Hi Mom just diagnosed with Invasive Ductal Cancer

Hi I'm 38. My mom who is almost 65 was sdiagnosed with breast cancer yesterday. I join this site to learn about the disease for her and hopefully get some support of my own. I have five sibling but I am the one that is looked to to be "strong" and support evryone else. I have three children of my own. Two of which sffer from multiple chronic health conditions so as you can see I already have my hands full.

My mom pathology report shows her tumor is grade three which seems to be pretty bad. We dont' know the stage of the disease yet but the doctor suspects it may have spread to her lymph nodes.
I understand most of the patholgy report means but I am having trouble understand a few things. If anyone knows what the following means I would aprpeciate any light you can shed on it.
three cores of breast parenchyma infiltrated by sheets and nests of malignant cells with abundant foamy cytoplasms

Well, I've probably already gone on long enough. Just wanted to introduce myself.

Val