What Causes Dry Patch Of Skin Leading To Itchiness On Areola?

I ve had this dry patch of skin on my areola for about 2 - 3 months now. At first I thought it was a rash or just dry skin that would eventually go away. But over the time it s gotten bigger. It s the size of a dime now, before it was the size of a pea. It s so embarrassingly itchy and at times unbearable. I did go to my doctor and got a mammogram, luckily no cancer. I m not sure what this could be. I ve tried anti-itching creams but to no avail. Any idea to what this can be?