In a study of predominantly premenopausal women, higher serum levels of the adrenal androgens DHEA and DHEAS were linked with an increased risk of breast cancer among women over the age of 45. These results were published in the journal Cancer Epidemiology, Biomarkers, and Prevention.
Many breast cancers are hormone responsive, prompting interest in the relationship between serum levels of hormones such as estrogen and the risk of breast cancer.
DHEA and DHEAS are hormones produced by the adrenal gland. They are androgen and estrogen precursors, and can also produce independent effects by binding to androgen receptors.
While the basis for a link between these hormones and breast cancer is poorly understood, women with higher serum levels of DHEA and DHEAS appear to have an increased risk of postmenopausal breast cancer. In younger women, results have been less consistent.
To explore the relationship between serum levels of DHEA and DHEAS and risk of premenopausal breast cancer, researchers evaluated information from the Nurses’ Health Study II. This study enrolled more then 100,000 female nurses who were between the ages of 25 and 42 when the study began in 1989. Blood samples were collected from a sample of 29,611 of the study participants.
Of the women who provided blood samples, 317 subsequently developed breast cancer. Serum levels of DHEA and DHEAS in these women were compared to levels in 636 women without breast cancer.
- Overall, level of DHEA or DHEAS did not differ between women with or without breast cancer.
- Women with higher levels of DHEA or DHEAS did have an increased risk of estrogen receptor-positive and progesterone receptor-positive breast cancer. Women with the highest levels of DHEAS had a 90% increased risk of this type of cancer.
- Age also influenced the link between DHEA and DHEAS and breast cancer risk. Among women under the age of 45, there was no link between level of DHEA or DHEAS and risk of breast cancer. Among women age 45 or older, those with the highest levels of DHEA or DHEAS had an increased risk of breast cancer.
These results suggest a link between adrenal androgens and breast cancer risk in certain subgroups of premenopausal women. Higher serum levels of adrenal androgens increased breast cancer risk in women over the age of 45, and were most strongly linked with estrogen receptor-positive and progesterone receptor-positive breast cancer.
Reference: Tworoger SS, Missmer SA, Eliassen AH et al. The Association of Plasma DHEA and DHEA Sulfate with Breast Cancer Risk in Predominantly Premenopausal Women. Cancer Epidemiology, Biomarkers, and Prevention. 2006;15:967-71.