111 Indium CHX-A DTPA Trastuzumab (Indium-Herceptin) for Imaging Breast Cancer

Background: * Some breast cancer cells have specific proteins (receptors) on their surface that make the tumor grow faster than normal cells. One of these receptors is called HER2/neu. * An FDA-approved drug called Herceptin attaches to HER2/neu if it is present on the cancer cell. * Indium-Herceptin is an agent in which a tiny amount of radioactivity called Indium has been attached to a tiny amount of Herceptin. Objectives: -To see if Indium-Herceptin provides information about the characteristics of the breast cancer in women whose tumors express HER2/neu and those whose tumors do not. Eligibility: -Women 18 years or older with primary or metastatic breast cancer who have not received treatment with herceptin for at least 6 months before enrollment into the study. Design: * Tissue from the patient s original breast or tumor biopsy is analyzed for HER2/neu status. * Patients have a physical examination and review of medical records. * Patients receive an injection of Indium-Herceptin, followed by scanning with a gamma camera that detects the radioactivity in the Indium-Herceptin. * Patients return to the clinic 1, 2, 3 and 7 days later for repeat imaging to determine the best time to image after injection of Indium-Herceptin. * Blood samples are obtained every day of scanning to monitor the effects, if any, of the Indium-Herceptin and to see how fast the agent leaves the body.