Effect of Dietary Soy on Estrogens in Breast Fluid, Blood, and Urine Samples From Healthy Women
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ClinicalTrials.gov Identifier: NCT00513916 |
Recruitment Status :
Completed
First Posted : August 9, 2007
Last Update Posted : December 19, 2013
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RATIONALE: Chemoprevention is the use of certain drugs to keep cancer from forming. Eating a diet high in isoflavones, compounds found in soy foods, may keep cancer from forming.
PURPOSE: This randomized phase III trial is studying the effects of dietary soy on estrogens in breast fluid, blood, and urine samples from healthy women.
Condition or disease | Intervention/treatment | Phase |
---|---|---|
Breast Cancer Healthy, no Evidence of Disease | Dietary Supplement: soy isoflavones | Phase 3 |
OBJECTIVES:
- Examine the effects of two daily servings of soy on estrogen levels in nipple aspirate fluid (NAF) and serum.
- Investigate cytologic patterns of epithelial breast cells obtained from NAF as a measure of proliferation in relation to soy intake.
- Explore the effect of two daily servings of soy on cytochrome alterations of estrogen metabolism as expressed in the formation of urinary 2-, 16α-, and 4-hydroxy estrogen metabolites.
- Compare estrogen levels in NAF and serum measured at the same time during the luteal phase.
OUTLINE: This is a multicenter study. Participants are randomized to 1 of 2 intervention arms.
- Arm I: Participants partake in a high soy diet consisting of 2 daily soy servings (approximately 50mg isoflavones). The choice of soy foods will include ½ cup of tofu, ¾ cup of soy milk, or ¼ cup of soy nuts. Replacement of currently consumed foods with soy foods will be encouraged.
- Arm II: Participants will be asked to keep their soy intake below 3 servings per week. The participants will also receive general nutrition counseling.
In both arms, intervention continues for 6 months. After 6 months, participants undergo a 1-month washout period and then cross-over to the other intervention arm.
Nipple aspirate fluid, urine, and blood samples are collected periodically to measure laboratory endpoints.
Study Type : | Interventional (Clinical Trial) |
Estimated Enrollment : | 100 participants |
Allocation: | Randomized |
Primary Purpose: | Prevention |
Official Title: | Effects of Soy on Estrogens in Breast Fluid and Urine |
Study Start Date : | July 2006 |
Actual Primary Completion Date : | February 2011 |
Actual Study Completion Date : | February 2012 |

Arm | Intervention/treatment |
---|---|
Experimental: Arm I
Participants partake in a high soy diet consisting of 2 daily soy servings (approximately 50mg isoflavones). The choice of soy foods will include ½ cup of tofu, ¾ cup of soy milk, or ¼ cup of soy nuts. Replacement of currently consumed foods with soy foods will be encouraged. |
Dietary Supplement: soy isoflavones
High or low dose of soy isoflavones in the diet. |
Active Comparator: Arm II
Participants will be asked to keep their soy intake below 3 servings per week. The participants will also receive general nutrition counseling.
|
Dietary Supplement: soy isoflavones
High or low dose of soy isoflavones in the diet. |
- Effect of two daily servings of soy on estrogen levels in nipple aspirate fluid (NAF) and serum
- Cytologic patterns of epithelial breast cells obtained from NAF
- Effect of two daily servings of soy on cytochrome alterations of estrogen metabolism as expressed in the formation of urinary 2-, 16α-, and 4-hydroxy estrogen metabolites
- Comparison of estrogen levels in NAF and serum measured at the same time during luteal phase

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Ages Eligible for Study: | 30 Years to 45 Years (Adult) |
Sexes Eligible for Study: | Female |
Accepts Healthy Volunteers: | Yes |
DISEASE CHARACTERISTICS:
-
Healthy participant
- No diagnosis of cancer
PATIENT CHARACTERISTICS:
- Premenopausal
- Regular menstrual cycles
PRIOR CONCURRENT THERAPY:
- Not taking birth control pills or other hormones

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT00513916
United States, Hawaii | |
Cancer Research Center of Hawaii | |
Honolulu, Hawaii, United States, 96813 |
Study Chair: | Gertraud Maskarinec, MD, PhD | University of Hawaii Cancer Research Center |
Publications automatically indexed to this study by ClinicalTrials.gov Identifier (NCT Number):
Responsible Party: | Gertraud Maskarinec, Cancer Research Center of Hawaii |
ClinicalTrials.gov Identifier: | NCT00513916 |
Other Study ID Numbers: |
CDR0000560821 UHM-CHS-4116 |
First Posted: | August 9, 2007 Key Record Dates |
Last Update Posted: | December 19, 2013 |
Last Verified: | April 2009 |
breast cancer healthy, no evidence of disease |
Breast Neoplasms Neoplasms by Site Neoplasms Breast Diseases Skin Diseases |