The causes of breast lumps are breast fibroadenoma, breast cyst, breast cystic hyperplasia, and breast cancer, as follows: 1. Breast fibroadenoma: the lumps are smooth to the touch, rounded or rounded, with good mobility, and can be diagnosed by ultrasound, and the treatment is surgical excision; 2. Breast cysts: some of them are soft to the touch with clear borders, and can be diagnosed by ultrasound; 3. Breast cystic hyperplasia: the pain and discomfort in the breast accompanied by the menstrual cycle, and the symptoms are relieved after menstruation, and can be treated with medication after diagnosis; 4. Along with the menstrual cycle of breast pain and discomfort, after the onset of menstruation symptoms are relieved, after diagnosis can be symptomatic drug treatment; 4, breast cancer: manifested as painless breast nodules, touching the edge of the unclear, irregular, poor mobility, rapid growth, but also need to be diagnosed by ultrasound examination. Breast found a lump, need to go to the regular hospital in time, do ultrasound examination, determine the specific circumstances of the lump, and then guide the formal treatment.