Surgery to remove atypical cells

My mother had a biopsy about two months ago and the pathology report notes that the axillary mass( a firm gray white mass 10 cm C/S solid gray white, Under the microscopic result: FibrousFibrous dysplasia stroma infiltrated by atypicalAtypical pneumonia cells forming, papillae, glands, solid sheets. Moderate amount of mitosis seen. Axilla-Moderately differentiated adenocarcinoma. My firstFirst progesterone  
question is, is there any way to conclude that this is breast cancer?  
The doctors had done mamogram (mammogram) (mammogram) and ultrasound but found no cancer in her breast nor in any other organ. Secondly, approximately what stage of breast cancer would be estimated from the pathology report? Is chemo the best option?
Lastly, I taught surgery to remove the lump was the best initial treatment for atypical cells.
Thank you  for your time to answer my questions.

[Kamal S Saini, MD, MRCP (UK), DM]

Hi,
Your mother has been diagnosed with metastatic adenocarcinoma of axilla (with unknown primary) almost 2 months ago.
I hope that in the meantime she has tests (MRI breast, PET CT, ER, PR, and other IHC stains on biopsy specimen, tumor markers, genetic tests, etc) to determine the primary site from where the cancer originated, and has started treatment for it. Many women with axilla adenocarcinoma and normal mammograms have breast cancer, which may be identified in some of them by breast MRI or on pathological examination of surgically removed breast.
If she has occult breast primary with axillary involvement only, then she has stage 2 breast cancer. (However, we need to confirm that indeed she has no other metastases).
One approach to treatment of women with axillary node adenocarcinoma with unknown primary involves breast surgery followed by chemotherapy and radiation.
Please discuss in detail with the treating oncologist.
Best of Luck, and God Bless!
Dr Saini

[selam1]

Thank you for taking the time to respond to my questions.