Trial Information

Prostate Cancer: Impact Of Fat And Flaxseed - Modified Diets

OBJECTIVES:

- Compare tumor proliferation in patients with newly diagnosed prostate cancer eating
fat- and/or flaxseed-modified diets.

- Compare differences in histopathological markers associated with prostate cancer (rates
of apoptosis, extent of high-grade prostatic intraepithelial neoplasia) among patients
in these diet groups.

- Compare changes in serum prostate specific antigen among patients in these diet groups.

- Compare changes in hormone-related factors (total serum testosterone and free androgen
index, insulin-like growth factor [IGF], and IGF-binding protein-3) among patients in
these diet groups.

- Compare the effects of diet on nutritional biomarkers (levels of lignans in the urine
and ejaculate, fatty acid profiles of erythrocytes and prostatic tissue) in these
patients.

- Determine associations between dietary modification and changes in dietary biomarkers,
hormonal intermediates, and study endpoints in these patients.

OUTLINE: This is a randomized study. Patients are stratified according to Gleason score
(less than 7 vs at least 7) and race (black vs non-black). Patients are randomized to 1 of 4
diet groups.

- Arm I (Flaxseed-supplemented diet): Patients are instructed to incorporate ground
flaxseed into their daily diets.

- Arm II (Low-fat diet): Patients are instructed on ways to achieve a diet with no
greater than 20% of total energy from dietary fat.

- Arm III (Flaxseed-supplemented, low-fat diet): Patients are instructed as in arm I and
arm II.

- Arm IV (Control diet): Patients are contacted weekly, but do not receive dietary
counseling until after surgery.

All patients ingest the diets for at least 3 weeks and complete diet diaries until surgery.
After surgery, all patients receive dietary counseling.

PROJECTED ACCRUAL: A total of 160 patients (40 per treatment arm) will be accrued for this
study.