We are no longer strangers to breast adenocarcinoma. It is a malignant tumor that occurs in the glandular epithelial tissue of the breast. Breast cancer occurs in 99% of women and only 1% of men. Nowadays, breast cancer has become a common tumor that threatens women’s physical and mental health. Early detection of breast cancer is not easy to attract attention as it does not have typical symptoms and signs. Breast lumps 80% of breast cancer patients are first diagnosed with breast lumps. Most breast cancers are painless lumps, only a few are accompanied by varying degrees of hidden pain or stabbing pain. Nipple overflow: blood, plasma, milk or pus flowing from the nipple during non-pregnancy period, or milk still flowing even after stopping breastfeeding for more than half a year, is called nipple overflow. If it is accompanied by breast lumps, it should be further examined. The most common one is the “dimple sign”, which means a small dimple in the breast skin, like a small dimple. If the cancer cells block the lymphatic ducts, “orange peel-like changes” will appear, which means the skin of the breast will have many small dots and depressions, just like an orange peel. 4.Abnormality of nipple and areola If the tumor is located in or close to the deep part of nipple, it may cause nipple retraction. If the tumor is far away from the nipple and the large ducts in the breast are invaded and shortened, it may also cause nipple retraction or elevation. 5. Axillary lymph node swelling More than 1/3 of breast cancer patients admitted to most hospitals have axillary lymph node metastasis. The swollen lymph nodes are hard, scattered and pushable. High risk groups 1. The incidence of breast cancer usually rises gradually after the age of 25, reaches a peak in the age group of 50-54, and gradually decreases after the age of 55; 2. Family history of breast cancer is a risk factor for the occurrence of breast cancer; 3. 7. Atypical hyperplasia of the breast; 8. High dose of radiation to the breast; 9. Long-term use of exogenous estrogen; 10. Post-menopausal obesity; 11. Long-term excessive alcohol consumption; 12. Self-examination 1. Observe whether the skin is ulcerated or sunken, and whether there is discharge from the nipples from all angles, such as front and side. 2.Raise your hands up and observe whether there are indentations in your breasts. And observe the shape of the breasts from all angles, including front and side. 3.Use three fingers other than the thumb and little finger to caress the breasts in a wide range. You can think of the breast as the sun, with the fingers moving in the manner of the earth’s rotation and revolution. 4.In addition to the rotation and revolution method, you can also use a horizontal direction to examine the breasts by stroking them from the outside to the inside. 5. Put your right hand down and reach into your armpit with your left hand to see if you can feel the lymph nodes. Grasp the nipple and check if there is any discharge. (The 9th to 11th day after menstruation is the best time for mammography).