Effect of Trastuzumab on Disease Free Survival in Early Stage HER2-Negative Breast Cancer Patients With ERBB2 Expressing Disseminated Tumor Cells

Inclusion Criteria:

-Histologically confirmed HER2-negative primary invasive ductal or invasive lobular breast carcinoma. For patients enrolling for neoadjuvant treatment, diagnosis must be clinical stage II or III; for patients enrolling for adjuvant treatment, diagnosis must be pathologic stage IIA to IIIC.

Standard HER2 testing will be performed in the surgical specimen at Washington University according to the standard of care in the Department of Pathology. A HER2-negative primary breast cancer sample from a patient eligible for randomization should have a HER2 IHC score of 0 or 1+ Those patients with IHC score of 2+ should be HER2 FISH-negative in standard testing.

Patient will have undergone staging studies including a CT of the chest/abdomen/pelvis and bone scan and/or PET scan either prior to the initiation of treatment or prior to entry into the trial.

• Presence of bone marrow ERBB2 expressing DTCs at the time of diagnosis; bone marrow aspiration will be performed in consented patients to evaluate DTCs following pre-registration provided patients meet all eligibility criteria as described in this section.
• A candidate for adjuvant or neoadjuvant chemotherapy. Adjuvant tamoxifen or aromatase inhibitors treatment will be allowed for hormone receptor-positive patients.
• At least 18 years old.
• Eastern Cooperative Oncology Group (ECOG) performance status ≤ 1.
• Adequate cardiac function as demonstrated by LVEF of >55% performed no more than 2 weeks prior to randomization.

• Normal organ and marrow function as defined below:

  • leukocytes ≥3,000/mcL
  • absolute neutrophil count ≥1,500/mcL
  • platelets ≥100,000/mcL
  • hemoglobin ≥ 10 g/dL
  • total bilirubin ≤within institutional upper limits of normal unless related to primary disease
  • AST(SGOT)/ALT(SGPT) ≤2.0 X institutional upper limit of normal
  • Creatinine ≤ 1.5 institutional upper limits of normal OR creatinine clearance ≥60 mL/min/1.73 m2 for patients with creatinine levels above institutional normal
• Patient (or legally authorized representative) must be able to understand and willing to sign a written informed consent document.
• If a woman of childbearing potential, patient must use dual forms of effective contraception.

Exclusion Criteria:

• Evidence of distant metastasis present by CT scan, bone scan, or physical exam.
• Undergoing treatment with other standard or investigational anti-cancer agents at the time of enrollment.
• Prior chemotherapy within the 4 weeks prior to pre-registration (6 weeks for nitrosureas/mitomycin).
• Prior radiation therapy within the 4 weeks prior to pre-registration.
• Previous treatment with trastuzumab or any other Her2 targeted therapy.
• History of allergic reactions attributed to compounds of similar chemical or biologic composition to trastuzumab.
• Presence of an uncontrolled intercurrent illness including, but not limited to, ongoing or active infection, symptomatic congestive heart failure, unstable angina pectoris, cardiac arrhythmia, or psychiatric illness/social situations that would limit compliance with study requirements.
• History of other malignancy ≤ 5 years previous with the exception of basal cell or squamous cell carcinoma of the skin which were treated with local resection only or carcinoma in situ of the cervix.
• Pregnant or breastfeeding. Patient must have a negative serum pregnancy test ≤ 7 days from date of registration (if a woman of childbearing potential).

Women of childbearing potential are defined as follows:

• Women with regular menses
• Women with amenorrhea, irregular cycles, or using a contraceptive method that precludes withdrawal bleeding
• Women who have had a tubal ligation.

Women are considered not to be of childbearing potential for the following reasons:

• The patient has undergone hysterectomy and/or bilateral oophorectomy.

• The patient is post-menopausal defined by amenorrhea for at least 1 year in a woman > 45 years old.

  • Clinically important history of active liver disease, including viral or other hepatitis or cirrhosis.
  • Uncontrolled hypocalcemia, hypomagnesemia, hyponatremia, or hypokalemia defined as less than the lower limit of normal for the institution despite adequate electrolyte supplementation.
  • Symptomatic intrinsic lung disease or extensive tumor involvement of the lungs resulting in dyspnea at rest.

Inclusion of Women and Minorities

-Breast cancer is rare in men and children. Therefore, this trial is only open to women of all races and ethnic groups.