Sometimes women will develop a discharge which can be brown or black and not be dangerous and is hormone related. It sometimes has to do with menopause.
However, only your doctor can tell you for sure.
Hi as to your question: My breast are leaking a brown sticky discharge should I be concerned.My answer yes,it is not normal to have a colored discharge coming from your breast.Have you recently gave birth?You should see your gynecologist.Take Care TNT406.