Fulvestrant in Treating Patients With Advanced Prostate Cancer

DISEASE CHARACTERISTICS: Histologically or cytologically confirmed adenocarcinoma of the prostate Advanced disease Must have androgen-independent prostate cancer meeting the following criteria: Evidence of rising prostate-specific antigen (PSA) level and absolute value ≥ 5 ng/mL based on 2 measurements taken ≥ 2 weeks apart (measurements must be done after androgen deprivation [orchiectomy or luteinizing hormone-release hormone (LHRH) analogue] and antiandrogen withdrawal) Rising PSA required for ≥ 28 days after antiandrogen or progestational therapy for prostate cancer (≥ 42 days after bicalutamide or nilutamide) Testosterone < 50 ng/mL (unless surgically castrated) Measurable or evaluable disease PSA elevation constitutes evaluable disease PATIENT CHARACTERISTICS: Performance status ECOG 0-2 Life expectancy Not specified Hematopoietic WBC > 3,000/mm^3 Neutrophil count ≥ 1,500/mm^3 Platelet count ≥ 100,000/mm^3 Hemoglobin ≥ 8 g/dL (transfusion or epoetin alfa allowed) No bleeding diathesis (e.g., disseminated intravascular coagulation or clotting factor deficiency) Hepatic Bilirubin normal Gilbert's disease with bilirubin ≤ 3 times upper limit of normal (ULN) allowed in the absence of other etiology (e.g., hemolysis-reticulocyte count < 5%) and liver function tests normal SGOT and/or SGPT ≤ 2 times ULN INR < 1.6 Renal Creatinine < 2.5 mg/dL Cardiovascular No unstable cardiac disease requiring medication No new onset crescendo or rest angina Stable exertional angina allowed Other Fertile patients must use effective barrier contraception during and for 3 months after completion of study treatment No other active malignancy within the past 2 years except nonmelanoma skin cancer or superficial bladder cancer No history of significant neurologic or psychiatric disorders, including psychotic disorders, dementia, or seizures No other serious illness or medical condition No active infection No known hypersensitivity to active or inactive excipients of fulvestrant (e.g., castor oil or mannitol) PRIOR CONCURRENT THERAPY: Biologic therapy Prior retinoids, vaccines, and cytokines are not considered cytotoxic and are allowed Chemotherapy No more than 1 prior cytotoxic chemotherapy regimen More than 3 weeks since prior chemotherapy (6 weeks for mitomycin or nitrosoureas) No concurrent chemotherapy Endocrine therapy See Disease Characteristics Prior glucocorticoids, antiandrogens, progestational agents, estrogens, and LHRH analogues are not considered cytotoxic and are allowed At least 4 weeks since prior flutamide (6 weeks for bicalutamide or nilutamide) Concurrent megestrol acetate allowed at a stable dose of ≤ 40 mg/day Concurrent androgen deprivation using LHRH analogues allowed but must continue during study treatment or orchiectomy is required to maintain castrate levels of testosterone Radiotherapy More than 3 weeks since prior radiotherapy No concurrent radiotherapy Surgery See Disease Characteristics See Endocrine therapy Other Recovered from all prior therapy Prior cholecalciferol analogues, ketoconazole, aminoglutethimide, peroxisome-proliferation-activated receptor-gamma agonists or antagonists, or PC-SPES are not considered cytotoxic and are allowed No prior long-term anticoagulation therapy (antiplatelet therapy allowed) More than 4 weeks since prior investigational drugs No other concurrent anticancer therapy (e.g., PC-SPES) No concurrent bisphosphonates unless receiving a stable dose at study entry No concurrent therapy that may alter androgen metabolism or androgen levels No concurrent full anticoagulation