Vitamin E Supplements in Preventing Cancer in Patients at Risk of Prostate Cancer or Who Have Prostate Cancer

OBJECTIVES:

• Determine the effect of tocopherol supplementation on plasma and urine levels of α-, γ-, and δ-tocopherols, PSA, and prostaglandin E_2 by comparing the blood and urine samples collected before and after the supplementation in patients with prostate cancer.
• Test the hypothesis that the supplementation reduced oxidative and nitrosative stress by measuring plasma levels of F_2-isoprostane, C-reactive protein, and 3-nitrotyrosine as well as urinary levels of 8-hydroxy-2-deoxyguanosine (8-OHdG).
• Determine the levels of α-, γ-, and δ-tocopherols in prostate tissues and analyze immunohistochemically (IHC) for cell proliferation, apoptosis, cyclooxygenase-2, 8-OHdG, and 3-nitropyrosine levels in prostate cancer/tissue slides.

OUTLINE: Patients are randomized into 1 of 3 arms.

• Arm I: Patients receive no supplementation.
• Arm II: Patients receive oral high γ-tocopherol vitamin E supplementation once daily for 1 week.
• Arm III: Patients receive oral high γ-tocopherol vitamin E supplementation once daily for 2 weeks.

Blood, urine, and tissue samples are collected periodically and analyzed for oxidative/nitrosative stress and other markers (i.e., F2-isoprostane, 8-OHdG, 3-nitrotyrosine, prostaglandin E2, C-reactive protein, and PSA), biomarkers in prostate tumors and nontumorous tissues (i.e., 8-OHdG, 3-nitrotyrosine, and cyclooxygenase-2) by IHC, and pharmacokinetics by high-performance liquid chromatography.

DISEASE CHARACTERISTICS:

• Meets one of the following criteria:

• Abnormal digital rectal examination or abnormal prostate specific antigen (> 4.0 ng/mL)
• Obstructing prostate
• Biopsy-proven prostate cancer
• Scheduled to undergo prostate surgery (i.e., transurethral prostatectomy or prostatectomy)

PATIENT CHARACTERISTICS:

• No uncontrolled diabetes, uncontrolled blood pressure, chronic congestive heart failure, or history of renal insufficiency
• No personal or family history of a bleeding disorder
• No known history of problems absorbing dietary fats (e.g., Crohn's disease, cystic fibrosis)

PRIOR CONCURRENT THERAPY:

• More than 2 weeks since prior NSAIDs or corticosteroids
• No concurrent supplementation of vitamin E (a multivitamin containing ≤ 60 IU of vitamin E is allowed)
• No concurrent colestipol or orlistat
• No concurrent warfarin or dicumarol