The screening age for breast cancer is recommended by international organizations to be 20-40 years old, with clinical physical examination at least once every three years and annual mammogram screening for women over 40 years old. Screening for both cancers in Beijing also starts at the age of 20. For young women under 35 years old, ultrasound is recommended as the main screening test, and for women over 40 years old, a combination of ultrasound and mammogram is recommended. Once a breast nodule or breast lump is detected during the screening, it is necessary to visit a breast specialist clinic to see if further treatment is needed. In addition, it is also important to pay attention to the timing of screening, usually 7-14 days after menstruation. It is also important to choose the screening means according to the high incidence of breast cancer and family history.