Participants with stage II or stage III node-positive breast cancer, or T3N0 node-negative will receive hypofractionated radiation for 4 weeks. We hypothesize that patients receiving a shorter course of radiation will have reduced lymphedema. Lymphedema is diagnosed when the patient's arm circumference measures 10% or more as compared to pre-treatment (baseline) arm circumference measurement. Secondary endpoints will address the effectiveness, quality of life, and side effect profile of a shortened course of treatment.