Doctors do not know which women treated for early-stage estrogen receptor-positive (ER+) breast cancer will have their cancer come back in their breast or spread to other parts of their body. The purpose of this study is to collect information from women who have been diagnosed with ER+ breast cancer in order to learn which factors increase or decrease the risk of having a recurrence.
If you are eligible and agree to participate in this study, you will be asked to complete 6 online questionnaires over the course of 5 years. Each questionnaire will take about 1 hour and will ask about your medical history, breast cancer history and treatment, lifestyle, and habits. The questionnaires are available in English.