Trial Of PreoperAtive Radiation (TOPAz): A Randomized Trial Comparing Hypofractionated Versus Conventionally Fractionated Preoperative Radiation Followed by Mastectomy With Immediate Autologous Breast Reconstruction With Integrated Nanomechanical Biomarker Evaluation

This trial is comparing two radiation delivery schedules — a shorter, higher-dose-per-session approach (hypofractionated) versus the traditional longer course (conventional fractionation) — given before mastectomy in people with locally advanced breast cancer who plan to have immediate reconstruction using their own body tissue (called autologous reconstruction). **You may be eligible if...** - You are 18 or older with invasive breast cancer requiring mastectomy - Your cancer is locally advanced (stage T3-T4c) or involves lymph nodes (N1-N3) - You are planning to have mastectomy with immediate autologous (tissue-based) reconstruction - You have not yet had mastectomy at the time of enrollment **You may NOT be eligible if...** - You are planning implant-based (rather than tissue-based) reconstruction - Your cancer has spread to distant organs (unless specific IBC criteria are met) - You have previous radiation to the chest area - You cannot tolerate the planned radiation or surgery Talk to your doctor to see if this trial is right for you.