Breast discharge is the spontaneous flow of fluid from the nipple at any time other than during nursing. Breast discharge can be caused by a wide range of disorders, including breast cancer, breast ectasia, and breast infection. Sometimes it's possible to feel breast cancer as a breast lump. The breast lump may or may not be painful or tender. Breast duct malformation (duct ectasia) can lead to breast discharge. Mastitis is the medical term for a breast infection, and mastodynia is the medical term for breast pain. Another name for the nipple is areola. A physician should evaluate persisting breast discharge (nipple discharge).