Radiation Therapy With or Without Trastuzumab as Treatment for Women with Ductal Carcinoma In Situ after Lumpectomy
The purpose of this study is to find out if taking trastuzumab with radiation therapy works any better than radiation therapy without trastuzumab when treating women with ductal breast cancer in situ who have undergone lumpectomy. Radiation therapy uses high-energy x-rays to kill tumor cells. Trastuzumab blocks tumor growth in other ways. The primary objective is to determine which treatment works best to prevent subsequent occurrence or recurrence of breast cancer or ductal carcinoma in situ (DCIS). The study will enroll 2,000 participants from many cancer centers in the US. In addition to other conditions for enrollment, women with HER2-positive DCIS that was removed by lumpectomy within the past 120 days may be eligible. Eligible patients must not be candidates for mastectomy, cannot have a positive lymph node, and cannot have a history of heart disease. Eligible patients cannot have had prior whole or partial breast radiation therapy.