No, she will need chest wall and probably axillia radiation, maybe neck also. The radiation you are refffering to is for small tumor and lumpectomies with no nodal invovlement.
For others seeing on this question by Abmisha, I am repeating my reply below:
The use of "Sinlge-Dose Breast Cancer Radiation" (used ONLY at the time of breast conserving BC surgery) is promising, but still largely investigational.
So that you do not feel bad that this advancement in BC cancer treatment was not available in time for use with your mother, let me also point that it is only inidicated for with people with one tumor and no spread to the lymph nodes, so your mother would not have been a candidate for this type of treatment in any case.
Rest assured that your mother is being given the best treatment for her type, stage, and grade of BC.
Best wishes to you both...
Duplicate post, previously answered in your thread titled "Hormone therapy", which can be reached by this link:
http://www.medhelp.org/posts/Breast-Cancer/Hormone-Therapy/show/1248043