A Pilot Study of a Micro-Organosphere Drug Screen Platform to Lead Care in Advanced Breast Cancer

The purpose of this study is to determine the feasibility of generating sufficient patient derived micro-organospheres (PDMO) from a biopsy of a patient's advanced breast cancer to determine sensitivity to the most common forms of chemotherapy used in advanced breast cancer care. While subjects are on study, they will first receive a standard of care clinical biopsy from which extra tissue is taken for research purposes. Following the biopsy, a PDMO will be generated and they will receive a chemotherapy regimen as determined by their treating physician. This study aims to enroll 15 patients. Of this 15 patient cohort we aim to enroll 5 patients with estrogen receptor positive (ER+)/human epidermal growth factor receptor 2 negative (HER2-) disease, 5 patients with ER+/HER2+ or ER-/HER2+ disease, and 5 patients with ER-/HER2- (TNBC) disease. There are risks to having biopsies and blood draws that may include moderate bleeding and pain at the biopsy site.