Low-Fat Fish Oil Diet for Prostate Cancer Prevention

May 3, 2019 updated by: Jonsson Comprehensive Cancer Center

Comparison Study of a Low-Fat Diet Supplemented With Fish Oil and a Standard Western Diet in Individuals With Prostate Cancer

Studies on patterns of how many men get prostate cancer in other countries show that environment contributes to the high incidence of prostate cancer in the United States. Epidemiology studies suggest that this influence may be reduced by the diet of men at risk of getting prostate cancer. Although the exact nature of the effects of diet are not completely known, the amount of fat eaten appears to affect the number of men who get prostate cancer. The type of fat also seems to matter. Eating more of a type of fat called omega-3 polyunsaturated fat is associated with decreased prostate cancer risk. Omega-3 fat comes from fish and is quite different from the type of fat from animals and vegetables (omega-6 fat). Because the exact mechanism of this reduction in prostate cancer risk is not known, no blood test indications, called markers, have been discovered that would show the effect working.

Study doctors designed this study to try to find markers in the blood tests of men who have prostate cancer, and to find out if a diet supplemented with omega-3 type fat from fish oil helps reduce those markers, hence indicating that it helps reduce the cancer in these men. These men will be compared to men with prostate cancer whose diets do not contain the fish-oil fat.

The men chosen will have prostate cancer and be scheduled for operations to have their prostate glands removed. They will be chosen randomly to be given the fish-oil diet or a regular Western diet for comparison for 4 to 8 weeks. Their blood will be checked at the beginning of the diet. After the 4-to-8-week period, they will have their operations. Their blood will be checked again and a sample of their removed prostate will be examined to tell if the diet had any effect on the cancer and its markers.

Study Overview

Status

Completed

Conditions

Intervention / Treatment

Detailed Description

  1. To establish and validate intermediate biomarkers for prostate cancer prevention trials by conducting a dietary intervention trial of a low-fat diet with omega-3 fatty acid supplements in men undergoing radical prostatectomy. In initial trials it was feasible to intervene with diet and obtain tissue and serum for bioassay and biomarker development. This aim is to study the effect a low-fat, high omega-3 diet has on serum and tissue biomarkers from patients who have prostatectomies for prostate cancer. Ultimately, we hope to identify and validate intermediate markers of efficacy for large-scale dietary prevention trials.
  2. To establish and validate insulin growth factor-1 (IGF-1) and insulin growth factor binding proteins (IGFBP) as relevant intermediate biomarkers for prostate cancer prevention trials. IGF-1 is a peptide growth factor that is important to the growth and progression of prostate cancer. To our knowledge, no prospective dietary intervention studies have evaluated the effect of a low-fat diet with omega-3 fatty acid supplements on IGF-1 and IGFBPs, and their potential to serve as relevant intermediate markers for low-fat dietary intervention trials for prostate cancer prevention.
  3. To establish and validate serum and tissue fatty acids as relevant intermediate biomarkers for prostate cancer prevention trials. We will evaluate if men randomized to a low-fat, fish-oil-supplemented diet have increased serum ratios of omega-3:omega-6 fatty acids compared with men randomized to a control Western diet before radical prostatectomy. We also will study if patients in the low-fat, fish oil arm have increased ratios of membrane omega-3:omega-6 fatty acids as well as decreased COX-2 and decreased PGE-2 levels in benign and malignant tissue and in visceral fat. If so, it will proved further evidence to support the potential of low-fat fish oil diets for prostate cancer prevention. If serum omega-3:omega-6 ratios correlate with changes in COX-2 and PGE-2 in tissues, then serum omea-3:omega-6 ratios may be useful for monitoring activity and efficacy of low-fat fish-oil-supplemented diets in future trials.

