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.

Breast cancer causes

Studies continue to look at how certain lifestyle factors, habits, other environmental factors, and inherited gene changes (mutations) might affect breast cancer risk.

Gene changes

Some breast cancers run in families. Several studies are focusing on the best use of genetic testing for inherited breast cancer gene changes. Other studies are being done to identify inherited gene changes that are not yet known.

Scientists are also exploring how common gene changes known as variants might affect breast cancer risk. These types of gene changes typically have only a modest effect on risk by themselves, but when combined, they could possibly have a large impact.

Other causes

Possible environmental causes of breast cancer have also received more attention in recent years. While much of the research on this topic is still in early stages, this is an area of active research.

Breast cancer prevention

Researchers are looking for ways to help reduce breast cancer risk, especially for people who are at high risk.

Lifestyle factors

Studies are looking at whether certain levels of physical activity, losing weight, or eating certain foods or types of diets might help lower breast cancer risk.

Medicines

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.

Studies are also looking at whether some nonhormonal drugs might lower breast cancer risk.

Risk-reducing surgery

For people at very high risk, such as those with certain inherited gene changes, researchers continue to study the benefits and timing of risk-reducing surgery.

Newer tests to personalize your treatment

Biomarker and liquid biopsy tests are being developed and studied to help those with breast cancer.

Biomarkers

Breast cancer tissue is routinely tested for certain biomarkers such as hormone receptors 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. Studies are looking at whether testing for other biomarkers or even groups of biomarkers might help predict a person’s prognosis (outlook) or decide which treatments might be best.

Liquid biopsies and circulating tumor DNA

Circulating tumor DNA (ctDNA) is DNA that is released into the blood when cells die. Breast cancer cells can also release DNA into the blood. This can be detected and measured using tests on a blood sample, which is sometimes referred to as a liquid biopsy. Testing the ctDNA in the blood for cancer biomarkers is a rapidly growing area of study.

Measuring ctDNA might help determine whether:

• Small amounts of cancer remain in the body after treatment, even if they can’t be seen on imaging tests, which is known as minimal residual disease (MRD). This might help predict the risk of recurrence or whether further treatment is needed.
• A certain drug will work on a tumor before trying it
• The cancer has become resistant to a drug
• Breast cancer has come back after treatment, before it can be seen on an imaging test like a mammogram

Newer 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 whether they are as good as or better than those used today. Some of these tests include:

• Scintimammography (molecular breast imaging)
• Positron emission mammography (PEM)
• Contrast-enhanced mammography (CEM)
• Electrical impedance imaging (EIT)
• Elastography
• Magnetic resonance spectroscopy (MRS)
• 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.

More and better treatment options are needed, especially for cancers like triple-negative breast cancer, where some types of medicines aren’t likely to be helpful.

New types of treatment

Research being done on new types of treatment includes:

• Testing whether different types of radiation therapy, such as proton beam radiation, might be better than standard radiation.
• Combining different types of drugs to see whether they work better together.
• Trying to find new drugs or drug combinations that might help treat breast cancer that has spread to the brain.
• Treating hormone-positive and HER2-negative advanced breast cancer with newer drugs called selective estrogen receptor degraders (SERDs), such as elacestrant and imlunestrant, if the tumor cells have an ESR1 gene change.
• Testing different immunotherapy drugs to treat triple-negative breast cancer.
• Studying and expanding the use of antibody-drug conjugates (ADCs), which deliver chemotherapy directly to cancer cells. These drugs are already used for some types of breast cancer, and researchers are looking at using them earlier in treatment.
• Finding new treatment options when breast cancer becomes resistant to current treatments.

Whether less treatment is better

Since many cancer treatments have side effects, research is being done to weigh the benefits and risks of each treatment. For example, studies are being done to determine:

• Whether some women with ductal carcinoma in situ (DCIS) can be watched closely instead of being treated with surgery.
• Which people with breast cancer need to have the lymph nodes under their arm removed, or even checked, as part of their treatment.
• Whether shorter courses of radiation therapy for very early-stage breast cancers are at least as good as the longer courses now often used.
• Whether some people can safely get less treatment, such as shortening or even avoiding chemotherapy, to reduce side effects.

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 ways to try to improve supportive care for people with breast cancer. For example, researchers are studying:

• Medicines or ways to prevent the damage to nerves that sometimes happens with certain chemotherapy drugs.
• Medicines to help protect fertility before or during chemotherapy.
• Drugs or other treatments to help limit memory problems and other brain symptoms after chemotherapy.
• Whether certain heart or blood pressure drugs can help prevent the heart damage sometimes caused by common breast cancer drugs such as doxorubicin and trastuzumab.
• Medicines to help treat the fatigue that cancer or its treatment can cause.