Even though nipple discharge is most often caused by a benign disease, it can rarely be a sign of breast cancer. Nipple discharge may occur spontaneously / on squeezing, from one / both breasts, from one / more than one duct. In addition, accompanying factors such as its relationship with menstruation / pregnancy / exercise, history of trauma, medication use and hormonal disorders should be evaluated.
Suspicious nipple discharge usually occurs spontaneously and comes from one breast and a single duct. A lump may or may not accompany it, and the discharge may be clear or bloody. It is also more worrying after the age of 50.
Physiological nipple discharge usually occurs on squeezing and comes from both breasts and from more than one duct. It may be clear in adolescence, bloody in the last period of pregnancy and at the beginning of breastfeeding, dark-colored in those who have used birth control pills for a long time, and a dirty cloudy discharge before menopause.
A detailed history, breast examination and radiological tests are recommended for every woman with nipple discharge. A smear of the nipple discharge must be made and evaluated cytologically. Ultrasound, mammography and, when necessary, breast MRI can help with the presence of a solid or cystic mass, intraductal papilloma or ductal ectasia. The use of ductography or ductoscopy is controversial and depends on the breast surgeon and the radiologist.
Even though nipple discharge is mostly caused by a benign disease, the presence of bloody or clear discharge in particular should suggest breast cancer. The causes of bloody discharge are 45% intraductal papilloma, 30-35% ductal ectasia, 8-15% carcinoma and 5-10% infection. Yellow, green, brown or gray discharge is usually associated with fibrocystic changes. Green cloudy discharge is due to ductal ectasia or duct blockage. In the presence of a prolactinoma, there is typically milky or light-colored nipple discharge from both breasts.