Study Type

Interventional

Enrollment (Actual)

56

Phase

  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

  • United States
    • California
      • Los Angeles, California, United States, 90095
        • UCLA Jonsson Comprehensive Cancer Center
      • Los Angeles, California, United States, 90073
        • West Los Angeles VA

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

40 years to 75 years (Adult, Older Adult)

Accepts Healthy Volunteers

No

Genders Eligible for Study

Male

Description

Eligibility Criteria:

  • Patient consents to participate.
  • Medically able to receive and comply with the diet.
  • Lives near enough for counseling and follow-up.
  • Has elected to have operation to remove prostate.
  • Agrees to stop diet or vitamin supplements or herbal supplements for 1 week before the study begins.
  • Patient able to stop taking aspirin, COX-2 inhibitors, and other anti-inflammatory medications for 1 week before study start.
  • Patient able to safely stop taking fish oil capsules 2 weeks before the diet starts.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Diagnostic
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Placebo Comparator: Standard Western Diet
Subjects will be asked to consume a standard Western Diet for 4 weeks. For the 4-week period, subjects will be provided with all food and beverages. Subjects will also undergo a medical examination, dietary interview, blood draw, and radical prostatectomy(as part of standard of care).
Dietary supplement: Western Diet
Subjects will be provided with a standard western diet, food and beverages, to consume during their 4 week participation in this study.
Other: Medical Examination
Subjects will have a routine medical exam.
Other: Dietary Interview
Subjects will meet with the study nutritionist and have their current diet evaluated. Subjects will also undergo a test (bioimpedance) to estimate their body fat, lean weight, and the rate at which their body burns fat.
Other: Blood Draw
40 mL of blood will be drawn from subjects to measure PSA, fatty acids, insulin and various hormones.
Procedure: Radical Prostatectomy
Subjects will undergo a radical prostatectomy as part of their standard of care.
Experimental: Low-Fat Diet
Subjects will be asked to consume a low fat diet with fish oil and vitamin E supplements for 4 weeks. For the 4-week period, subjects will be provided with all food and beverages. Subjects will also undergo a medical examination, dietary interview, blood draw, and radical prostatectomy(as part of standard of care).
Other: Medical Examination
Subjects will have a routine medical exam.
Other: Dietary Interview
Subjects will meet with the study nutritionist and have their current diet evaluated. Subjects will also undergo a test (bioimpedance) to estimate their body fat, lean weight, and the rate at which their body burns fat.
Other: Blood Draw
40 mL of blood will be drawn from subjects to measure PSA, fatty acids, insulin and various hormones.
Procedure: Radical Prostatectomy
Subjects will undergo a radical prostatectomy as part of their standard of care.
Dietary supplement: Fish Oil
Subjects will be asked to take 10 grams of fish oil per day for 4 weeks.
Dietary supplement: Vitamin E supplement
Subjects will be asked to take 800 International Units per day of Vitamin E for 4 weeks.
Dietary supplement: Low-Fat Diet
Subjects will be provided with a low-fat diet (food and beverages) for their 4 week participation in this study.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Time Frame
check for insulin growth factor-1 (IGF-1) and insulin growth factor binding proteins (IGFBP) as relevant intermediate biomarkers for prostate cancer
Time Frame: 4 weeks
4 weeks

Secondary Outcome Measures

Outcome Measure
Time Frame
Check serum and tissue fatty acids as relevant intermediate biomarkers for prostate cancer
Time Frame: 4 weeks
4 weeks

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Jonsson Comprehensive Cancer Center

Collaborators

National Cancer Institute (NCI)

Investigators

  • Principal Investigator: William Aronson, MD, UCLA and Western Los Angles VA

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

General Publications

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

December 18, 2001

Primary Completion (Actual)

February 12, 2018

Study Completion (Actual)

February 12, 2018

Study Registration Dates

First Submitted

November 25, 2008

First Submitted That Met QC Criteria

November 25, 2008

First Posted (Estimate)

November 26, 2008

Study Record Updates

Last Update Posted (Actual)

May 7, 2019

Last Update Submitted That Met QC Criteria

May 3, 2019

Last Verified

May 1, 2019

More Information

Terms related to this study

Additional Relevant MeSH Terms

Other Study ID Numbers

  • 01-07-026
  • P50CA092131-01A1 (U.S. NIH Grant/Contract)
  • 11-002610 (Other Identifier: JCCC)

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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