Research

Hormonal

Higher circulating levels of estradiol are associated with an increased risk of breast cancer in postmenopausal women (multivariate RR = 1.91; 95% CI = 1.06-3.46).

Practitioners should consider monitoring estradiol levels in postmenopausal women as a potential risk factor for breast cancer.

StrongSupportsmedium confidence
We observed statistically significant positive associations with risk of breast cancer for circulating levels of estradiol (multivariate relative risk [RR] = 1.91; 95% confidence interval [CI] = 1.06-3.46).
Susan E. Hankinson et al. · JNCI Journal of the National Cancer Institute · 1998

Why this rating

Based on the prospective evaluation within a large cohort study.

Source

Plasma Sex Steroid Hormone Levels and Risk of Breast Cancer in Postmenopausal Women

Susan E. Hankinson et al. · JNCI Journal of the National Cancer Institute · 1998

DOI 10.1093/jnci/90.17.1292

case_control · n=11169Cited 690×
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DOI resolved against Crossref · corpus check 2026-06-10

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