Unilateral uniforaminal overflow is not cancerous, it belongs to the category of tumor and is usually benign. Unilateral uniforaminal overflow is a common clinical symptom of intraductal papilloma, about 70% of which occurs in the jugular abdomen of the large milk ducts near the nipple. Due to the compression of the tumor on the surrounding tissues and blood vessels, a small amount of blood or tissue fluid leaks out, which leads to a small amount of fluid overflow from the milk ducts. Usually the tumor is very small and is supplied by small blood vessels in the surrounding area. It is poorly demarcated from the surrounding tissues and is not clearly visible, while larger tumors may be palpable under the skin around the areola. The reason for clinical consultation is mostly nipple overflow, which may be bloody, brownish-yellow fluid, and small in amount. Intraductal papillomas are usually benign, with a malignant rate of less than 6%. For those who are older, have active endothelial hyperplasia, and have a family history of breast cancer, the likelihood of malignant transformation is higher, and it needs to be taken seriously.