Ductal disease should be intraductal lesions of the breast, which may generally be caused by breast cysts, bad lifestyle habits, breast cancer and so on. 1. Breast cyst: Breast cyst refers to a cystic mass in the chest, which is usually caused by endocrine disorders, and may have symptoms such as breast pain, breast lumps, etc., which in turn affects the breast ducts and develops lesions. 2. Bad life habits: due to long-term consumption of high-fat food, frequent drinking and smoking, long-term use of contraceptive pills, etc., which cause estrogen to increase, thus causing ductal lesions. 3. Breast cancer: Breast cancer is a kind of malignant tumor, which is usually caused by endocrine disorders and various carcinogenic factors of the patients, and may have symptoms such as abnormal areola, fatigue, enlarged axillary lymph nodes, etc. When it violates the ducts of mammary glands, relevant lesions will appear. In addition, diseases such as mastitis and breast trauma may also lead to breast ductal lesions. It is recommended that patients find ductal lesions and go to the hospital for timely examination and symptomatic treatment under the guidance of the doctor.