Breast Screening Target: All women ≥20 years of age, except those with serious contraindications or without appropriate treatment. The census population is divided into two groups based on the presence of chest radiotherapy, history of pathologically confirmed lobular carcinoma in situ (LCIS) or atypical hyperplasia, and associated genetic abnormalities. 1. Routine screening if there is no history of the above diseases If at the age of 20-39 years, only: clinical examination every 1-3 years; monthly self-examination is recommended; if the Gail model (age at menarche, age at first birth, number of breast biopsies, history of biopsy-confirmed LCIS or atypical hyperplasia, and number of first-degree relatives who have had breast cancer) labeled with a 5-year risk of breast cancer >1.7% of the Women with a 5-year risk of breast cancer >1.7% as standardized by the Gail model, then annual mammography from age 35 years; if ≥40 years, screening includes: annual clinical examination; annual mammography; monthly self-examination is recommended; and if the 5-year risk of breast cancer as standardized by the Gail model is >1.7%, then annual risk-reduction assessment is performed; 2. If a woman has had a history of radiation therapy to the chest in her 20s or 30s, then in her 30s, only: annual screening is required. At less than 30 years of age, only: an annual clinical examination is required; monthly self-examination is recommended. If over 30 years of age, screening should include: clinical examination every 6 months; annual molybdenum-palladium radiographs are recommended; and monthly self-examination is recommended from the 10th year after radiotherapy. 3. Women with genetic testing or genetic risk assessment identifying genetic abnormalities such as BRCA1(3), under 30 years of age, should only require: annual clinical examination; monthly self-examination is recommended. If over 30 years of age, screening should include. Include: clinical examination every 6 months for 5 to 10 years prior to discovery and annual molybdenum-palladium radiography; monthly self-examination is recommended. 4, If there has been previous pathologically confirmed LCIS or atypical hyperplasia in a woman, then: clinical examination every year since the diagnosis has been clarified and molybdenum-palladium radiography every year are recommended. If there are no abnormal findings through these censuses, then follow-up remains according to this rule.