Trastuzumab and External Beam Radiation Therapy in Treating Women With Stage III or Stage IV Breast Cancer

Radiation therapy will consist of 50Gy in 2Gy fractions to the breast/chest wall and regional lymphatics for 5 consecutive days up to 5 weeks for surgical candidates and 7 weeks for non-surgical candidates

Patients who are already receiving weekly Herceptin® will continue weekly Herceptin®, 2mg/kg IV on day 1 of each week of radiotherapy. Patients who have not been receiving weekly Herceptin® as a component of systemic therapy will begin Herceptin® one week prior to beginning radiotherapy with a loading dose of 4mg/kg followed by weekly Herceptin® at 2mg/kg on day 1 of each week of radiotherapy