You will have routine surgery for DCIS (either segmental mastectomy, mastectomy with or without reconstruction, and possible sentinel lymph node biopsy) approximately 14 to 28 days after being given Herceptin. If a segmental mastectomy was performed as part of our standard practice you will be evaluated by a radiation oncologist following surgery. After your surgery, patients will also be evaluated by a breast medical oncologist to determine if any additional standard therapy is needed.