Tell me about biomarkers that are relevant

Breast CancerOctober 15, 2025Navis AI

Ask Navis about your situation

This answer is general. Get one about your specific case — no signup, answered right here.

or Upload your records for answers about your actual case

For informational purposes only

This answer was generated by AI grounded in NCCN guidelines and published medical literature. It is not medical advice. Always consult your oncologist or care team before making treatment decisions.

There are several important biomarkers that are relevant for breast cancer diagnosis, treatment planning, and prognosis. According to the American Cancer Society, the three main biomarkers currently used in breast cancer care are:

Hormone Receptors (ER/PR): Estrogen receptor (ER) and progesterone receptor (PR) status indicates if the cancer's growth is supported by hormones. ER/PR+ cancers can be treated with hormone therapy. About 70-80% of breast cancers are ER/PR+.
HER2 Status: Human epidermal growth factor receptor 2 (HER2) is a protein that promotes cancer cell growth. HER2+ cancers can be treated with targeted drugs. About 10-20% of breast cancers are HER2+.
Ki-67: This protein is a marker of how fast cancer cells are growing and dividing. High Ki-67 levels are associated with more aggressive cancers. This marker helps determine prognosis and treatment approach.

The NCCN Guidelines for Breast Cancer also highlight some emerging biomarkers:

PIK3CA gene mutations: May predict response to some targeted therapies
PD-L1: An immune system biomarker that may indicate potential for immunotherapy
Tumor mutational burden (TMB): High TMB may predict immunotherapy response

Multigene panel tests are also now used to analyze a range of genes to help refine prognosis and guide treatment decisions for some patients.

It's important to discuss the role of biomarker testing in your individual situation with your oncology team. Biomarker status, along with other factors like cancer stage and your overall health, help personalize treatment planning.

Ask Navis about your case

That answer is general. Ask about your specific situation — no signup, answered right here.

or Upload your records for answers about your actual case

Facing this with someone you love?

Keep the whole picture in one private place: records, a plain-language summary of where things stand, questions, and the people helping. Navis keeps it up to date so no one has to re-explain the story. Free, and only the people you invite can ever see it.

Start a care circle →