Refractory Breast Disease

When recurrence or resistance is suspected, imaging is used to locate and measure the disease, and may include CT, MRI, bone scans, or PET scanning depending on the situation. A biopsy of a new or growing area is often performed to confirm that cancer is present and to re-examine its biological features, because hormone receptor and HER2 status can change between the original tumor and a recurrence. Increasingly, detailed genetic or molecular profiling of the cancer is carried out to identify specific changes that can be matched to newer targeted treatments.

Cancer that returns is not usually re-staged using the original numbering; instead, doctors describe it by its location and extent and determine whether it is confined to one area or has spread. Disease that has reached distant organs is classified as metastatic, equivalent to stage IV, regardless of the stage at the original diagnosis. This restaging process establishes the current extent of the disease and forms the basis for selecting treatment.

Treatment for refractory and recurrent breast cancer is highly individualized and is adjusted over time as the disease responds or changes. For cancer that has spread, systemic therapies are the foundation of care, and doctors move through different options as needed. These include changing or combining hormone therapies, chemotherapy, and a growing number of targeted treatments such as CDK4/6 inhibitors for hormone receptor positive cancers, PARP inhibitors for cancers linked to inherited gene mutations, antibody-drug conjugates that deliver chemotherapy directly to cancer cells, and immunotherapy for certain tumors. Surgery or radiation therapy may still be used to control disease in a specific area, such as a local recurrence or a painful site of spread.