Triple negative breast cancer

What triple negative breast cancer is

Triple negative breast cancer tests negative for all three receptors: estrogen, progesterone, and HER2. There is no hormone switch and no HER2 switch to turn off, so the medicines that do that work in other types have nothing to act on. It tends to be higher grade and to grow faster, which is exactly why it responds well to chemotherapy, which works best on fast-dividing cells. It is more common in younger women, in Black women, and in people who carry a BRCA1 gene change.

What usually happens next with triple negative breast cancer, in order

1. Genetic testing, offered to everyone with this type regardless of age or family history, because the result can change both surgery and medicine.
2. Medicine first, for most. For cancers larger than about 2 cm or with a positive node, chemotherapy comes before surgery, usually with an immunotherapy medicine, pembrolizumab, added. The course runs about five to six months. A clip is placed in the tumor first so it can be found.
3. Surgery. Lumpectomy or mastectomy, with the nodes checked. How much cancer remains is the most useful information about the future that anyone will have, and it decides the next step.
4. After surgery. If no cancer remained, immunotherapy is completed on its own. If cancer remained, an oral chemotherapy pill or, for people with a BRCA change, a PARP inhibitor is usually added for a period afterward.
5. Radiation, on the same rules as other types.

For small triple negative cancers with clear nodes, surgery may come first, followed by chemotherapy decided from the final report.

Choices you will be asked about with triple negative breast cancer

Lumpectomy or mastectomy, decided after the medicine has done its work. If a BRCA change is found, whether to remove both breasts, which is a personal decision rather than a medical necessity. Fertility preservation before chemotherapy. A clinical trial, since this is the type where the most new treatments are being studied.

Questions to bring to your appointment

These are built for triple negative breast cancer. The report decoder narrows the list further from your own report, and the print button there puts it on paper with room to write. Bring someone with you if you can; two sets of ears hear more than one.

• What is the exact type, grade, and receptor status, and can I have a copy of the report?
• What stage is it now, and what could change that after surgery?
• Should surgery come first, or medicine first, and why?
• Am I a candidate for a lumpectomy? If I chose mastectomy instead, would the outcome differ?
• How will the lymph nodes be checked, and what happens if one is positive?
• Will immunotherapy be part of my chemotherapy, and what does it add?
• Do I qualify for genetic testing, and should it be done before I decide on surgery?
• Do I need any scans of the rest of my body, and if not, why not?
• If I want to talk to a plastic surgeon before deciding, can that happen first?
• Is there a clinical trial I should know about?
• How much time do I have to decide? Is there anything that must be decided today?
• Who is my contact between appointments, and how do I reach them?
• Is there a nurse navigator or counselor I can be connected with?

Where this comes from

Published 7 September 2026 as part of the guide; a page of its own since 9 September 2026.