If it is clear or yellow in color, it is generally considered to be caused by breast enlargement or inflammation in the ducts, and needs to be treated with lactoscopic irrigation and oral Chinese medicine. If the fluid is yellow or brown in color, it is considered to have intraductal papillary tumor inside and needs to be examined by lactoscopy for intraductal tumor, and if so, it needs to be removed surgically. If there is bloody fluid, it is considered to be intraductal tumor or intraductal cancer, and further pathological examination is needed. There is also milky fluid coming out of both nipples, in which case CT of the head and female series are needed to rule out pituitary tumors in the head.