There are various factors that cause cancer, but bad habits are often closely related to the development of cancer. For example, alcoholism is not only harmful to liver, but also the incidence of esophageal cancer is 50 times higher in heavy drinkers than in non-drinkers. Smoking is also an important cancer-causing factor, about 20% of cancer deaths are closely related to “smoking”, and 80% of lung cancer is caused by long-term smoking. Most of the measures and recommendations on how to prevent cancer are aimed at the general population, but there is a group of people who are more likely to develop a certain type of cancer than others, which we call “high-risk group”, that is, people who are at high risk of developing a certain type of cancer. Generally speaking, the more risk factors you have, the more likely you are to develop cancer. In general, the more risk factors you have, the more likely you are to develop cancer. For people with high risk factors, besides taking the same cancer prevention measures as the general population, such as quitting smoking and limiting alcohol, changing bad lifestyles, etc., you should also take more proactive and targeted cancer prevention measures than the general population, such as more proactive removal of these risk factors, closer cancer prevention medical screening, chemical intervention if necessary, and even consider preventive surgery in individual cases if necessary. Preventive surgery can be considered in some cases. Risk factors for breast cancer include family history of breast cancer, specific genetic mutation of BRCA1/2 gene, history of breast cancer on one side, high risk of breast cancer on the opposite side, previous history of radiation therapy to the chest wall, exposure to high estrogen environment (young age of menarche, late menopause, never married or childless for life, age of first full-term birth > 30 years, etc.), never breastfeeding or short duration of breastfeeding (total duration of breastfeeding is negatively correlated with the risk of breast cancer). The risk of breast cancer is negatively correlated with the total duration of breastfeeding), excessive intake of exogenous estrogen (estrogen replacement therapy during menopause or estrogen for so-called cosmetic purposes), high-fat and high-energy diet, obesity and overweight, and severe cystic hyperplasia of the breast. High risk factors for esophageal cancer People over 40 years old in areas with high incidence of esophageal cancer, poor dietary habits (excessive intake of pickled products, preference for hot food, hot tea, high salt diet, rough food, fast eating), smoking, alcohol consumption, nutritional deficiencies or inadequacies (vitamin and trace element deficiencies, molybdenum deficiency, zinc deficiency, etc.), family history (there is a family gathering phenomenon of esophageal cancer, which may be due to genetic susceptibility or prolonged exposure of family members to the same environmental carcinogenic factors), family history of esophageal cancer. (family history of esophageal cancer may be due to genetic predisposition or prolonged exposure of family members to the same environmental carcinogenic factors), precancerous lesions of the esophagus (chronic inflammation of the esophagus, esophageal reflux disease, esophageal cardia, esophageal scar stenosis, esophageal leukoplakia, etc.). High risk factors of gastric cancer Bad eating habits (irregular diet, too fast and too full diet, overeating, etc.), unclean diet, preference for smoked and fried foods, long-term high-salt diet and salted and smoked foods (such as pickled fish and salted vegetables), frequent consumption of overnight or spoiled moldy foods, preference for red meat, low intake of fresh vegetables and fruits, nutritional imbalance or deficiency, smoking and alcohol abuse, family history of gastric cancer, chronic atrophic gastritis, chronic gastric ulcer, chronic gastric polyposis, chronic gastric ulcer, chronic gastric ulcer and gastric polyposis. chronic gastric ulcer, gastric polyp or stomach surgery, H. pylori infection. Risk factors for liver cancer Age over 40 years (can be extended to over 45 years for women), smoking, long-term alcohol consumption, hepatitis B virus carriers, history of chronic viral infection (hepatitis B or C), cirrhosis, micronutrient deficiencies (low selenium, molybdenum, manganese, zinc and high iron, nickel, arsenic), contaminated drinking water. Risk factors for colorectal cancer High animal protein, high fat and low fiber diet, constipation, sedentary physical activity, obesity, smoking, long-term alcohol consumption, micronutrient deficiencies (molybdenum, calcium, selenium), chronic ulcerative colitis, familial colonic polyposis, colonic adenoma syndrome. Risk factors for pancreatic cancer: middle-aged or older, long-term smoking, alcoholism, high-fat, high-protein, high-calorie diet, chronic pancreatitis. Risk factors for lung cancer Smoking (especially those who start smoking under 20 years old, those who have been smoking for more than 20 years, those who smoke more than 20 cigarettes per day), second-hand smoke, occupational exposure to asbestos, arsenic, uranium, nickel, chromium, etc., air pollution from interior decoration materials, long-term exposure to kitchen fumes, and severe environmental pollution in the place of living. Risk factors for ovarian cancer Early age at menarche, delayed age at menopause, infertility or low number of pregnancies, long-term use of ovulation-promoting drugs, exogenous estrogen intake (long-term use of estrogen replacement therapy after menopause), high-fat diet, obesity and overweight, family history of ovarian cancer, hereditary ovarian cancer syndrome. High-risk factors for cervical cancer Early sexual debut, disordered sexual behavior, too many sexual partners, promiscuous sex, early marriage, early age at first birth, multiple births, husband’s extramarital sex, husband’s penile cancer, husband’s or sexual partner’s penile circumcision, chronic inflammation of the cervix and vagina, cervical human papillomavirus (HPV) infection, and smoking. Risk factors for endometrial cancer Infertility or infertility, early menarche or delayed menopause, exogenous estrogen intake (long-term estrogen replacement therapy after menopause), long-term use of triamcinolone (postoperative adjuvant therapy for breast cancer), nutritional excess overweight, obesity, high-protein, high-fat, high-sugar diet, history of pelvic radiation, family history of ovarian cancer, history of endometrial hyperplasia, history of polycystic ovary syndrome. Risk factors for bladder cancer Long-term exposure to dyes, rubber and plastic products, paints, leather, detergents, pesticides, etc., long-term smoking, chronic urinary tract infections, chronic cystitis, long-term residual urine and foreign body irritation (indwelling catheter, bladder stones), habit of holding urine, long-term urethral obstruction, history of pelvic radiotherapy, long-term excessive coffee consumption, long-term use of hair dyes. Risk factors for kidney cancer Over middle age, smoking, alcohol abuse, obesity, hypertension, diabetes, high intake of dairy products, low intake of vegetables and fruits in the diet, insufficient intake of vitamin A, occupational exposure to long-term exposure to cadmium, coke, etc., family history of kidney cancer. High-risk factors for prostate cancer Older men over 50 years old, especially over 70 years old, early marriage, too frequent sex life in early years, sudden reduction in sex life or stopping sex life too long and too early in old age, excessive intake of meat, especially red meat, and less intake of fresh vegetables and fruits, fondness for food cooked with coffee, ginger, pepper and other spices, fondness for salt, and hypertrophy of prostate gland. High-risk factors only mean a higher risk of cancer, but it does not mean that if you have these high-risk factors, you will definitely get cancer, there is no need to panic, but because you have a higher risk of cancer than others, you should pay more attention and be more vigilant, you should do a good job of cancer prevention measures, stay away from cancer-causing factors, you should do a good job of medical examination and screening, and not having these high-risk factors does not mean that you will not get cancer, it does not mean that you can rest easy, you should also do a good job of cancer prevention measures, you should also do regular examination and screening. We also need to take good cancer prevention measures and have regular checkups and screenings.