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Racial/ethnic differences in postmenopausal endogenous hormones: the multiethnic cohort study
Veronica Wendy Setiawan1, Christopher A Haiman, Frank Z Stanczyk
1Department of Preventive Medicine, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA. vsetiawa@usc.edu
Summary
Ethnic differences in hormone levels influence breast cancer risk in postmenopausal women. Native Hawaiians showed higher estrogen and testosterone, and lower SHBG, correlating with higher breast cancer incidence.
Area of Science:
- Endocrinology
- Oncology
- Epidemiology
Background:
- Postmenopausal women with higher estrogen and lower sex hormone-binding globulin (SHBG) face increased breast cancer risk.
- Breast cancer incidence varies significantly across ethnic groups, suggesting a role for endogenous hormones.
Purpose of the Study:
- To investigate ethnic variations in endogenous sex hormone profiles among postmenopausal women.
- To explore the association between hormone levels and breast cancer incidence across different racial/ethnic groups.
Main Methods:
- Measured plasma concentrations of androstenedione, testosterone, estrone (E(1)), estradiol (E(2)), and SHBG in 739 postmenopausal women from the Multiethnic Cohort Study.
- Included African Americans, Native Hawaiians, Japanese Americans, Latinas, and Whites.
- Adjusted for age, breast cancer risk factors, and lifestyle factors.
Main Results:
- Significant variations in mean testosterone, estrogen, and SHBG levels were observed across populations.
- Native Hawaiians exhibited the highest androstenedione, testosterone, and estrogen levels, alongside the lowest SHBG.
- Compared to Whites, Native Hawaiians showed significantly higher androgens and estrogens, and lower SHBG, aligning with breast cancer incidence patterns.
Conclusions:
- Endogenous hormone profiles differ significantly across racial/ethnic groups of postmenopausal women.
- These hormonal variations are consistent with observed ethnic disparities in breast cancer incidence.
- Hormonal milieu plays a crucial role in understanding ethnic differences in breast cancer risk.
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