Shortening Adjuvant Photon and Proton Irradiation (SAPPHIRe-II): A 4 Cohort, Randomized, Phase II Multi-center Trial Evaluating Shorter Schedules of Adjuvant Regional Nodal Irradiation Among Women and Men With Node-positive and High-risk Node-negative Invasive Breast Cancer

This study (SAPPHIRe-II) is testing whether shorter courses of radiation therapy to the lymph nodes work just as well as standard-length courses for women and men with breast cancer that has spread to the lymph nodes or has high-risk features. **You may be eligible if...** - You have been diagnosed with invasive breast cancer confirmed by biopsy - Your surgeon and radiation oncologist have recommended radiation to the regional lymph nodes - Your surgical margins are clear (no cancer at the edges) - No more than 12 weeks have passed since your last surgery or chemotherapy - You are 18 years or older **You may NOT be eligible if...** - You have active cancer in both breasts at the time of diagnosis (bilateral breast cancer may have specific criteria) - Your surgical margins are not clear - More than 12 weeks have passed since your last treatment - You are under 18 years old Talk to your doctor to see if this trial is right for you.