There are many reasons for nipple inversion, specifically the following: 1, congenital nipple inversion, nipple inversion at birth; 2, nipple trauma or surgical scar caused nipple inversion, nipple trauma or surgery during the period of nipple development, leading to the formation of a scar, so that the nipple development is limited or stopped, resulting in nipple volume is small and inverted; 3, mastitis, in the infancy or the period of nipple development, the breast occurred Mastitis, during infancy or nipple development, inflammation of the mammary gland causes nipple development to be hindered, resulting in nipple inversion; 4. Breast cancer, cancer patients have breast pain, nipple inversion, and cellulite changes in the breast. Nipple inversion can be reset by manipulation, or breast pump pulling, or surgery can be used to loosen the shortened ligaments. If the nipple inversion is caused by cancer, it needs surgery to remove the breast, meanwhile, chemotherapy will be carried out after surgery, combined with endocrine therapy and traditional Chinese medicine treatment.