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Breast Cancer

What’s New in Breast Cancer Research?

Researchers around the world are working to find better ways to prevent, detect, and treat breast cancer, and to improve the quality of life of patients and survivors.

Research studies

Current guidance on preventing and treating breast cancer as well as what might cause it (among other things) has come mainly from information discovered from research studies. Research studies can range from studies done in the lab to clinical trials done with hundreds of thousands of people. Clinical trials are carefully controlled studies that can gather specific information about certain diseases as well as explore promising new treatments.

Clinical trials are one way to get the latest cancer treatments that are being investigated. Still, they are not right for everyone. If you would like to learn more about clinical trials that might be right for you, start by asking your doctor if your clinic or hospital conducts clinical trials, or see Clinical Trials to learn more.

Breast cancer causes

Studies continue to look at how certain lifestyle factors, habits, and other environmental factors, as well as inherited gene changes, might affect breast cancer risk. Here are a few examples:

  • Several studies are looking at the effects of physical activity, weight gain or loss, and diet on breast cancer risk.
  • Some breast cancers run in families, but many of the gene mutations (changes) that cause these breast cancers are not yet known. Research is being done to identify these gene changes.
  • Several studies are focusing on the best use of genetic testing for inherited breast cancer gene mutations.
  • Scientists are exploring how common gene variants (small changes in genes that are not as significant as mutations) may affect breast cancer risk. Gene variants typically have only a modest effect on risk by themselves, but when combined they could possibly have a large impact.
  • Possible environmental causes of breast cancer have also received more attention in recent years. While much of the science on this topic is still in its earliest stages, this is an area of active research.

Breast cancer prevention

Researchers are looking for ways to help reduce breast cancer risk, especially for women who are at high risk. Here are some examples:

  • Studies continue to look at whether certain levels of physical activity, losing weight, or eating certain foods, groups of foods, or types of diets might help lower breast cancer risk.
  • Some hormonal medicines such as tamoxifen, raloxifene, exemestane, and anastrozole have already been shown to help lower breast cancer risk for certain women at higher risk. Researchers continue to study which groups of women might benefit most from these drugs.
  • Clinical trials are also looking at whether some non-hormonal drugs might lower breast cancer risk, such as drugs used to treat blood or bone marrow disorders, like ruxolitinib.
  • Studies are looking at vaccines that might help prevent certain types of breast cancer in people who are at high risk for breast cancer (due to presence of hereditary gene mutations or breast cancer in the family).

New tests to personalize your treatment


Breast cancer tissue is routinely tested for the biomarkers ER, PR, and HER2 to help make treatment decisions. A biomarker is any gene, protein, or other substance that can be measured in blood, tissues, or other body fluids. Some studies are looking at whether testing for other biomarkers, such as HER3, might also be helpful, but research on this is still in early phases.

Circulating tumor DNA (ctDNA) is DNA that is released into the bloodstream when cancer cells die. Identifying and testing the ctDNA in the blood for biomarkers is a rapidly growing area of study.

Some ways ctDNA might potentially be used in breast cancer include:

  • Looking for new biomarkers in the tumor cells that might mean the cancer has become resistant to specific treatments (like chemo or targeted drug therapy)
  • Determining if a certain drug will work on a tumor before trying it
  • Predicting if the breast cancer will recur (come back) in women with early-stage breast cancer
  • Predicting if neoadjuvant treatment is working  to destroy the tumor instead of using imaging tests like a CT scan or US
  • Determining if breast cancer or a high-risk breast condition is present before changes are found on an imaging test like a mammogram

New imaging tests

Newer types of tests are being developed for breast imaging. Some of these are already being used in certain situations, while others are still being studied. It will take time to see if they are as good as or better than those used today. Some of these tests include:

  • Scintimammography (molecular breast imaging)
  • Positron emission mammography (PEM)
  • Electrical impedance imaging (EIT)
  • Elastography
  • New types of optical imaging tests

For more on these tests, see Newer and Experimental Breast Imaging Tests

Breast cancer treatment

New kinds of treatments for breast cancer are always being studied. For example, in recent years, several new targeted drugs have been approved to treat breast cancer.

But more and better treatment options are needed, especially for cancers like triple-negative breast cancer, where chemotherapy is the main option.

Some areas of research involving breast cancer treatment include:

  • Studying if shorter courses of radiation therapy for very early-stage breast cancers are at least as good as the longer courses now often used
  • Testing if different types of radiation therapy, such as proton beam radiation, might be better than standard radiation.
  • Combining certain drugs (like 2 targeted drugs, a targeted drug with an immunotherapy drug, or a hormone drug with a targeted drug) to see if they work better together
  • Trying to find new drugs or drug combinations that might help treat breast cancer that has spread to the brain
  • Testing different immunotherapy drugs to treat triple-negative breast cancer
  • Giving cancer vaccines to see if this helps keep the cancer from either worsening or coming back after treatment. There are many ways in which cancer vaccines work. For example, protein vaccines stimulate the immune system to recognize and attack specific cancer proteins.  DNA vaccines contain DNA instructions so that once the vaccine is given, the DNA will instruct your body to make protein(s) to help the immune system recognize and attack cancer cells. 
  • Finding new ways to treat women with hereditary breast cancer, since they have a higher chance of the cancer recurring (coming back)
  • Determining if chemotherapy is needed to treat every woman with HER2-positive breast cancer
  • Finding new treatment options when breast cancer becomes resistant to current treatments

Supportive care

Supportive care helps patients and caregivers manage the symptoms of cancer and side effects of cancer treatment. Clinical trials are looking at different medicines and techniques to try to improve supportive care for people with breast cancer. For example, some studies are investigating:

  • If there are better medicines or ways to prevent the damage to nerves that sometimes happen with certain chemotherapy drugs
  • If drugs or other treatments might be helpful in limiting memory problems and other brain symptoms after chemotherapy
  • If certain heart or blood pressure drugs, can help prevent the heart damage sometimes caused by common breast cancer drugs such as doxorubicin and trastuzumab
  • If there are medicines that might be able to help treat the tired feeling that cancer can cause

The American Cancer Society medical and editorial content team

Our team is made up of doctors and oncology certified nurses with deep knowledge of cancer care as well as editors and translators with extensive experience in medical writing.

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Last Revised: February 15, 2024

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