I have some patches on the skin between breasts. first I got it about 2 years ago, it was little spot, pinkish and little itchy. It grew slowly but became light brown. Since than it s being growing. Old patches stay brown and doesn t itch, but as it moves over my breasts, new pink spots are itchy until they become brown too. until now I had between breasts, within a week they moved on my breast. What it can be?