I have had this condition for about 6 years. It subsides completely sometimes that I think it's gone, but then it always comes back maybe once a year. It always starts as fresh, red, itchy bumps under my breasts and on the belly area. The red bumps do pretty quickly go away and become dark brown spots, but there are always more red bumps coming up.
The red bumps in the picture are the new bumps, and the dark brown/scabby parts are no more than 3 weeks old.