PLEASE READ: This study is designed for patients with metastatic (stage IV) breast cancer (any subtype). The study in particular is interested in splicesome mutations, in particular SF3B1. If you have this mutation, it should be written on your report. If you do not have metastatic breast cancer and the SF3B1 mutation, the tumor board will not formally review your records, however, you will receive an automated email with general information about select mutations if applicable.