Hi,
I am sorry to hear about your mom's cancer diagnosis.
As much as we would like to help, we in this Forum, are not medical doctors,therefore it's hard for us to explain or understand in details the findings on mammogram results.
The report should be explained in details by your mother's doctor.In the meantime you could post in the "Radiology Community" to obtain the information you are seeking.
Please click on the link below to reach that community, and I hope that you'll get some help with your questions.
http://www.medhelp.org/forums/Radiology-/show/905
Best wishes to both you and your Mother.