nipple blisters

I am a 3 yr IDC survior, stage 2, grade 3.  I just noticed two blister like places on the nipple of the non-disease breast.  Any idea of cause...need for concern?  They are not painful nor esp. red..almost darker in color than other areas on the nipple.  Thank you.

[CCF-RN,MSN-rf]

Dear honeybee:  Skin on the breast, like all skin, can get irritations or pimples.  Since it is not itching or causing pain, it is reasonable to keep an eye on it.  If it gets bigger or causes you problems, or if there is no improvement after a week or so, have your doctor take a look.