What is the most common etiology for bloody nipple discharge?
Benign solitary papillomas are the most common etiology of bloody nipple discharge. Solitary papillomas arise within the ducts close to the nipple and are benign tumors composed of glandular and fibrous elements. Solitary papillomas do not increase a woman’s risk for breast cancer.
Papillomatosis is a condition in which there are multiple papillomas arising in the peripheral ducts. Papillomatosis typically does not cause nipple discharge. There is an increased risk of breast cancer associated with papillomatosis.