I am a 43-year-old female. Following a very itchy spell and redness, I develop about three red spots in my breast cleavage (the spots/bumps are no more than an eighth of an inch in diameter at most) that later turn to brown (raised spots) and then flake off. A few days to a week later, the cycle starts again. My dermatologist says these are nothing to worry about, but I am not convinced. What is the cause of this? Thank you.