Hi. I am a 51 year old woman, and about 3-4 years ago I noticed a small, (about size of a one penny piece) red mark on my chest, right in between my breasts. Since then, it has grown to around 4 times the size. It is not raised, itchy, scaly or painful. In fact, if I couldn't see it, I would not know it is there. It looks like a birthmark. Any ideas what this could be? All advice gratefully received.