Oral Aromatase Inhibitors Modify the Gut Microbiome Effecting Estrogen Bioavailability
The purpose of this research is to study the bacteria in participants' gut before receiving a medicine called an aromatase inhibitor for breast cancer and after participants receive medicine for breast cancer.
• Pathologic diagnosis in situ or invasive breast cancer for which initiating aromatase inhibitors therapy is recommended or initiating aromatase inhibitors for risk reduction.
• ECOG performance status 0,1, 2, 3.
• Age ≥ 18 years
• HER2+ breast cancer is allowed if patients are on a monoclonal antibody therapy for which a change is not anticipated while on study (12 weeks) and they have been on the monoclonal antibody therapy for at least 4 weeks.
• Ability to read, understand and evaluate study materials and willingness to sign a written informed consent document.