Bicalutamide in Treating Patients With Metastatic Breast Cancer

OBJECTIVES:

Primary

• Determine the 6-month efficacy rate of bicalutamide as first-, second-, or third-line therapy in patients with androgen receptor-positive and estrogen receptor- and progesterone receptor-negative metastatic breast cancer.

Secondary

• Determine the 6-month progression-free survival of patients treated with this drug.
• Evaluate the safety of this drug in these patients.
• Evaluate changes in estradiol, total and free testosterone, and sex-hormone binding globulin in response to androgen blockade in patients treated with this drug.
• Evaluate tissue, including cytokeratins 5/6 and 17, SPDEF, ALCAM, ERBB2, FGFR4, and prostate-specific antigen (PSA), using immunohistochemical analysis in patients treated with this drug.

OUTLINE: This is a open-label study.

Patients receive oral bicalutamide once daily for 4 weeks. Treatment repeats every 4 weeks for 6 months in the absence of disease progression or unacceptable toxicity. Patients achieving complete response, partial response, or stable disease may continue to receive bicalutamide as above at the discretion of the investigator.

Patients undergo blood and tissue sample collection for correlative studies. Samples are analyzed for hormonal levels, including estradiol, total testosterone, free testosterone, and sex-hormone binding globulin, and proteins, including ALCAM, SPEDF, and CK 5/6, by immunohistochemical analysis at baseline, after course 1, and at the end of the study.

After completion of study treatment, patients are followed every 3 months.

PROJECTED ACCRUAL: A total of 28 patients will be accrued for this study.

DISEASE CHARACTERISTICS:

• Histologically confirmed adenocarcinoma of the breast

• Stage IV disease
• Measurable or non-measurable disease
• Patients with HER2/neu-positive disease must have received prior trastuzumab (Herceptin®)
• No active brain metastases or leptomeningeal disease

• History of brain metastases allowed provided lesions are stable for at least 3 months as documented by head CT scan or MRI of the brain
• Hormone receptor status:

• Estrogen receptor- and progesterone receptor-negative*
• Androgen receptor-positive* NOTE: *Samples are considered positive if greater than 10% of cell nuclei are immunoreactive

PATIENT CHARACTERISTICS:

• Male or female
• Menopausal status not specified
• ECOG performance status 0-1
• Absolute neutrophil count ≥ 1,500/mm³
• Platelet count ≥ 100,000/mm³
• Hemoglobin ≥ 9 g/dL
• AST and ALT ≤ 2.5 times upper limit of normal (ULN)
• Bilirubin ≤ 1.5 times ULN
• Alkaline phosphatase ≤ 2.5 times ULN (unless bone metastases are present in the absence of liver metastases)
• Creatinine ≤ 1.5 mg/dL
• Not pregnant or nursing
• Negative pregnancy test
• Fertile patients must use effective contraception
• No serious medical or psychiatric illness
• No serious active infection
• No other malignancy within the past 5 years except nonmelanoma skin cancer
• No hypersensitivity reaction to bicalutamide or any of the tablet's components

PRIOR CONCURRENT THERAPY:

• At least 2 weeks since prior cytotoxic chemotherapy and recovered
• At least 3 weeks since prior investigational drugs
• At least 4 weeks since prior major surgery and recovered
• Prior neoadjuvant or adjuvant chemotherapy allowed

• Any number of chemotherapy regimens are allowed for metastatic disease
• Prior hormonal therapy allowed
• No concurrent chemotherapy, other hormonal therapy, immunotherapy, or biological therapy
• No concurrent trastuzumab (Herceptin®)
• No concurrent enrollment in another clinical trial in which investigational procedures are performed or investigational therapies are administered