Dear Jean, It's difficult to say what this might be without further evaluation. As this has been of concern to you now for 4 weeks and has not gotten better, you may want to have your doctor take a look at it and make an assessment.
If you're asking is this a symptom of breast cancer, scaling of the nipple can be a symptom of Paget's disease, a form of localized nipple cancer. This is a very rare disease.
I'm in the process of finding a new gyno and once I do, I'm going to have it looked at. I have a skin condition in my ear so I'm thinking the two are related.
At one point, I was convinced I had Paget's Disease or some other form of breast cancer.