A small amount of breast tissue behind the nipple is normal in men. If congenitally more breast tissue is constructed than normal, this may further develop during puberty and become visible. ( Young) men are ashamed of this and it can also be painful . Sometimes the breast tissue develops on one side only.
Breast development in (young) men can be an indication of excessive hormone production somewhere in the body but this is exceptional. However, if this is the case than it is imperative to recognized this prior to treatment. A consultation with an internist or pediatrician can provide clarity. The use of anabolic steroids has to be refrained from.