Breast Stem Cells in Women at Average Risk and Increased Risk for Breast Cancer

Background: Emerging models of breast cancer suggest that breast cancers arise from a population of stem cells that are present in the normal mammary gland. The stem cell produces a clone of cancer cells. Researchers are now attempting to isolate and characterize breast stem cells and determine what events may initiate the tumorigenic process. Objectives: To identify and characterize breast stem cells from normal breast tissue from women who are free of breast cancer. To compare characteristics of breast stem cells between women at increased risk for breast cancer and women at average risk for breast cancer. To correlate breast stem cell number or characteristics with mammographic density. To establish cell cultures of breast stem cells from women at increased risk for breast cancer and women at average risk for breast cancer. Eligibility: Women who are at average or increased risk for breast cancer and over age 18 will be eligible. Design: This is a pilot tissue acquisition trial. Breast biopsies will be obtained from all subjects and breast cancer risk demographics will be collected at one time point. We aim to enroll 20 average risk and 20 increased risk women.