Triple-Negative Breast Cancer (TNBC)

Medically Reviewed by Dany Paul Baby, MD on April 29, 2022
6 min read

Triple-negative breast cancer is any cancer that tests negative for three of the main things -- the hormones estrogen and progesterone and a protein called HER2 -- that drive other forms of the disease. Knowing that helps doctors figure out how to best treat you.

That’s important because triple-negative breast cancer is more aggressive than other forms. It’s more likely to have spread beyond your breast at the time it’s found, and there’s a higher chance it will come back within the first 3 years after treatment. It’s also more likely to be fatal within the first 5 years. But once you pass those milestones, your odds of beating it are about the same as someone with any other type of breast cancer.

One other thing about this kind of cancer: It doesn’t respond to some of the medications that work for other types. That means that some of the targeted therapies that work for certain cancer cells, like HER2-positive breast cancer will not be effective. But that doesn’t mean it can’t be treated. Once you’re diagnosed, your doctor will work with you to decide the best treatment plan.

The symptoms of triple-negative breast cancer, once they occur, are often the same as those of other breast cancer types, and include:

  • A lump or mass in the breast
  • Breast pain or redness
  • A nipple that turns inward or has a discharge

Doctors aren't sure what makes you more likely to get triple-negative breast cancer. Not many women do -- it only affects up to 20% of those who have breast cancer. You're most at risk for triple-negative breast cancer if you:

  • Are African-American or Latina
  • Are under 40
  • Have what your doctor will call a BRCA mutation (a change in a gene), especially the gene BRCA1

There's no way to know which type you have until you’re tested by a doctor. When doctors find an area in your breast that isn’t normal, they’ll cut out a little bit of the tissue to test the cells. This is called a biopsy.

A doctor called a pathologist will look at your biopsied tissue under a microscope. The structure will tell him if the cells are normal, precancerous, or cancerous. If it’s cancer, they’ll do more tests to figure out the exact kind. If your cells don’t test positive for estrogen, progesterone, or HER2 receptors, then it’s diagnosed as triple-negative breast cancer. It might take a couple of weeks to get biopsy results.

The doctor will also “stage” your cancer. That’s when they figure out how much of it there is and where it’s located in your body.

  • Which medications do you recommend?
  • What stage is my cancer? Has it spread to lymph nodes (glands near the breast) or other areas?
  • Should I have chemotherapy before or after surgery?
  • What type of surgery will I need?
  • Will I need radiation treatments?

Triple-negative breast cancer is usually treated with a combination of surgery, radiation, and chemotherapy.

  • Chemotherapy, a medicine that kills cancer cells, will likely be the first thing your doctor tries. You can get it by a needle into a vein or in a pill. When it’s caught early, this type of cancer may respond better to chemo than others do. Your doctor can use chemo in one of three ways:
    • Neoadjuvant therapy is when you get chemo before surgery to shrink the tumor and make the operation easier. That makes it the preferred approach if you have locally advanced breast cancer but your doctor doesn’t think they can operate yet, or if your cancer makes it unlikely that your breast can be saved.
    • Adjuvant therapy is used after surgery. You might get it if you have a large tumor or if your lymph nodes are involved. You’re more at risk for relapse. Other types of adjuvant therapy, like hormone treatments, won’t work with triple-negative breast cancer.
    • Immunotherapy is used along with chemo in cases where the cancer has spread and surgery is not an option.

Surgery can be one of two types. Many doctors think that because triple-negative breast cancer is aggressive, it’s best to do a mastectomy to remove the entire breast. This tends to happen if:

  • You have several tumors.
  • The cancer is in your skin.
  • You have a tumor in your nipple.
  • You already had cancer in that breast.
  • The tumor is large.
  • There are calcium deposits or other abnormal cells in your breast.

But there hasn’t been a lot of research on the subject. Your doctor may decide it’s OK to do a lumpectomy and remove only the tumor and the tissues around it.

Radiation is often used after surgery to kill any cancer cells still in the area. The goal is to stop the cancer from coming back. It’s more common after a lumpectomy.

Think about a clinical trial. With so much research on new treatments, it’s a good idea to ask your doctor if this might be right for you. Clinical trials help scientists test new drugs to see if they’re safe and if they work. It's often a good way to get a new medicine that isn't available to everyone.

After your treatment is over, your doctor will want to see you often to make sure the cancer doesn't return. For the first 3 years, you'll likely see them every 3 to 6 months. For 2 years after that, you'll probably visit every 6 to 12 months. Once you've been cancer-free for 6 years, you'll probably go back only once a year. Tell the doctor right away if you get any new symptoms or if you have pain or other problems that relate to your breasts.

Treatment may make triple-negative breast cancer go away. It depends on the size of your tumor, how quickly your cancer grows, and whether the cancer has spread to the lymph nodes or other parts of your body. The treatments may cause side effects like nausea, vomiting, pain, fatigue, or mental fuzziness (which is sometimes called “chemo brain”).

It’s hard to say exactly what the odds are because cancer affects everyone differently. Plus, how well you do depends on how early you catch the cancer and how well you responded to treatment.

In general, about 91% of all women with triple-negative breast cancer are still alive 5 years after diagnosis. If the cancer has spread to the lymph nodes near the breast (regional) the 5 year relative survival rate is about 65%. If the cancer has spread to distant places, the 5 year relative survival rate is 12%.

Although triple-negative breast cancer is more likely to return to another part of your body than other forms, the risk that this will happen drops over time. The risk peaks around 3 years of treatment and falls quickly after that.

No one will understand what you’re going through better than someone else who has this type of breast cancer. In addition to information about the disease, organizations like the American Cancer Society ( and the Triple Negative Breast Cancer Foundation ( can connect you with support groups. You can also check online for groups that meet locally, either through a church or community center.

Don’t forget to tell the people around you what’s going on -- and to ask for help when you need it. It’s up to you who you tell and when, but the more you share with family and friends, the better equipped they’ll be to lend a hand when you need it.