Small nodules in the breast can be considered for a variety of reasons, but are usually not particularly problematic. For example, cystic hyperplasia of the breast can also cause breast nodules, but sometimes they are accompanied by clinical symptoms, such as breast swelling and pain, which is especially pronounced before menstruation and relieved after menstruation, and the nodules are multiple. Fibroadenoma is a nodule in the breast that can be detected on examination or ultrasound, but the surface of the nodule is smooth, mobile and has no obvious symptoms. Breast cysts show no echogenicity on ultrasound, no obvious uncomfortable symptoms, and nodules and lumps in the breast on physical examination. Of course, the most worrying is breast tumor, especially breast cancer, which is usually a painless lump with bad activity and hard surface, and can be clearly identified by ultrasound.