Sex hormone levels in serum in relation to the development of breast cancer.

In 1974, approximately 13,000 female residents of Washington County, Maryland, donated 15 ml of blood as part of a project to determine if certain serologic factors were related to the development of site-specific cancer. Sera were stored at -73 C. The present study reports the associations of serum levels of estrone, estradiol, estriol, androstenedione, progesterone, and testosterone with breast cancer among 17 premenopausal cases diagnosed 8-132 months after blood was drawn, and 39 postmenopausal cases diagnosed 6-72 months after blood was drawn. Each case was matched to four controls selected from the other serum bank donors. Matching factors were age, race, and time since last menstrual period. Cases and controls who were taking estrogen-containing preparations were excluded from this analysis. Sera were analyzed without knowledge of case-control status. Differences in levels of serum hormones between cases and controls were slight and not statistically significant.