Soy Protein/Effexor Hormone Therapy for Prostate Cancer

OBJECTIVES: Primary * Assess the effect of soy protein/isoflavones and venlafaxine on the hot flash symptom severity score in patients undergoing hormonal manipulation for treatment of prostate cancer. Secondary * Assess the effect of soy protein/isoflavones and venlafaxine on quality of life of these patients. * Monitor and assess the participant drop out rate. OUTLINE: This is a randomized, double-blind, multicenter study. Patients are stratified according to severity of disease (metastatic vs nonmetastatic) and baseline severity of hot flashes. Patients are randomized to 1 of 4 treatment arms. * Arm I: Patients receive oral placebo pill and oral soy protein/isoflavones powder once daily. * Arm II: Patients receive oral venlafaxine and oral placebo powder once daily. * Arm III: Patients receive oral venlafaxine and oral soy protein/isoflavones powder once daily. * Arm IV: Patients receive oral placebo pill and oral placebo powder once daily. Treatment in all arms continues for 12 weeks in the absence of disease progression or unacceptable toxicity. After 12 weeks of treatment, patients in arms I and III receive a tapered dose of oral venlafaxine once daily for 1 week. Patients complete a vasomotor symptom diary once daily beginning 7 days before the initiation of study treatment and continuing until the completion of study treatment. Quality of life is assessed at baseline and at week 12. PROJECTED ACCRUAL: A total of 176 patients will be accrued for this study.