The most common age of breast cancer is between 45-55 years old, so it is recommended that women over 40 years old should go to the hospital for regular checkups or perform self-examinations at home, and if a lump or mass is found in the breast, they should go to the hospital immediately. For patients who do not have breast lumps, ultrasound or mammography can also be performed during regular checkups at the hospital, because ultrasound or mammography has a very high diagnostic rate for small breast lumps, and it is possible that the doctor may not be able to touch the lump in the patient’s breast during physical examination, but ultrasound or mammography can detect a lump in the breast, usually for smaller lumps. The diagnosis rate is higher for smaller masses. If the lump is found to be malignant during ultrasound or mammography, further examination is needed.