Intraductal papilloma is a benign papilloma that occurs in the epithelium of the breast ducts and can occur in women of any age after puberty, but is more common in menstruating women, especially in women aged 40 to 50 years. As a common benign breast tumor, the main clinical manifestation of intraductal papilloma is nipple discharge, which may occur when the breast is squeezed, but is more likely to be spontaneous. The overflow may be continuous or intermittent. The majority of patients present to the hospital with a complaint of nipple discharge. The color of the overflow is related to the length of time it remains in the milk ducts after bleeding – the longer it remains in the ducts after bleeding, the more soy-like the color of the overflow is; if it overflows out of the milk holes immediately after bleeding, the color is bright red; and if there is little bleeding and other overflow, the color is The color is lighter. The amount of blood spilled is related to the extent and depth of the lesion in the duct. Sometimes the overflow is bloody, sometimes mucus, sometimes more, sometimes less, or even no overflow at all. Patients often seek medical attention by chance when they find blood in their undergarments or bras. Most cases are not associated with pain. In a few cases, when the tumor is large and obstructs the breast ducts, it can produce pain and lumps, which will become smaller and the pain will be relieved to varying degrees as the accumulated blood and fluid is drained. Since the tumor of intraductal papilloma is very small, it cannot be palpated in most cases, and only about 20% of patients can find the lump at the nipple areola. The masses are nodular or striated, soft, and generally small, with a diameter of 0.5 to 1 cm, or occasionally more than 2 cm, and when gently pressed, bloody or coffee-like fluid can escape from the nipple. The characteristic manifestations of intraductal papilloma are three: one is nipple discharge, especially bloody discharge; the other is pain, which is relieved by the discharge of the accumulated blood and fluid; and the third is a mass, nodular or striated, mostly in the areola area of the nipple. Classification of intraductal papilloma: According to the number of lesions and the location of occurrence, intraductal papilloma can be classified as solitary, i.e., large intraductal papilloma and multiple, and medium and small intraductal papilloma (also known as large ductal papillomatosis, which is a precancerous lesion). Large ductal papillomas originate in the abdominal region of the milk ducts and are mostly solitary and located in the subareolar area, accounting for 75% of all cases; small and medium ductal papillomas originate in the terminal ducts of the breast and are often multiple, located in the peripheral area of the breast, with unclear borders and uneven texture, accounting for 25% of all cases. In general, single large intraductal papillomas are more likely to overflow, while multiple small and medium intraductal papillomas are less likely to overflow. There are different views on whether intraductal papilloma of the breast is carcinogenic or not. Some people have followed up 427 cases of intraductal papilloma for 1-22 years, and only 2 of them were cancerous, so the cancer rate of this disease is considered low; however, others hold a different view – a set of statistics shows that the malignant rate of this disease reaches 5%-10%, so it is called “precancerous lesion”. The rate of malignancy is 5% to 10%, so it is called “precancerous lesion” and has been given sufficient attention. Although there is controversy on the issue of carcinoma in breast ducts, there is one thing that most people agree on, that is, single papilloma in large ducts is rarely malignant (but by no means not carcinoma), because single intraductal papilloma is well differentiated, its origin is independent, not related to papillary carcinoma, and has no tendency to become malignant; while multiple papillomas occurring in the terminal ducts of the breast have active cell proliferation and are prone to malignant. Therefore, it is considered as precancerous lesion. Large ductal papillomas are generally small and ineffective with drug therapy, so surgery is currently effective. The key to the current surgical procedure is precise surgical excision, i.e., excision of the dilated duct + diseased breast segment, and the key is to perform 0.4 ml Melanogram according to the direction of the papillary overflow duct to determine the extent of the dilated duct + diseased breast segment. Therefore, it is recommended that patients should not squeeze the nipple overflow frequently before surgery, so that the scope of the overflow can be found precisely during surgery, and the aesthetic and curative effects can be achieved with a ‘minimally invasive’ surgery under conventional surgery.