Almost the majority of mastectomies in clinical practice are due to the development of malignant tumors in the breast, such as breast cancer. The exact cause of breast cancer is not clear. It is the most common malignant tumor of the breast in women, and the cause of its development is currently believed to be significantly related to the menstrual cycle, early menarche, late menopause, and the consumption of overly oily, spicy, and stimulating foods, as well as the fact that breast cancer has a certain family genetic susceptibility. For breast cancer, early detection, early diagnosis and early treatment are advocated. The typical clinical manifestation of breast cancer is a painless hard lump with poor mobility and unclear boundary. In the absence of distant metastasis, i.e. not advanced breast cancer, the preferred treatment is modified radical or radical excision, together with postoperative comprehensive treatment, including chemotherapy, radiotherapy and even molecular targeted drug therapy, The lymph nodes in the axilla are usually removed.