RATIONALE: High doses of esterified estrogens may stop the growth of breast cancer cells
that no longer respond to hormone therapy.
PURPOSE: This phase II trial is studying how well high-dose esterified estrogens work in
treating postmenopausal women with metastatic breast cancer that has failed previous hormone
- Determine the clinical response rate in postmenopausal women with estrogen and/or
progesterone receptor-positive metastatic breast cancer that has failed prior
sequential endocrine therapy treated with high-dose esterified estrogens (Menest^®).
- Determine time to disease progression in patients treated with this drug.
- Determine the toxic effects of this drug in these patients.
OUTLINE: Patients receive oral high-dose esterified estrogens (Menest^®) 3 times daily.
Treatment continues in the absence of disease progression or unacceptable toxicity.
After completion of study treatment, patients are followed for 2 months.
PROJECTED ACCRUAL: A total of 18-35 patients will be accrued for this study within 2 years.
- Histologically confirmed breast cancer
- Metastatic disease
- Documented disease progression
- Must have received and subsequently failed (due to disease progression) ≥ 2
prior sequential endocrine therapies for treatment of metastatic breast cancer
- Disease progression during adjuvant tamoxifen is considered 1 prior therapy
- The 2 most recent treatments must have been endocrine agents
- At least 1 objective measurable disease parameter
- Brain metastases allowed provided both of the following criteria are met:
- Brain metastases were previously treated AND are currently stable
- Brain metastases are not the only site of metastatic disease
- Hormone receptor status
- Estrogen and/or progesterone receptor-positive tumor
- 18 and over
- Postmenopausal, as defined by any of the following:
- At least 50 years of age with an intact uterus AND amenorrheic for the past 12
- At least 50 years of age without a uterus AND follicle-stimulating hormone (FSH)
level within postmenopausal range
- Under 50 years of age and FSH level within postmenopausal range
- Prior bilateral oophorectomy
- ECOG 0-2
- At least 6 months
- Adequate hematologic function
- Adequate hepatic function
- Bilirubin ≤ 1.5 times upper limit of normal
- No history of hepatic adenoma
- Adequate renal function
- No history of hypercalcemia or severe hypocalcemia
- No history of thrombophlebitis or thromboembolic disorders associated with prior
- No active thrombophlebitis or thromboembolic disorders
- No history of uncontrolled hypertension
- Not pregnant
- No undiagnosed abnormal vaginal bleeding
- No other serious medical illness
- No psychiatric illness that would preclude giving informed consent
- No other invasive malignancy within the past 5 years except curatively treated basal
cell or squamous cell skin cancer or carcinoma in situ of the cervix
PRIOR CONCURRENT THERAPY:
- Not specified
- Prior chemotherapy for metastatic disease allowed
- Prior adjuvant chemotherapy allowed
- See Disease Characteristics
- Prior radiotherapy allowed provided the only site of measurable disease was not
- Not specified