Ductal carcinoma of breast is a pathological type of breast cancer, which can be divided into ductal carcinoma in situ and invasive ductal carcinoma according to histologic pattern. 1. Ductal carcinoma in situ: pathologically, the ducts of this type of breast cancer have the obvious feature of expansion, the cancer cells are in the expanded ducts, and the basement membrane of the ducts is still relatively intact, and this type is the more common type of breast cancer. 2. Invasive ductal carcinoma: this type of breast cancer is developed from intraductal carcinoma, in which the cancer cells have broken through the basement membrane of the ducts and are ready to infiltrate into the interstitium, and the cancer cells are arranged into nests with a small amount of adenoid structure, which is the most common type of breast cancer. If patients have breast discomfort symptoms, it is recommended to go to breast surgery in time, and under the guidance of professional doctors for standardized consultation to control the development of the disease in time.