Fibroadenoma of the breast is the most common type of tumor in young women. It arises from an abnormally high sensitivity of fibroblasts in the lobules to estrogen, which may be related to abnormalities in the quantity or quality of estrogen receptors contained in the fibroblasts. Estrogen is the stimulating factor for the development of this disease, so fibroadenoma occurs during the functional phase of the ovary. Clinical manifestations: This disease is a common breast tumor in women, and the high incidence age is 20-25 years old, followed by 15-20 years old and 25-30 years old. It occurs in the upper outer quadrant of the breast, and about 75% of them are solitary, while a few are multiple. Except for the lump, the patient often has no obvious conscious symptoms. The lump increases slowly, resembles the elasticity of a hard rubber ball, has a smooth surface, and is easy to push. The menstrual cycle has no effect on the size of the mass. Surgical excision is the only effective treatment for fibroadenoma. Since pregnancy can increase the size of fibroadenoma, fibroadenoma found before or after pregnancy should generally be removed surgically. The tumor should be removed in its entirety with its envelope, with a small amount of normal breast tissue wrapped around it, and the mass must be routinely examined pathologically.