Inclusion Criteria:  Female Age criteria for pre-menopausal group: Equal to or greater than 18 years of age and less than or equal to 45 years of age. Patients of age 46-50 will be included if they have not had menstrual cessation for 12 consecutive months. Age criteria for menopausal group: At least 51 years of age (median age of menopause). Menopause is defined as cessation of menstrual cycle for 12 consecutive months. Diagnosed with ER+ breast cancer Being treated with tamoxifen (TAM) for at least 6 months CONTROL SUBJECTS: Newly diagnosed ER+ breast cancer patients of the same age group as above on TAM for 0-6 months. This criterion is based on our preliminary results showing that patients taking TAM for 6-7 months exhibit near baseline level of NETs  Exclusion Criteria:  Patient is terminal (expected survival < 6 months) Informed consent unobtainable Pregnant -The immune modulations geared toward maintenance of pregnancy are known to cause wide-spread alterations in innate and adaptive immune cell functions. In this scenario, divorcing the pregnancy-related changes in myeloid cell function from those relevant to sepsis and cancer will be complicated. History of severe congenital neutropenia due to genetic disorders, such as Kostmann Disorder (HAX1 gene mutation), ELA2 gene mutation, Wiskott-Aldrich syndrome (WAS), growth factor independent 1 protein (GFI1) gene mutation, colony stimulating factor 3 receptor (CSF3R) gene mutation, Schwachman-Diamond syndrome, Barth syndrome, warts, hypogammaglobulinemia, infections, and myelokathexis (WHIM) syndrome, and Chadiak-Higashi syndrome (this list notably does not include myelodysplastic syndrome, or acute/chronic myeloid leukemia) History of autoimmune disorders, which can affect the body's inflammatory response, such as rheumatoid arthritis, lupus, Crohn's disease, multiple sclerosis, and psoriasis. History of chronic viral infections (human immunodeficiency virus [HIV], hepatitis), which can lead to reduced or variable immune cell function. A recent positive coronavirus disease (COVID) test