Para-mammary is an abnormal development where the mammary glands have disappeared completely. 2. There are nipples without mammary tissue. 3. There are nipples and breast tissue. Parametrium is a common breast development deformity in women. It is often an underdeveloped tissue, most of which resembles a baby’s breast, or only a little skin pigmentation is seen, and there may be a little skin thickening in the center, similar to a small nipple. Some have only mammary glands, some have only nipples, but there are also complete breast bodies (nipples, areolas, glands) visible in the axillae. The areola and glands are larger. The parametrium is also swollen and painful before menstruation, and increases significantly during pregnancy, and even produces milk during breastfeeding. There are different opinions on whether and when surgery is appropriate for parametrial breast. Some people believe that they do not need to be treated, while others advocate removal. It is generally believed that asymptomatic and soft parametrial breasts can be reviewed regularly without immediate surgical treatment. For those with the following manifestations, surgery should be performed: 1. The parametrium is a multiple breast deformity that affects the appearance; for larger anterior axillary parametrium that affects the aesthetics and dress, and the patient has an urgent need for surgery, surgery can be performed. 2.If there are obvious hard nodules, parametrial fibroids, nipple overflow, obvious swelling and pain of the lump, or if there is a certain possibility of malignant change, or if the lump has increased significantly recently, surgery can be considered. 3.Significant pain symptoms; pain symptoms affect the patient’s life; 4.Surgery should be performed for those with parametrial fibroids or nipple overflow. 5.If the diagnosis is unclear and other tumors cannot be excluded. Surgical methods: 1.Under continuous epidural anesthesia or intravenous anesthesia, only a few of them are performed under local anesthesia. Local anesthesia is not conducive to the freeing of the flap by electric knife, nor is it conducive to the differentiation of fat and parametrial glandular tissue. 2, the choice of incision should be considered beautiful and concealed. For anterior axillary parametrium, the oblique shuttle-shaped incision at the lateral edge of the pectoralis major muscle is chosen so that the surgical scar cannot be seen when the patient wears an undershirt after surgery and the tension of the incision is smaller when the affected upper limb is active, which is conducive to the healing of the incision and upper limb activity. After complete excision, a rubber drainage tube and negative pressure suction were placed on the wound surface. The extubation time is after 72h. 3. If the parametrium has no envelope, the flap should be free to the edge of the mass during surgery, and the resection area should be sufficient to ensure the effect of surgical treatment. The entire parametrial tissue should be removed to prevent recurrence. The anterior axillary parametrium should be excised to the outer edge of the pectoralis major fascia, and the bottom should reach the deep subcutaneous fascia. The axillary parametrium should be removed to the front of the pectoralis major muscle and to the posterior edge of the axilla, and the bottom of the parametrium should reach the deep subcutaneous fascia. 4.For the treatment of parametrial cancer, the resection range should be at least 5cm from the edge of the lump, and the muscle tissue should be removed at the same time, and the lymph nodes of the same side of the axilla should be cleared. 5. Rubber drains and negative pressure absorption are placed on the traumatic surface to facilitate the growth of the skin flap. If the tube is removed too early, subcutaneous fluid and blood will accumulate. Postoperative pathology: Pathological examination revealed that lobular hyperplasia occurred in 4.34%, ductal epithelial hyperplasia in 13.04%, and fibroid formation in 7.61%, and it was also reported in the literature that parametrium could be malignant.