Breast cancer is one of the most common malignant tumors in women, with about 200,000 new cases and 40,000 deaths in China. In Shanghai, Beijing and other major cities, the incidence of breast cancer has ranked first among female malignant tumors. In the United States, breast cancer accounts for 30% of female malignant tumors, ranking first, and is the second cause of cancer death after lung cancer. The incidence of breast cancer is often related to heredity, and the incidence is higher in women between 40-60 years old, before and after menopause, and it is one of the most common malignant tumors that seriously affects women’s physical and mental health and even threatens their lives. The causes and risk factors of breast cancer: 1. Changes in lifestyle and improvement in nutritional status 2. Early age of menarche and delayed age of menopause. 3. Decrease in childbirth and breastfeeding. 4. Endocrine disorders. 5.Environmental factors, ionizing radiation. 6.Family genetic factors.