Low-Fat Diet and Fish Oil in Men on Active Surveillance for Prostate Cancer

PRIMARY OBJECTIVES:

I. Determine if a 1-year low omega-6, high omega-3 fat diet combined with fish oil results in decreased prostate cancer Ki-67 index as compared to a control group in men on active surveillance.

SECONDARY OBJECTIVES:

I. Evaluate the effect of a low-fat (LF)/fish oil (FO) intervention on prostate biopsy tissue markers of progression, prostate biopsy pathologic features (Gleason grade, tumor volume ), prostate-specific antigen (PSA), and long-term clinical outcomes (clinical progression, prostate cancer therapies).

II. Evaluate potential surrogate biomarkers of proliferation (red blood cell [RBC] membrane fatty acid analyses, ex-vivo bioassay).

III. Determine if a correlation exists between free fatty acid receptor 4 (GPR120) levels and progression markers in response to the LF/FO intervention.

IV. Evaluate effect of the intervention on the National Comprehension Cancer Network (NCCN) risk group V. Evaluate compliance with a 1-year + 2 year extension LF/FO intervention. VI. Evaluate safety of a 1-year + 2-year extension LF/FO intervention.

OUTLINE: Patients are randomized to 1 of 2 arms. ARM I: Patients receive no intervention.

ARM II: Patients receive dietary counseling with a research dietitian weekly for 1 month and then monthly for 11 months. Patients are given guidelines with recommended meals to follow a high omega-3, low omega-6 diet comprising 30% kilocalories (Kcal) from fat, 15% Kcal from protein, and 65% Kcal from carbohydrates for 1 year. Patients also receive 4 fish oil capsules per day orally (PO) for 1 year.

After completion of study, patients are followed up yearly for 15 years.

Inclusion criteria

• Patients sign the informed consent
• Patient had a prostate biopsy performed by Dr. Mark with the Artemis device and has adenocarcinoma of the prostate
• Patient elects to undergo active surveillance
• Clinical stage T2c or less
• Gleason grade 3+4 or less
• PSA < 25
• Geographically able to have study visits at the University of California, Los Angeles (UCLA) Clinical Research Unit
• Subjects are willing to not consume lycopene, green tea or pomegranate supplements or pomegranate juice during the 1-year study
• If subjects are randomized to the control group they agree to not consume fish oil capsules during the 1-year study

Exclusion criteria

• Diagnostic prostate biopsy with only 1 core with cancer and < 5% of tissue from that core involved with cancer
• Patient has taken finasteride or dutasteride during the prior year
• Patient has taken fish oil during the prior 3 months
• Patient had prior treatment for prostate cancer (surgery, radiation, local ablative therapy, anti-androgen therapy or androgen deprivation therapy)
• Patient has other medical conditions that exclude him from undergoing a repeat prostate biopsy at 1-year
• Patient has allergy to fish