• Fatty acid synthase expression by immunohistochemistry at pre- and post-intervention [ Designated as safety issue: No ]
• Cell proliferation by Ki67-immunohistochemistry at pre- and post-intervention [ Designated as safety issue: No ]
• Phospholipid membrane composition by sucrose gradient ultracentrifugation at post-intervention [ Designated as safety issue: No ]
• Comparison of the synergistic effect of combined green tea and fish oil to placebo or green tea supplementation alone [ Designated as safety issue: No ]

• Fatty acid synthase expression by immunohistochemistry at pre- and post-intervention
• Cell proliferation by Ki67-immunohistochemistry at pre- and post-intervention
• Phospholipid membrane composition by sucrose gradient ultracentrifugation at post-intervention

• Sterol regulatory element binding protein expression by immunohistochemistry at pre- and post-intervention [ Designated as safety issue: No ]
• Apoptosis as measured by TUNEL at pre- and post-intervention [ Designated as safety issue: No ]
• Bone formation and loss by serum and urine osteocalcin and N-telopeptides at pre- and post-intervention [ Designated as safety issue: No ]

• Sterol regulatory element binding protein expression by immunohistochemistry at pre- and post-intervention
• Apoptosis as measured by TUNEL at pre- and post-intervention
• Bone formation and loss by serum and urine osteocalcin and N-telopeptides at pre- and post-intervention

RATIONALE: Chemoprevention is the use of certain drugs to keep cancer from forming, growing, or coming back. The use of fish oil and/or green tea may prevent prostate cancer.

PURPOSE: This randomized clinical trial is studying how well a fish oil and/or green tea supplement works in preventing prostate cancer in patients with prostatic intraepithelial neoplasia or who are at risk for developing prostate cancer.

OBJECTIVES:

• Determine the cancer preventing effects of fish oil supplementation and green tea extract use on markers of alteration in lipid metabolism in prostate tissue samples.

OUTLINE: This is a randomized, double-blind, placebo-controlled study. Patients are stratified according to age (under 65 vs 65 and over). Patients are randomized to 1 of 4 treatment arms.

• Arm I: Patients receive oral fish oil three times daily and oral green tea extract twice daily.
• Arm II: Patients receive a placebo three times daily and oral green tea extract twice daily.
• Arm III: Patients receive oral fish oil three times daily and a placebo twice daily.
• Arm IV: Patients receive one placebo three times daily and another placebo twice daily.

Treatment in both arms continues for up to 20 weeks in the absence of disease progression or unacceptable toxicity.

All patients undergo a prostate biopsy on the last day of study treatment.

After completion of study treatment, patients are followed for 30 days.

PROJECTED ACCRUAL: A total of 144 patients will be accrued for this study.

• Precancerous/Nonmalignant Condition
• Prostate Cancer

• Dietary Supplement: green tea extract
• Dietary Supplement: omega-3 fatty acids
• Other: placebo

• Experimental: Patients receive oral fish oil three times daily and oral green tea extract twice daily.
• Experimental: Patients receive a placebo three times daily and oral green tea extract twice daily.
• Experimental: Patients receive oral fish oil three times daily and a placebo twice daily
• Placebo Comparator: Patients receive one placebo three times daily and another placebo twice daily.

DISEASE CHARACTERISTICS:

• No definitive prostate cancer on initial biopsy

  • Patients may receive a repeat biopsy of the prostate

PATIENT CHARACTERISTICS:

Hematopoietic

• No hemophilia or von Willebrand's disease (patient-reported)
• No other bleeding disorder (patient-reported)

Hepatic

• Total bilirubin normal

Cardiovascular

• No implantable cardioverter defibrillator with episodes of ventricular tachycardia or ventricular fibrillation within the past 3 months

Other

• No known allergy or sensitivity to fish oil, olive oil, or green tea
• No significant active medical illness that would preclude study treatment

PRIOR CONCURRENT THERAPY:

Chemotherapy

• No concurrent chemotherapy for prostate cancer

Endocrine therapy

• No concurrent hormonal therapy for prostate cancer

Radiotherapy

• No concurrent radiotherapy for prostate cancer

Surgery

• No concurrent surgery for prostate cancer

Other

• More than 30 days since prior and no concurrent use of or prescription for fish oil or green tea supplement
• No concurrent warfarin, therapeutic anticoagulation, or other blood-thinning agents
• No concurrent treatment for prostate or other nonskin cancer
• No concurrent participation in another moderate to high-risk study