Breast nodules with clear borders are mostly considered to be related to benign diseases such as cystic hyperplasia of the breast, fibroadenoma of the breast, and lipoma of the breast. 1. Breast cystic hyperplasia: the nodules formed by breast hyperplasia are hard, with clear and movable borders, and may be accompanied by breast pain, nipple discharge and other symptoms, which are mostly related to endocrine disorders of patients. 2. Breast fibroadenoma: mainly related to the abnormal sensitivity of breast fibroblasts to estrogen, it can be manifested as painless and movable breast lumps and nodules with clear boundaries, which can be cured by surgical excision and may recur. 3. Breast lipoma: mostly located in the fat layer, manifested as round or oval shape with clear boundary, the main treatment method is surgical excision. The main treatment method is surgical excision. When breast nodules appear, you should consult the doctor in time for puncture biopsy to determine the nature of the nodules, and then treat them positively after clarifying the cause of the disease, so as to avoid delaying the condition.