Premenopausal Hormone Concentrations in a Population of Women at Very Low Risk of Breast Cancer

Background:

• Incidence of breast cancer is very low in Mongolia (6.6/100,000), especially in rural areas. Over the past 15 years, there has been considerable economic growth in Mongolia, resulting in migration to urban centers such as the capital, Ulaanbaatar, from areas with nomadic or semi-nomadic lifestyles. This recent migration offers an opportunity to study the endocrine profiles of premenopausal women as they acculturate to a more Western lifestyle. Objectives:
• To obtain new data on premenopausal endocrine and growth factor concentrations to assess possible variations by migration status within Ulaanbaatar; that is, to compare women who have been living in Ulaanbaatar for the longest period of time with those who have recently moved to Ulaanbaatar.
• To compare data from Mongolia with data from the United States (and possibly China), where women are at higher risk of breast cancer. Eligibility:
• A sample of 375 premenopausal women will be drawn from a larger sample of mothers whose children are participating in a study conducted by Harvard Medical School. Only mothers of girls will be included in this cross-sectional study. Women ages 25 44 years who are not pregnant or breastfeeding are eligible. Design:
• A total of 30 ml (three 10 ml samples) of whole blood will be collected. Women will be asked to provide a spot urine sample. These samples will be sent periodically to the NCI biorespository during the course of the study for testing. A portion of a sample for each participant will be kept in Ulaanbaatar in case of problems in delivery to the United States.
• The following hormones will be evaluated: testosterone, androstenedione, dehydroepiandrosterone (DHEA), DHEA-sulfate, estrone, estradiol, estriol, progesterone, prolactin, placental lactogen, IGF-1 and IGFBP-3, VEGF, soluble endoglin, and possibly other angiogenic proteins.
• Socioeconomic status and medical and lifestyle information will be assessed by questionnaire, including ethnicity, occupation, education, and migration status (e.g., whether she moved from a rural area and time since migration). Breast cancer risk factors such as age at first pregnancy, age at first menstruation, gravidity (total number of pregnancies), parity (total number of childbirths), smoking status, alcohol use, and dietary intake will also be determined. (These questionnaires will have been pilot tested and revised before the start of this study.) The Global Physical Activity Questionnaire, developed by the World Health Organization, will assess physical activity.
• Mean and median premenopausal hormone concentrations of previously collected blood samples from women in the United States who are at high breast cancer risk will be compared with the Mongolian samples. In addition, Chinese data will be compared if available.