Patients who have been diagnosed with breast cancer and have undergone Guardant360 testing will be approached regarding participation in the study. After being informed about the study and potential risks, all patients providing informed consent and access to their medical records, will provide a list of their health care providers related to their cancer treatment. Data related to their routine clinical care will be abstracted from medical records.
The purpose of this study is to observe the routine clinical care of patients who have been diagnosed with breast cancer and have undergone Guardant360 testing.