Hi crash, glad you posted. It's why we're here.
I am currently going through this with a friend as well. She's got other things going on, too (isn't that always the way?) and I wasn't expecting the call that this was happening to her in addition to all the other things she's dealing with. Geez.
Anyway, it's good they're being so careful, as you know. Do you have yearly MRIs? Did they find this on MRI or did you find a lump? MRIs are great but they do have a high rate of false positive, which they then are obligated to investigate. If it does turn out to be something, it sounds like they caught it very early (the whole purpose of MRIs, as they reassure me every year as I'm practically shaking going into the machine

) and that's always reassuring.
We'll be here with you while you wait. I am a "teller", I am not very good at keeping things to myself when something's bothering me (which is both a blessing and a curse, which you'd probably appreciate more if you knew me IRL

My friends, family and coworkers could tell you good stories I'm sure, lol). Think of how you would feel if it was your family member - would you want to know? Give them a chance to support you now.