Ductal carcinoma in situ (DCIS), also known as intraductal carcinoma, is a pre-cancerous or non-invasive cancerous lesion of the breast.[1][2] DCIS is classified as Stage 0.[3] It rarely produces symptoms or a breast lump that can be felt, typically being detected through screening mammography.[4][5] It has been diagnosed in a significant percentage of men (see male breast cancer).[6]

Reference
Wiki: Breast invasive ductal carcinoma