Breast cancer is a malignant disease in itself and there is no such thing as a benign disease. However, breast cancer does have many stages. According to international standards, there are TNM stages, which usually classify breast cancer into stage 0, stage I, stage II and stage III, according to the degree of malignancy, size, lymph node metastasis status and systemic condition. Benign usually refers to benign breast masses, which are not the same thing as malignant masses at all. A benign breast mass is usually a breast nodule on ultrasound or palpation, and a grade III or IV breast nodule is reported on surgery or examination, and pathology after surgery indicates benign, usually including fibroadenoma, intraductal papilloma, etc. Benign ones such as fibroids are very unlikely to become cancerous and can be almost ignored. Although intraductal papillomas are also benign, they have a probability of malignancy and require surgery. If intraductal papilloma is not removed surgically, there is a 7%-28% chance that it will become cancerous according to foreign reports. Therefore, first of all, it is clear that breast cancer is not a benign mass, but some benign masses, such as fibroadenoma and intraductal papilloma, must be explained by a specialist whether they will become cancerous in the future.