Sometimes we hear about a family having cancer one after another, and there are many cancer patients in the same family. Whenever I see these news, I start to wonder, is cancer hereditary? In fact, cancer is not a standard genetic disease, and cancer genetics does not directly "inherit" the true essence of cancer, but rather transmit cancer susceptibility genes. That is, people with a family history of cancer may not necessarily get cancer, but under the same living conditions, they may have a greater chance of getting cancer than ordinary people and get sick earlier, so they need to do a good job in disease prevention and cancer screening. Why does cancer sometimes occur within the same family? Answer: There may be two possible reasons: 1. Cancer does have a genetic possibility, and due to inheriting familial genetic defects, some people have a significantly increased risk of developing certain cancers. 2. Similar lifestyles and living environments, especially some unhealthy habits such as unhealthy eating, less exercise, smoking, etc., or living in areas with high incidence of gastric and esophageal cancer, while also being contaminated by decoration, may lead to the occurrence of the same type of cancer within the family. These five cancers are relatively more likely to be inherited. 20% - 30% of colon cancer patients have a family history. 20% - 30% of colon cancer patients have a family history of various cancers. Suggestion: If a family member has familial intestinal polyposis, they must go to the hospital for relevant examinations. If a family enjoys eating meat and high protein foods, the risk of developing colorectal cancer in the family will also increase. The most important way to effectively prevent colorectal cancer is to change high fat, high protein, and low fiber dietary habits, actively exercise, and maintain sleep. After the age of 45, on average, a colonoscopy examination is performed every 5-10 years, or an annual fecal occult blood test can be chosen. Individuals affected by genetic factors should also undergo the examination in advance. If frequent bloody stools, frequent bowel movements, mucous stools, and abdominal pain occur, the cause should be promptly identified. 02 Daughters with breast cancer have a 2-3-fold higher risk of breast cancer, and there is a significant genetic tendency, especially among immediate relatives. Generally speaking, if the mother has breast cancer, then the daughter's risk of breast cancer is two to three times higher than other women. Suggestion: For women with family history, breast health examination should be carried out before the age of 30, usually before the age of 35, mainly by B-ultrasound examination; After the age of 35, molybdenum target radiography was performed to detect breast cancer at an early stage. Moreover, women with genetic predispositions should consciously undergo "breast self examination" from the age of 20, especially after menstruation, to detect physical abnormalities in a timely manner. In addition, women with a family history should give birth as soon as possible (before the age of 30) and breastfeed. Women in menopause should not misuse drugs containing estrogen to minimize the risk factors of breast cancer and reduce its incidence rate. 03 Gastric cancer is closely related to genetics, and there is a significant phenomenon of family aggregation in the occurrence of gastric cancer. If at least two people in one or two generations of a family are affected, and one person is under the age of 50, all patients are diffuse, it may be hereditary gastric cancer. Suggestion: Due to hereditary diffuse stomach