Pomegranate Extract in Treating Patients With Rising Prostate-Specific Antigen Levels After Surgery or Radiation Therapy for Localized Prostate Cancer

OBJECTIVES: Primary * Evaluate the effects of pomegranate extract in patients with and rising prostate-specific antigen (PSA) levels after surgery or radiotherapy for localized prostate cancer. * Determine the effect of a daily oral dose of pomegranate extract on the absolute value of PSA and on the change in PSA doubling time in these patients. Secondary * Assess toxicities associated with daily oral dosing of pomegranate extract in these patients. * Determine the effect of pomegranate extract on positive PSA doubling-time outcome, defined as greater than 150% baseline or a negative post-treatment PSA doubling time (i.e., declining PSA). OUTLINE: This is a multicenter, double-blind, placebo-controlled, randomized study. Patients are stratified according to participating center. Patients are randomized to 1 of 2 treatment arms. * Arm I: Patients receive oral pomegranate extract daily. * Arm II: Patients receive oral placebo daily. Treatment in both arms continues for up to 1 year in the absence of disease progression. PROJECTED ACCRUAL: A total of 180 patients will be accrued for this study.