Circulating Fetal Cells and Breast Cancer

After pregnancy, fetal cells remain in a woman's body for years. These cells may be involved in different physiological situations (e.g. wound healing) and diseases (e.g. cancer).The study will evaluate the level of circulating fetal immune cells in patients with breast cancer vs controls with benign breast tumors, and further characterize these fetal cells. Patients participation will be limited to accepting that an additional blood sample is collected on the day of their preop consultation and blood test.