefore, when contacting hepatitis B patients, special attention should be paid to avoid contacting exposed skin or mucous membrane with body fluids of hepatitis B patients, especially when there are open wounds on the skin or mucous membrane, while daily contact without blood exposure such as study, work or life contact is not risk of hepatitis B infection. In addition, for those who are often exposed to liver cancer combined with hepatitis B, if they do not have hepatitis B antibody in their blood, it is recommended to get hepatitis B vaccination as soon as possible. Although liver cancer itself is not contagious, why do some families have more than two liver cancer patients at the same time? Is liver cancer hereditary? The heart that I just put down was raised again at once. Although modern medicine has been very advanced, there are still many unsolved problems. Many malignant tumors, including liver cancer, are still considered to have certain genetic tendency. It has been found that in addition to the aggregation of hepatitis virus infection in liver cancer families, similar dietary habits and lifestyles of a family can also increase the chance of developing cancer. Therefore, at this stage, we cannot completely exclude the role of genetic factors in the development of liver cancer. When a family member suffers from liver cancer, we must pay more attention to our own health while taking care of the patient, because there are still many measures to help us reduce the occurrence of liver cancer: 1) prevent infection with hepatitis virus, vaccination, and avoid close contact with body fluids of liver disease patients; 2) stay away from bad lifestyle, especially quit smoking and alcohol; 3) do not eat moldy, spoiled or burnt food, minimize eating pickled and processed meat products, and drink clean water. 4.Eat a balanced diet, eat more fresh vegetables and fruits to ensure the intake of various nutrients as needed; 5.Live a regular life, get up and down on time, and strengthen physical exercise; 6.Avoid mood swings and maintain an optimistic mental state; 7.Avoid overwork, ensure sufficient sleep, and do not stay up late; 8.Regular medical checkups, especially for high-risk groups.