Although it is not too commen, it does occur. It is a great thing that she got it checked out. I do have to say, that the doctor giving her a card for a surgeon does not indicate anything. My 27 yo SIL found a lump 2 weeks ago, did the mammogram and ultrasound, and rather than a needle biopsy, they are going to do surgery to extract and test. So, there is a good chance that is what it is for.
(((Hugs to you and dd)))
They are doing surgery because needle biopsy's do not get all the info that the dr. needs, and the tissue could be too dense to get an accurate sample..