DISEASE CHARACTERISTICS:

• Histologically confirmed breast cancer meeting 1 of the following criteria:

  • Metastatic disease (M1)
  • Multiple sites of new disease that is clinically obvious metastatic disease (e.g., multiple sites of new osseous disease)
• Measurable or nonmeasurable disease
• No known brain or CNS metastases

• Hormone receptor status:

  • Estrogen-receptor positive* AND/OR
  • Progesterone-receptor positive* NOTE: *Positivity defined as estrogen binding of > 10 fmol/mg cytosol protein by ligand binding assay or positive by immunohistochemistry

PATIENT CHARACTERISTICS:

Age

• Not specified

Sex

• Female

Menopausal status

• Postmenopausal, as defined by 1 of the following:

  • Prior bilateral oophorectomy
  • More than 12 months since last menstrual period with no prior hysterectomy
  • At least 55 years of age with prior hysterectomy
  • Under 55 years of age with a prior hysterectomy without oophorectomy and with estradiol and follicle-stimulating hormone levels consistent with menopause

Performance status

• Zubrod 0-2

Life expectancy

• Not specified

Hematopoietic

• No bleeding diathesis (e.g., disseminated intravascular coagulation or clotting factor deficiency)

Hepatic

• INR ≤ 1.6

Renal

• Not specified

Other

• HIV negative
• No other malignancy within the past 5 years except adequately treated basal cell or squamous cell skin cancer, carcinoma in situ of the cervix, or adequately treated stage I or II cancer currently in complete remission

PRIOR CONCURRENT THERAPY:

Biologic therapy

• No prior immunotherapy for recurrent or metastatic disease

Chemotherapy

• No prior chemotherapy for recurrent or metastatic disease
• More than 12 months since prior adjuvant or neoadjuvant chemotherapy
• No concurrent chemotherapy for malignancy

Endocrine therapy

• Prior adjuvant hormonal therapy allowed

• At least 12 months since prior adjuvant luteinizing hormone-releasing hormone (LHRH) analogues

  • Menstrual periods must not have resumed since LHRH therapy
• More than 12 months since prior adjuvant or neoadjuvant aromatase inhibitors (e.g., anastrozole, letrozole, or exemestane)
• More than 12 months since prior fulvestrant
• No prior hormonal therapy for recurrent or metastatic disease
• No other concurrent hormonal therapy for malignancy
• No concurrent hormone replacement therapy

Radiotherapy

• Not specified

Surgery

• Not specified

Other

• No long-term anticoagulant therapy (except antiplatelet therapy)