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.