Decorative image

Causes and prevention research for breast cancer

Researchers around the world are looking at better ways to understand the causes and how to prevent breast cancer.

Go to Cancer Research UK’s clinical trials database if you are looking for a trial for breast cancer in the UK. You need to talk to your specialist if there are any trials that you think you might be able to take part in.

Some of the trials on this page have now stopped recruiting people. It takes time before the results are available. This is because the trial team follow the patients for a period of time and collect and analyse the results. We have included this ongoing research to give examples of the type of research being carried out in breast cancer.

Click on the ‘recruiting’, ‘closed’ and ‘results’ tabs to make sure you see all the trials.


There are already some known inherited gene changes (mutations) that increase the risk of breast cancer. Researchers continue to look into these gene mutations and how they affect breast cancer risk.

Researchers are also looking at other breast cancer gene research. This includes:

  • finding new gene mutations
  • finding other factors that may change the effects of these genes such as lifestyle or environmental to increase the risk of developing breast cancer
  • looking at people with a rare type of breast tumour called Phyllodes tumour. They want to try and find out which genes are involved in their development and to try to understand why some come back
  • creating a register of families who have a fault in the genes BRCA1 and BRCA2, as well as other gene faults. The aim of this is to help doctors in the future to help decide the best way to treat someone who has these faulty genes
  • looking at changes to the genes in tissue from male breast cancer. They want to understand what increases the risk of developing male breast cancer and how it is different from female breast cancer

Diet, smoking, body weight and physical activity

There are many studies around the world looking at ways to reduce breast cancer risk through diet, physical activity and lifestyles choices.

Researchers are looking into giving a 12 week lifestyle programme to those at increased risk of breast or bowel cancer. The advice would be given at the early detection and genetic clinics. The programme involves information about diet, physical activity, body weight, and smoking.

Some researchers are looking a different weight loss programmes for women that have an increased risk of developing breast cancer. They want to see which programme works best to help women lose weight.

Stem cells

Stem cells are undeveloped (immature) cells that can become any type of cell in the body.

Researchers are studying breast stem cells from people without cancer, and from people with different stages of breast cancer. They want to understand more about how stem cells are involved in the start of certain breast diseases. Knowing more about how breast stem cells work may also help to develop future treatments.

Drugs to lower the risk of breast cancer

The National Institute for Health and Clinical Excellence (NICE) provides guidance for women at higher risk of breast cancer. As a result of earlier research, they recommend that women at high or moderate risk of breast cancer should talk to their doctor about taking tamoxifen or raloxifene for 5 years, alongside their other options. Tamoxifen and raloxifene are types of hormone therapy.

Research is continuing to look at how drugs can prevent breast cancer in women with an increased risk of the disease. One trial is looking at a combination of tamoxifen with other hormone drugs, anastrozole and goserelin. 

Due to the side effects of tamoxifen or raloxifene, doctors do not recommend these drugs if you have had a blood clot or are at risk of developing one.

So researchers are looking for other drugs to prevent breast cancer which do not have these side effects. A trial is looking at a drug called Ulipristal acetatete (UA) to see if it helps prevent breast cancer. This drug doesn’t have the same side effects as tamoxifen or raloxifene.

The Breakthrough Generations Study

This is a large study looking into the causes of breast cancer. It is recruiting thousands of women. They are looking into the lifestyle, environmental, genetic and hormonal factors that might affect an individual’s risk of developing breast cancer.