A Vaccine (H2NVAC) Before Surgery for the Treatment of HER2-Expressing Ductal Carcinoma In Situ

Required: HER2 (ERBB2) expression (immunohistochemistry +1, +2, or +3)

Any degree of HER2 expression as performed on the diagnostic clinical biopsy defined by immunohistochemistry +1, +2, or +3

Cannot have received: prior therapy for current DCIS

Exception: Patients who received tamoxifen, raloxifene, aromatase inhibitor or another agent for prevention of breast cancer may be included as long as the patient has discontinued the treatment at least 2 months prior to baseline study biopsy

Patients must not have received any prior therapy for current DCIS

Cannot have received: concurrent endocrine therapy (tamoxifen, aromatase inhibitor)

Exception: Standard adjuvant endocrine therapy after completion of vaccination and surgery is allowed

Concurrent use of endocrine therapy during the vaccination/preoperative period is not allowed

Cannot have received: investigational agent

Receiving any other investigational agent

Cannot have received: prior hypersensitivity or adverse reaction to GM-CSF (GM-CSF)

Any prior hypersensitivity or adverse reaction to GM-CSF

Cannot have received: prior trastuzumab-related cardiac toxicity (trastuzumab)

History of trastuzumab-related cardiac toxicity requiring interruption or discontinuation of therapy, even if left ventricular ejection fraction (LVEF) fully recovered

Cannot have received: prior ipsilateral radiation to the current affected breast with DCIS

History of ipsilateral radiation to the current affected breast with DCIS