Triple-negative breast cancer (TNBC) is a rare type of breast cancer. It accounts for 15% of all breast cancer cases. Unlike most breast cancer types, triple-negative breast cancer cells don’t have the receptors or proteins that help cancer grow and spread. Chemotherapy is the most common treatment. Medical researchers are studying new treatments.
Triple-negative breast cancer (TNBC) is a rare form of invasive breast cancer. It accounts for 15% of all invasive breast cancer cases. Unlike most breast cancers, triple-negative breast cancer cells don’t have the following characteristics:
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Triple-negative breast cancer symptoms are the same as other more common breast cancers. TNBC symptoms may include:
As you think about your situation, remember, many breast cancer symptoms are like other less serious conditions. That means having certain symptoms doesn’t necessarily mean you have breast cancer.
Researchers don’t know the exact cause, but they do link it to mutations in the BRCA genes.
Triple-negative breast cancer is more likely to affect:
The first step might be a mammogram to evaluate a suspicious mass or lump in your breast. Based on what they learn, healthcare providers might perform a biopsy to remove breast tissue. Medical pathologists determine subtype by studying cells under a microscope.
Sometimes, providers use the following tests before treatment to determine tumor size and whether it has spread:
It spreads faster than other types of breast cancer. A 2016 study analyzing how much breast cancer tumors grew between the time of diagnosis and surgery found that triple-negative breast cancer tumors grew by 1% each day. In comparison, HER2-positive breast cancer tumors grew 0.859% each day.
Healthcare providers use the TNM cancer staging system to plan treatment. (T stands for tumor size, N stands for cancer in lymph nodes and M stands for metastasis, or if the cancer has spread.) Breast cancer stages are:
Healthcare providers and medical researchers continue to investigate new ways to treat TNBC. Recent clinical trials are testing new combinations of drugs and new approaches to existing treatments. Some existing treatments include:
Each treatment has different side effects. And each person might have different reactions to these side effects. Ask your healthcare provider about specific treatment side effects. They’ll explain what they’ll do to help you manage them, and what you can do to help yourself.
Researchers don’t know what causes triple-negative breast cancer, but they do link this condition to mutations or changes in the BRCA genes. However, there are steps that help prevent breast cancers, including TNBC:
The prognosis for TNBC continues to improve, thanks to recent progress in identifying new treatments like immunotherapy and PARP inhibitors. Medical researchers are finding new ways to use existing treatments. Like most cancers, the earlier healthcare providers diagnose triple-negative breast cancer, the better the prognosis.
Not right now, but there are treatments to help people to live longer with the condition, including cancer that comes back after treatment or has spread. For example, the U.S. Food and Drug Administration (FDA) recently approved a new type of treatment for metastatic TNBC. Antibody-drug conjugates help cancer treatments home in on tumors by targeting cancer-specific antibodies.
According to the American Cancer Society, survival rates vary depending on cancer stage at diagnosis:
It’s important to remember survival rates are estimates based on other people’s experiences and often don’t reflect current data or the impact of newer treatments. Ask your healthcare provider what you can expect. They’re your best resource for information.
Taking care of yourself is one of the most important things you can do to help yourself. Many times, cancer makes people feel as if they’ve lost control of their lives. Committing to self-care is one way to overcome that feeling. Here are some things you can do during and after your treatment:
It’s important that you have regular follow-up care with your healthcare providers. They’ll probably want to do physical examinations every three to six months for the first three years after treatment. They might reduce your visits to every six months in the fourth and fifth years after treatment.
You might also have unusually strong side effects from your cancer treatment. While your healthcare provider likely gave you medication to help control your side effects, you should go to the emergency room if your side effects continue despite medication.
Many cancer treatments affect your immune system, increasing the chance you’ll develop infections. Symptoms that might require an emergency room visit during treatment are:
You’ll probably have many questions about your diagnosis. Here are some basic questions you might ask:
A note from Cleveland Clinic
Triple-negative breast cancer (TNBC) is one of the more challenging breast cancers to treat. You might be discouraged by what you’ve read about the condition. But there are several very effective treatments for TNBC, including immunotherapy, chemotherapy, surgery and radiation. And every day, researchers learn more about this rare cancer. Their knowledge is your power. If you’re concerned you aren’t getting the straight story about your cancer, ask your healthcare provider to walk you through your diagnosis and treatment options.
Last reviewed by a Cleveland Clinic medical professional on 05/15/2023.
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