Treatment of Triple-negative Breast Cancer

In triple-negative breast cancer (TNBC), the cancer cells do not have estrogen or progesterone receptors. They also do not have high levels of the HER2 protein. Because of this, hormone therapy and HER2-targeted drugs are not helpful for TNBC.

Chemotherapy (chemo) is the main systemic treatment for this type of breast cancer. Immunotherapy and antibody-drug conjugates are now also available and have expanded treatment options in recent years.

TNBC can be more challenging to treat than some other breast cancer types because fewer targeted therapies are available. However, it often responds well to chemotherapy. Many people with early-stage TNBC do very well, especially if the cancer is gone after treatments that are given before surgery.

Stages I-III triple-negative breast cancer

If your triple-negative breast cancer is stage I-III, you might get:

• Surgery first, possibly followed by other treatments
• Surgery after other treatments (chemo with or without immunotherapy)

Surgery first

If the early-stage TNBC tumor is small enough to be removed with surgery, you might first have breast-conserving surgery or a mastectomy. This will include checking your lymph nodes.

Radiation: Radiation may follow surgery in certain cases. For example, you might need radiation after surgery if your tumor is large or if your lymph nodes are found to have cancer.

Chemo: You might also get chemo after surgery. This is called adjuvant chemotherapy. It could lower the chances of the cancer coming back.

Targeted therapy after chemo: Some people might take the targeted drug olaparib (Lynparza) for a year after adjuvant chemo. This may be given to people with a BRCA mutation who are found during surgery to have:

• A tumor larger than 2 cm but no bigger than 5 cm OR
• 1 to 3 axillary (underarm) lymph nodes with cancer

When olaparib is given this way, it can help some people live longer.

Surgery after other treatments

Chemo is often given before surgery. This is called neoadjuvant chemotherapy. It can be given by itself or with pembrolizumab (Keytruda) to shrink a large tumor and/or lymph nodes with cancer.

If you get chemo before surgery and the surgeon still finds cancer in the tissue they remove, your cancer care team may recommend:

• An oral chemo medicine called capecitabine (Xeloda) for 18 to 24 weeks. This might help some people live longer.
• More pembrolizumab after surgery to reduce the chances of the cancer coming back.
• The targeted drug olaparib for 1 year for people with a BRCA mutation. This may lower the chance of the cancer recurring. When given this way, it can help some people live longer. 

Stage IV triple-negative breast cancer

When TNBC has spread to other parts of your body, your treatment will depend on:

• Whether the cancer cells make a protein called PD-L1
• Whether you’ve already received certain treatments

About 1 in 5 TNBCs are PD-L1 positive, meaning the cancer cells make the PD-L1 protein.

See Treatment of Stage IV (Metastatic) Breast Cancer for more information.

Recurrent triple-negative breast cancer

If TNBC comes back (recurs) locally, cannot be removed with surgery, and makes the PD-L1 protein, two options are:

• Sacituzumab govitecan (Trodelvy) plus pembrolizumab
• Pembrolizumab plus chemotherapy

Other treatments might be options as well, depending on the situation.

If the cancer recurs in other parts of the body, options may include chemotherapy, sacituzumab govitecan (Trodelvy), or other treatments based on the features of the cancer.

Considering a clinical trial

No matter what stage of TNBC you have, participating in a clinical trial of new treatments is also a good option.

TNBC is uncommon, and it can be more challenging to treat than some other types of breast cancer. Clinical trials often give you access to medicines not available for standard treatment.