Joanne F. Dorgan,1 Christopher Longcope,2 Hugh E. Stephenson Jr.,3 Roni T. Falk,4 Rosetta Miller,5 Charlene Franz,2 Lisa Kahle,6 William S. Campbell,1 Joseph A. Tangrea,1 and Arthur Schatzkin1
1Division of Cancer Prevention and Control, National Cancer Institute, Bethesda, Maryland; 2Department of Obstetrics and Gynecology, University of Massachusetts Medical School, Worcester, Massachusetts; 3Department of Surgery, University of Missouri Health Sciences Center, Columbia, Missouri; 4Division of Cancer Etiology and Genetics, National Cancer Institute, Bethesda, Maryland; 5Cancer Screening Services, Ellis Fischel Cancer Center, Columbia, Missouri; 6Information Management Services, Inc., Silver Spring, Maryland
We conducted a nested case-control study to prospectively evaluate the relationship of serum estrogens and androgens to risk of breast cancer in postmenopausal women. From 1977 to 1987, 3375 postmenopausal women free of cancer and not taking replacement estrogens donated blood to the Breast Cancer Serum Bank in Columbia, Missouri. Of these, 72 were subsequently diagnosed with breast cancer. For each case, two controls matched on age and date and time of day of blood collection were selected using incidence density matching. The median age of subjects at blood collection was 62 years; the time from blood collection to diagnosis ranged from less than 1 to 9.5 years with a median of 2.9 years. Risk of breast cancer was positively and significantly associated with serum levels of estrogens and androgens. Compared to women in the lowest quartile, those in the highest quartile for non-sex hormone-binding globulin (non-SHBG) bound (bioavailable) estradiol had a relative risk of 5.2 (95% confidence interval [CI] = 1.5-18.5) and those in the highest quartile for testosterone had a relative risk of 6.2 (95% CI = 2.0-19.0). Our results lend considerable support to the hypothesis that serum concentrations of estrogens and androgens are related to the subsequent diagnosis of breast cancer in postmenopausal women. -- Environ Health Perspect 105(Suppl 3):583-585 (1997)
Key words: breast neoplasms, androgens, estrogens, epidemiology
This paper was presented in part at the Workshop on Hormones, Hormone Metabolism, Environment, and Breast Cancer held 28-29 September 1995 in New Orleans, Louisiana. Manuscript received at EHP 6 June 1996; manuscript accepted 7 August 1996.
Address correspondence to Dr. J. Dorgan, Division of Cancer Prevention and Control, National Cancer Institute, Executive Plaza North, Room 211, 6130 Executive Blvd., MSC 7326, Bethesda, MD 20892-7326. Telephone: (301) 594-2934. Fax: (301) 402-0553. E-mail: jd7g@nih.gov
Abbreviations used: CI, confidence interval; DHEAS, dehydroepiandrosterone sulfate; FSH, follicle stimulating hormone; RIA, radioimmunoassay; RR, relative risk; SHBG, sex hormone-binding globulin.
Last Update: April 10, 1997