Vaccine Therapy in Treating Patients Receiving Trastuzumab For HER2-Positive Stage IIIB-IV Breast Cancer

Inclusion Criteria: Stage IIIB or Stage IIIC breast cancer who are within 1 year of diagnosis and initiating treatment with chemotherapy and trastuzumab; and are in complete remission Stage IV breast cancer in first complete remission and defined as NED (no evidence of disease) or with stable bone only disease who are within 6 months of initiating maintenance trastuzumab NED status should be documented by chest/abdominal CT, PET or PET/CT within the last 90 days Bone only disease documented as stable or healed by PET, PET/CT, or MRI within the last 90 days; stable bone-only disease must be documented with bone scan performed within the last 6 months HER2 overexpression by IHC of 2+ or 3+, in the primary tumor or metastasis or documented gene amplification by FISH analysis; if overexpression is 2+ by IHC, then patients must have HER2 gene amplification documented by FISH Eligible subjects must have been treated to NED or stable bone only disease status with trastuzumab and/or chemotherapy and be off cytotoxic chemotherapy or immunosuppressive agents (e.g. systemic steroids) for at least 30 days prior to enrollment (concurrent hormonal therapy allowed; concurrent bisphosphonate therapy allowed) Patients on trastuzumab should continue trastuzumab monotherapy per standard of care (the dosing and schedule of trastuzumab should follow standard guidelines as described below: trastuzumab 2mg/kg IV weekly or trastuzumab 6mg/kg IV every 3 weeks) Subjects must have an ECOG Performance Status Score =< 1 Non-menopausal female subjects must agree to contraception for the remainder of their childbearing years Male subjects must use an acceptable form of contraception throughout the course of the study Hematocrit >= 30,000 Platelet count >= 100,000 WBC >= 3000/mcl Stable creatinine =< 2.0 mg/dl or a creatinine clearance greater than 60 ml/min Serum bilirubin < 1.5 mg/dl SGOT < 2x ULN Laboratory tests should be performed within 60 days of enrollment Subjects must have recovered from major infections and/or surgical procedures and, in the opinion of the investigator, not have any significant active concurrent medical illnesses precluding protocol treatment Patients on trastuzumab monotherapy must have adequate cardiac function as demonstrated by normal ejection fraction (EF) on MUGA scan or echocardiogram performed within last 6 months Exclusion Criteria: Subjects cannot be simultaneously enrolled in other treatment studies Patients cannot be receiving any other concurrent immunomodulators besides trastuzumab Any contraindication to receiving GM-CSF based vaccine products Cardiac disease, specifically restrictive cardiomyopathy, unstable angina within the last 6 months prior to enrollment, New York Heart Association functional class III-IV heart failure on active treatment with normalized LVEF on therapy, and symptomatic pericardial effusion Active autoimmune disease Subjects can not have active immunodeficiency disorder, e.g. HIV Cannot be pregnant or breast feeding