Can late stage kidney cancer be contagious through saliva?

The question of whether cancer is contagious may sound a bit sensational, but it is not a random guess. Most people who raise this question have two concerns. First, in the same family, although the family members are not related by blood (such as husband and wife), they all have tumors, and they are the same malignant tumors. Second, since it is known that tumors are caused by three major carcinogens: chemical carcinogens, radiation, and certain viruses, can't viruses be transmitted to others like the flu? Does this idea make sense? Is cancer really contagious?

It is well known that some cancers are hereditary. For example, if a mother or sister has breast cancer, her chance of developing breast cancer is three times higher than that of an average woman. In recent years, scientists have discovered that this is related to the presence of certain oncogenes in the genetic material of their cells. But how to explain that family members who are not related by blood suffer from the same cancer? One situation is that people who suffer from the same tumor are often exposed to the same carcinogenic factors. It was reported that both the father-in-law and the son-in-law suffered from lung cancer. After investigation, it was found that the son-in-law took over the job of the father-in-law and worked underground in a mining area, and the concentration of radon and its gas in the mine was too high. Because they were both exposed to this type of radioactive substances for a long time, they developed lung cancer. In addition, both the father-in-law and the son-in-law were smokers, which undoubtedly made things worse and contributed to the formation of the tumor.

There is also a case where a couple both died of liver cancer. After tracing their medical history, it was found that they had both suffered from hepatitis B for many years. As we all know, hepatitis B is caused by the hepatitis B virus, which can be transmitted through blood or other body fluids, including saliva, semen, and vaginal secretions. If hepatitis B is not cured for a long time, it can cause cirrhosis of the liver, and a small number of patients will eventually develop liver cancer.

What is even more alarming is that, regardless of whether a man or a woman has multiple sexual partners, they may bring a risk of certain cancers to the other party. For example, if a man's first wife has cervical cancer, the risk of his second wife having cervical cancer is 3 to 4 times higher than that of ordinary women. Scientists believe that this is related to the possibility that there may be some viruses or carcinogens in the semen ejaculated by men, which infected the second wife. As for the well-known AIDS, "It is caused by the human immunodeficiency virus.

From the above, scientists' answer to whether cancer is contagious is: cancer itself is not directly contagious, because cancer cells do not release infectious factors. However, for example, HIV virus is present in the blood of AIDS patients, and it is difficult to absolutely guarantee that the cells of patients who have liver cancer due to hepatitis B virus infection will not release hepatitis B virus; as for those who have multiple sexual partners, there is a possibility of transmitting HIV and viruses related to cervical cancer. Therefore, in order to prevent such viral infections and related cancers, people should have a clear understanding of the relationship between viruses and cancer, and at the same time, the secretions of such cancer patients, such as sputum, blood, and feces, should be disinfected.