It is a disorder of the normal structure of the breast caused by physiological hyperplasia and incomplete restoration. In China, cystic changes are rare, and glandular hyperplasia is the main cause, so it is mostly called “mastopexy”. The World Health Organization (WHO) collectively calls it “benign breast dysplasia”. The risk of malignancy is two to four times higher than that of normal women, and the clinical symptoms and signs are sometimes confused with those of breast cancer. Etiology The cause of this disease is not well understood. Currently, it is thought to be related to endocrine disorders and psychological factors. The decrease of luteinizing hormone secretion and the relative increase of estrogen are the important causes of this disease. It is mainly a benign hyperplasia of the interstitial mammary glands, which can occur around the ducts and be accompanied by cysts of various sizes; it can also occur in the ducts and manifest as papillary hyperplasia of the epithelium, accompanied by cystic dilatation of the milk ducts. In addition, there is a type of lobular parenchymal hyperplasia. Symptoms The prominent manifestations are breast swelling and pain and intramammary lumps. I. Breast swelling and pain: It is common to have unilateral or bilateral breast swelling and pain or tenderness. The duration of the disease varies from 2 months to several years, and most patients are characterized by cyclic pain, which occurs or worsens in the premenstrual period and decreases or disappears after menstruation. It must be noted that although the cyclical nature of breast pain is typical of the disease, the lack of this feature does not negate the existence of the lesion. Breast lumps: they are often multiple, unilateral or bilateral, mostly in the upper outer quadrant; and their size and texture often change periodically with menstruation. On examination, the lump can be palpated as a nodal structure, varying in size, with unclear boundaries with the surrounding tissues, mostly with tenderness, without adhesions to the skin and deep tissues, and can be pushed, and the axillary lymph nodes are not enlarged. In addition, there is also a long course of disease, slow development, and sometimes nipple overflow and other manifestations. The nodules in the breast are essentially large and small cystic dilated milk ducts, and the nipple discharge comes from these cysts and is yellow-green, brown or bloody, or occasionally colorless plasma. Examination Based on the above clinical manifestations and signs, it is not difficult to diagnose this disease. However, it should be noted that malignancy can occur in a small number of patients (about 2-3%), therefore, it is important to follow up and observe the suspected patients, usually every three months. Unilateral and limited lesions should be especially vigilant. Treatment Since the mechanism and cause of the disease are not precisely understood, the current treatment is basically symptomatic. Some patients often resolve on their own after a few months to 1 to 2 years after the onset of the disease and do not require treatment. For patients with more obvious symptoms and extensive lesions, a bra can be used to support the breast; oral administration of Xiaojin Dan or Xiao Yao San, or 5% potassium iodide can relieve the symptoms. In recent years, there are more similar drug products, such as breast lump elimination, breast fetish elimination, asparagine tablets, flat elimination tablets, sac fetish spirit, triamcinolone, etc., with different treatment effects. In addition, there are still hormone therapy, some people use androgens to treat this disease, in order to inhibit the effect of estrogen, soften the nodules and reduce the symptoms; however, this treatment may aggravate the imbalance between human hormones, and should not be routinely applied. It should only be considered when the symptoms are severe and affect normal work and life. In the follow-up observation of patients, once a lump with rapid growth or hardening texture within a short period of time is found, the possibility of cancer should be highly suspected, and if necessary, a biopsy or simple excision of the affected breast should be performed, and if cancer cells are found in the frozen section during surgery, it should be treated as breast cancer.