Dilated and swollen breast ducts on the right side of breast enlargement may be associated with a variety of diseases such as benign breast nodules, intraductal papillomas, and breast hyperplasia. 1. Benign breast nodules: Breast infection or injury may induce breast nodules, which compress the milk ducts, thus causing localized ductal dilatation. 2.. Intraductal papilloma: Bad living habits, dietary habits, drug stimulation, etc. may induce intraductal papilloma, due to the growth of the tumor compression of the proximal mammary ducts, resulting in distal dilatation. 3. Breast hyperplasia: mainly related to endocrine disorders, breast hyperplasia will compress the local breast ducts, and when the ducts are unable to secrete mucus, it will form localized ductal dilatation of the breast. If you have symptoms of localized ductal dilatation on the right side of the breast, it is recommended that you go to the hospital in time to find out the cause of the disease and treat the symptoms.