Green Tea Extract in Treating Patients With Metastatic Prostate Cancer That Has Not Responded to Hormone Therapy

OBJECTIVES: I. Determine the effectiveness and toxicity of green tea extract in patients
with androgen-independent metastatic prostate cancer. II. Determine the response rate and
response duration in patients treated with this regimen. III. Determine whether a decline in
prostate-specific antigen (PSA) coincides with evidence of disease regression in these
patients.

OUTLINE: Patients receive oral green tea extract six times daily for 4 months. Patients with
a 50% decline in PSA, complete or partial response, or stable disease after 4 months
continue treatment in the absence of disease progression or unacceptable toxicity. Patients
with disease progression after 4 months receive no further treatment. Patients are followed
every 3 months for 5 years or until disease progression. If disease progression, patients
are followed every 6 months for 5 years.

DISEASE CHARACTERISTICS: Clinically proven androgen-independent metastatic prostate cancer
Radiological, physically palpable, and/or biochemical evidence of progression Increase in
PSA after orchiectomy or hormonal treatment No symptoms directly attributable to
metastatic disease No CNS metastases or carcinomatous meningitis

PATIENT CHARACTERISTICS: Age: 18 and over Performance status: ECOG 0-2 Life expectancy: At
least 12 weeks Hematopoietic: Not specified Hepatic: Bilirubin no greater than 1.5 mg/dL
Renal: Creatinine no greater than 2 times upper limit of normal Cardiovascular: No
uncontrolled high blood pressure No unstable angina No symptomatic congestive heart
failure No uncontrolled cardiac arrhythmias No myocardial infarction in past 6 months
Other: No other malignancy within the past 5 years except basal cell skin cancer No
uncontrolled diabetes mellitus or inability to tolerate high sugar content of green tea at
discretion of oncologist No other medical or psychiatric conditions that would preclude
study

PRIOR CONCURRENT THERAPY: Biologic therapy: At least 4 weeks since prior immunotherapy
Chemotherapy: At least 4 weeks since prior chemotherapy No concurrent chemotherapy
Endocrine therapy: At least 4 weeks since prior flutamide or megestrol At least 6 weeks
since prior longer-acting hormonal agents such as bicalutamide At least 4 weeks since
prior hormonal therapy, except luteinizing hormone- releasing hormone agonist No
concurrent hormonal therapy, including corticosteroids for cancer treatment Radiotherapy:
No concurrent radiotherapy Surgery: See Disease Characteristics Other: No other concurrent
investigational agents