Tamoxifen Citrate in Treating Premenopausal Women With Estrogen Receptor-Positive Breast Cancer

PRIMARY OBJECTIVES:

I. Investigate the status of ERalpha-p53 interaction in ERalpha-positive, p53-wild type
breast tumors in untreated patients and examine how tamoxifen (tamoxifen citrate) therapy
modifies this interaction.

II. To confirm the wild type status of p53 and analyze the functional status of p53 pathway
by monitoring expression of selected p53-target genes in tumors in patients who have or have
not been treated with tamoxifen.

OUTLINE: Patients are randomized to 1 of 2 treatment arms.

Arm I: Patients receive standard of care surgical therapy. Patients may undergo standard
surgery.

Arm II: Patients receive tamoxifen citrate orally (PO) daily for 4 weeks in the absence of
disease progression or unacceptable toxicity. Patients may then undergo standard surgery.

Inclusion Criteria:

- The patient must consent to be in the study and must have signed an approved consent
form conforming to institutional guidelines

- Core biopsy should definitively demonstrate invasive carcinoma

- Invasive carcinoma should be ERalpha receptor positive

- The tumor should be approximately at least 1 cm, to account for variability in
imaging and imaging occult disease (physical exam, mammography, ultrasound); we
recognize that from time to time because of this variation, there might not be enough
tissue available for analysis after surgical excision but this will allow the
greatest opportunity to capture as many eligible patients as possible

- Patients in whom surgical excision of the tumor is part of standard of care
management

- Eastern Cooperative Oncology Group (ECOG) score of 0 or 1

- Negative serum or urine beta-human chorionic gonadotropin (hCG) pregnancy test at
screening for patients of child-bearing potential (this is routinely done if the
patient is premenopausal and having surgery)

- Consent to participate in Data Bank and BioRepository (DBBR)

Exclusion Criteria:

- Male patients are not eligible for this study

- Female patients with inoperable tumors or women with stage 4 disease diagnosed on
computed tomography (CT), positron emission tomography (PET), PET/CT or bone scan

- Patients with diagnosis by fine needle aspiration (FNA) cytology only

- Pregnant or lactating women

- Prior therapy for breast cancer, including irradiation, chemo-, immuno- and/or
hormonal therapy

- Patients receiving any hormonal therapy, e.g.,ovarian hormonal replacement therapy,
infertility medications etc., are not eligible

- Nonmalignant systemic disease (cardiovascular, renal, hepatic, etc.) that would
preclude the patient from being subjected to surgical excision

- Psychiatric or addictive disorders that would preclude obtaining informed consent

- Patients known or suspected to have hypercoagulable syndrome or with history of
venous or arterial thrombosis, stroke, transient ischemic attack (TIA), or pulmonary
embolism

- Women with non-invasive disease or microinvasion are not eligible

- Women undergoing neoadjuvant chemotherapy are not eligible

- Women currently on tamoxifen for prevention are not eligible

- Patients shall not receive any herbal/alternative therapies such as flaxseed or soy
products or black cohosh

- Patients with a known mutation in p53 (Li Fraumer/ Syndrome)