Evaluation of the Safety and Efficacy of Treatment w/High Dose Melphalan Given Directly Into the Liver Followed by Treatment w/Approved Cancer Treatment or Approved Cancer Treatment Alone in Patients w/ Metastatic Breast Cancer w/Liver Dominant Disease

This study is testing whether delivering a high dose of melphalan chemotherapy directly into the liver, combined with standard cancer drug therapy, can shrink tumors better than standard therapy alone in patients with metastatic breast cancer that has spread mainly to the liver. **You may be eligible if...** - You have been diagnosed with metastatic breast cancer that is HER2-negative - Your cancer has spread mainly to the liver - Your hormone receptor-positive disease has already progressed on hormone therapy and CDK 4/6 inhibitor drugs - Your cancer has been previously treated with certain antibody-drug conjugates (ADCs) or you are not eligible for those treatments **You may NOT be eligible if...** - You have severe liver disease or inadequate liver function - You are pregnant - You have had prior pelvic radiation or bone marrow transplant that limits liver treatment - Your general health is too poor for surgery-like procedures Talk to your doctor to see if this trial is right for you.