Clinical trial NCT00204490: Soy Isoflavones and Breast Cancer Risk Reduction
Official title: Mammographic Density and Soy Isoflavones
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: PHASE2
Conditions: Breast Cancer
Keywords: soy
isoflavones
phytoestrogens
prevention
mammographic density
bone density
Lead sponsor: The University of Texas Medical Branch, Galveston
Sponsor class: OTHER
Collaborators: name: National Cancer Institute (NCI)
name: National Center for Research Resources (NCRR)
First posted: 2005-09-20
Enrollment: 197
Sex: FEMALE
Minimum age (years): 30
Maximum age (years): 42
Standard ages: ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: PARALLEL
Intervention model description: One group received soy isoflavones (60 mg daidzein, 60 mg gensitein and 16.6 mg glycitein, all as aglycone equivalent) Another group, carbohydrate filler
Primary purpose: TREATMENT

Brief summary: Soy consumption has been associated with reduced risk for developing breast cancer. Soy contains isoflavones which are weak estrogens. The roles of soy isoflavones in reducing breast cancer risk are currently unclear. Breast density has been considered as a breast cancer risk marker. We hypothesize that because isoflavones have estrogen-like activities, breast density and possibly bone density will be lower in women on soy-isoflavones.

Detailed description: This is a randomized, double-blind study, with two arms and 100 women in each arm. Premenopausal women will be recruited and randomly allocated to take one of the two different dietary supplements in pills daily for 2 years. The two supplements are soy isoflavones (treatment) and placebo (carbohydrates). Both treatment and placebo pills will contain multi-vitamins and minerals. Multiple blood, urine, and breast fluid samples will be obtained before and during the dietary supplement periods and analyzed for biomarkers of breast cancer risk. At baseline and after the intervention period, breast density and bone density will be assessed by radiologic techniques. The efficacy of the dietary intervention will be determined by comparing mean changes of serum markers for breast cancer risk,dense breast tissue, and bone mineral density over the two year dietary intervention period in the two supplement groups with adjustment for baseline values and individual patient characteristics of interest. We predict that 2 years of soy isoflavone supplement will reduce breast density, which may be explained by individual changes in serum markers of breast cancer risk.

Eligibility criteria: Inclusion Criteria:

* healthy premenopausal women
* 30 to 42 years old
* normal mammograms
* regular menstrual cycles

Exclusion Criteria:

* abnormal mammograms
* first degree relatives with breast cancer
* pregnant or lactating
* peri- or post-menopause
* breast augmentation, reduction or lifting
* on oral contraceptive medications or exogenous hormones
* medically prescribed diets
* allergic reaction to soy products

Primary outcomes:
measure: Fibroglandular Tissue in Total Breast (FGBT%)
timeFrame: baseline, and after year 1 and 2 of supplementation
measure: Breast Density by Mammography
timeFrame: baseline, and after year 1 and 2 of supplementation
Secondary outcomes:
measure: Bone Mineral Density
timeFrame: one and two years after dietary supplement
Other outcomes:
Locations:
city: Galveston
country: United States
facility: General Clinical Reserach Center, The University of Texas Medical Branch
state: Texas
Study officials:
affiliation: The University of Teas Medical Branch
name: Lee-Jane W Lu, Ph.D.
role: PRINCIPAL_INVESTIGATOR
References:
citation: Lu LW, Chen NW, Nayeem F, Nagamani M, Anderson KE. Soy isoflavones interact with calcium and contribute to blood pressure homeostasis in women: a randomized, double-blind, placebo controlled trial. Eur J Nutr. 2020 Sep;59(6):2369-2381. doi: 10.1007/s00394-019-02085-3. Epub 2019 Sep 18.
citation: Lu LW, Chen NW, Nayeem F, Ramanujam VS, Kuo YF, Brunder DG, Nagamani M, Anderson KE. Novel effects of phytoestrogenic soy isoflavones on serum calcium and chloride in premenopausal women: A 2-year double-blind, randomized, placebo-controlled study. Clin Nutr. 2018 Dec;37(6 Pt A):1862-1870. doi: 10.1016/j.clnu.2017.11.002. Epub 2017 Nov 11.
citation: Lu LJ, Nishino TK, Johnson RF, Nayeem F, Brunder DG, Ju H, Leonard MH, Grady JJ, Khamapirad T. Comparison of breast tissue measurements using magnetic resonance imaging, digital mammography and a mathematical algorithm. Phys Med Biol. 2012 Nov 7;57(21):6903-27. doi: 10.1088/0031-9155/57/21/6903. Epub 2012 Oct 9.