When it comes to dealing with cancer, you are your own best advocate. Your mom should educate herself about the subject. How do they know she has BC?? Did they do a biopsy?? Has she had any surgery?? Sometimes they do try to shrink the tumor before surgery if anticipating doing a lumpectomy but also in doing this they must obtain clear margins all around the tumor or mastectomy is in order but your mom should be aware of her choices of treatment. If her doctors are of the nature that they feel they know what is best rather than discuss it with your mom, it is time for her to find another doctor who will take her feelings and considerations into account. She is lucky to have you as her advocate.