In clinical practice, we often encounter family members asking whether liver cancer is contagious. To answer this question, let’s first talk about how liver cancer occurs? The main causes of liver cancer in China are: chronic viral hepatitis B (about 90% of liver cancer patients in China have a history of hepatitis B virus infection), liver cirrhosis, aflatoxin (mainly produced by moldy peanuts and moldy corn), and drinking water contamination. However, alcoholism, selenium deficiency and genetic susceptibility are also important risk factors. Hepatitis B virus infection is directly related to the occurrence of liver cancer. Measures such as vaccination against hepatitis B, prevention of hepatitis virus infection, active treatment of viral hepatitis and cirrhosis can significantly reduce the incidence of liver cancer. If a patient is transformed from viral hepatitis to hepatitis B, hepatitis B itself may be transmitted during his viral hepatitis stage. As for those who have already been infected with hepatitis B or C virus, they should regularly review liver function, hepatitis markers, methemoglobin, liver ultrasound, etc. to achieve early detection, early diagnosis and early treatment. Therefore, it is said that hepatocellular carcinoma itself is not contagious, but if the patient is also combined with active hepatitis, there is a possibility of infecting hepatitis. If the patient is only a carrier of hepatitis B virus, there are several common ways of virus infection as follows: 1. Mother-to-child transmission It is generally believed that about 1/3 (about 30 million) of hepatitis B surface antigen carriers are from mother-to-child transmission. Due to early infection, more than 90% develop chronic infection. Studies have shown that the risk of chronicity in children infected before 6 years of age is about 30%, while only 5% of those with acquired infection in adulthood become chronic. Mothers who are positive for HBsAg (hepatitis B surface antigen), and especially for HBsAg and HBeAg (hepatitis B e antigen), are highly infectious. The virus is transmitted mainly through the following channels: (1) intrauterine transmission. It is mainly transmitted through the placenta. For pregnant women who are double positive for HBsAg and HBeAg, a monthly injection of high potency hepatitis B immunoglobulin in the second trimester (7, 8 and 9 months) can neutralize the hepatitis B virus in the pregnant woman and reduce the occurrence of intrauterine infection in the fetus. (2) Intrauterine infection. This refers to the infection of the newborn by inhalation of maternal blood, amniotic fluid and vaginal secretions containing hepatitis B virus during delivery; it may also occur through the newborn’s broken skin or mucous membrane. The newborn can be effectively prevented by hepatitis B vaccine combined with hepatitis B immunoglobulin injection after birth. (3) Postnatal infection. Newborns may also be infected by close contact with their mothers. The combination of hepatitis B vaccine and hepatitis B immunoglobulin for newborns can effectively interrupt this infection. 2. Blood transmission and medical transmission Hepatitis B virus is mainly found in the blood of patients, so blood transmission is also an important way. For example: blood transfusion or use of blood products, hemodialysis, accidental stabbing by needles or scalpels, sharing razors, and toothbrushes, tattoos, dental fillings, etc. The semen of male hepatitis B surface antigen carriers is contagious, and the semen of HBsAg-positive patients is injected into the vagina of chimpanzees, and the experiment of hepatitis B infection in chimpanzees suggests that the spouse is a hepatitis B surface antigen carrier, and condoms must be used during intercourse. 4, other ways Hepatitis B can also be father-to-child transmission, mother-to-child transmission is the main way infants are infected with hepatitis B virus, but the survey shows that father-to-child transmission can also cause infant hepatitis B, just not enough attention. Studies have shown that the sperm of hepatitis B patients do carry the hepatitis B virus and HBV-DNA can be present in the cytoplasm of the sperm head, and through fertilization, it can continue to replicate in the offspring cells, and offspring cell infection occurs, causing paternal-infant transmission of hepatitis B. Father-to-child transmission occurs early in life, and surveys have shown that when fathers are double positive for surface antigen and e antigen, the chance of infection in their babies can be over 80%; when fathers are positive for e antibody, the chance of infection in their offspring is about 20%. The chance of father-to-child transmission of hepatitis B virus is even greater than mother-to-child transmission, and it is more likely to cause lifelong carriage. If the patient has chronic hepatitis B with abnormal liver function, antiviral treatment is available. After the patient’s infectiousness is reduced, targeted liver-protective drugs are used under the guidance of a specialist and maintained for a period of time before pregnancy is possible. Through the above explanation, we understand that if a family has a history of hepatitis B or cirrhosis, the chance of developing liver cancer is high. And with the high mortality rate of liver cancer, it is not surprising that a family dies from liver cancer one after another.