Environment and Breast Cancer: Science Review
About
Urinary phytoestrogen excretion and breast cancer risk: evaluating potential effect modifiers endogenous estrogens and anthropometrics
Dai, Q., Franke, A. A., Yu, H., Shu, X. O., Jin, F., Hebert, J. R., Custer, L. J., Gao, Y. T., Zheng, W. Cancer Epidemiology, Biomarkers & Prevention. 2003. 12:6, 497-502.
Topic area
Body size
Body size
Study design
other: case-control
other: case-control
Funding agency
NCI
NCI
Study Participants
Number of Cases
117
117
Menopausal Status
The menopausal status of women included in this study is listed here.
Post menopausal
Number of Controls
controls: 117
controls: 117
Participant selection: Inclusion and exclusion criteria
Criteria used to select participants in the study.
Parent study: Shanghi Breast Cancer Study.
In: resident of urban Shanghai, China between 1996 and 1998; age 25 to 64 at baseline; women whose blood and urine samples were taken before before cancer treatment (cases); postmenopausal women; women who participated in both estrogen and phytoestrogen studies
Ex: women whose urine samples were not available for the phytoestrogen study
Comment about participation selection
Strengths: Anthropometric data measured by trained nurses; technicians who performed assays were unaware of any information on study subjects; analyzed phytoestrogen excretion rates in relation to breast cancer, stratified by levels of BMI and W/H ratio; urine samples of the cases were taken before any cancer therapy; Limitations: study used post-diagnostic samples which could allow for bias if women changed their diet after being diagnosed with breast cancer; sample size was small; statistical power for evaluating interaction was limited
Strengths: Anthropometric data measured by trained nurses; technicians who performed assays were unaware of any information on study subjects; analyzed phytoestrogen excretion rates in relation to breast cancer, stratified by levels of BMI and W/H ratio; urine samples of the cases were taken before any cancer therapy; Limitations: study used post-diagnostic samples which could allow for bias if women changed their diet after being diagnosed with breast cancer; sample size was small; statistical power for evaluating interaction was limited
Exposures investigated
BMI and W/H ratio
BMI and W/H ratio
How exposure was measured
Questionnaire, in person Anthropometric measurement, researcher-administered
Questionnaire, in person Anthropometric measurement, researcher-administered
Breast cancer outcome investigated
Primary breast cancer
Primary breast cancer
Ethnic groups with separate analysis
If this study provided a separate analysis by ethnic or racial group, the groups are listed here.
Chinese
Confounders considered
Other breast cancer risk factors, such as family history, age at first birth, and hormone replacement therapy use, that were taken into account in the study.
Adequately controlled, Confounders: age at first live birth, ever diagnosed with fibroadenoma, total meat intake, physical activity and BMI
Genetic characterization included
If the study analyzed relationships between environmental factors and inherited genetic variations, this field will be marked “Yes.” “No”, if not.
No
Description of major analysis
Effect Modifiers: excretion rate of isoflavonoids
Effect Modifiers: excretion rate of isoflavonoids
Strength of associations reported
Association between postmenopausal breast cancer risk and women with a high urinary phytoestrogen excretion rate of isoflavonoids, OR=0.46(0.22-0.95) trend p=0.04
Association between postmenopausal breast cancer risk and women with a high urinary phytoestrogen excretion rate of isoflavonoids who have a BMI of 25 or greater, OR=0.38(0.13-1.17) trend p=0.06
Association between postmenopausal breast cancer risk and women with a high urinary phytoestrogen excretion rate of isoflavonoids who have a WHR of 0.84 or greater, OR=0.18(0.05-0.68) trend p=0.02
Association between postmenopausal breast cancer risk and women with a high urinary phytoestrogen excretion rate of lignans, OR=0.50(0.23-1.10) trend p=0.09
Association between postmenopausal breast cancer risk and women with a high urinary phytoestrogen excretion rate of lignans who have a BMI of 25 or greater, OR=0.27(0.07-1.10) trend p=0.08
Association between postmenopausal breast cancer risk and women with a high urinary phytoestrogen excretion rate of lignans who have a WHR of 0.84 or greater, OR=0.17(0.04-0.71) trend p=0.02
Association between postmenopausal breast cancer risk and women with a high urinary phytoestrogen excretion rate of isoflavonoids, OR=0.46(0.22-0.95) trend p=0.04
Association between postmenopausal breast cancer risk and women with a high urinary phytoestrogen excretion rate of isoflavonoids who have a BMI of 25 or greater, OR=0.38(0.13-1.17) trend p=0.06
Association between postmenopausal breast cancer risk and women with a high urinary phytoestrogen excretion rate of isoflavonoids who have a WHR of 0.84 or greater, OR=0.18(0.05-0.68) trend p=0.02
Association between postmenopausal breast cancer risk and women with a high urinary phytoestrogen excretion rate of lignans, OR=0.50(0.23-1.10) trend p=0.09
Association between postmenopausal breast cancer risk and women with a high urinary phytoestrogen excretion rate of lignans who have a BMI of 25 or greater, OR=0.27(0.07-1.10) trend p=0.08
Association between postmenopausal breast cancer risk and women with a high urinary phytoestrogen excretion rate of lignans who have a WHR of 0.84 or greater, OR=0.17(0.04-0.71) trend p=0.02
Author address
Department of Medicine and Vanderbilt-Ingram Cancer Center, Vanderbilt University, Nashville, Tennessee 37232-8300, USA.
Department of Medicine and Vanderbilt-Ingram Cancer Center, Vanderbilt University, Nashville, Tennessee 37232-8300, USA.
Controls participation rate
Greater than 70%
Greater than 70%