“EXHAUSTED” immune cells could hold the key to stopping breast cancer before it develops, a study suggests.
Existing drugs could be used to prevent women most at risk of the disease from ever suffering it — without the need for surgery, University of Cambridge said.
They found immune cells in the breast tissue of healthy women carrying faulty BRCA1 or BRCA2 genes showed signs of a malfunction known as exhaustion.
This mechanism — usually found in late-stage tumours — suggests the immune cells cannot clear out damaged cells, which eventually leads to cancer.
Professor Walid Khaled said: “Our results suggest that in carriers of BRCA mutations, the immune system is failing to kill off damaged breast cells.
“These in turn seem to be working to keep these immune cells at bay.
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“We’re very excited about this discovery, because it opens up potential for a preventative treatment other than surgery for carriers of BRCA breast cancer gene mutations.
“Drugs already exist that can overcome this block in immune cell function, but so far, they’ve only been approved for late-stage disease.
“Noone has really considered using them in a preventative way before.”
Around 55,000 women and 400 men are diagnosed with breast cancer every year.
A BRCA mutation — made famous by Angelina Jolie — is a mutation in either of the BRCA1 and BRCA2 genes, which are tumour suppressor genes.
The faulty genes affect around one in every 400 people and are particularly prevalent in people of Jewish descent.
Up to 85 per cent of women with either BRCA mutations will develop breast cancer during their lifetimes, according to the NHS.
Some patients with the gene choose to have breast removal surgery to reduce their risk of getting the disease.
The latest study, published in Nature Genetics, offers hope that they may be able to take existing immunotherapy drugs to prevent it instead.
Researchers looked at data from the largest collection of breast cells in the world, containing more than 800,000 cells from 55 women.
They found those from women with a BRCA mutation were more likely to have “exhausted” immune cells, even if they did not already have cancer.
The team are now testing existing immunotherapy drugs — which train the body’s immune system to fight cancer — on mice to see if they could be used to prevent cancer developing.
Dr Simon Vincent, of Breast Cancer Now, said: “The best weapon we could have against breast cancer is the ability to stop it occurring in the first place.
“This research, which used tissue samples from Breast Cancer Now’s Tissue Bank, suggests that we could prevent some women with altered genes from developing the disease by using drugs currently approved for treatment in the late stages of breast cancer.
“While further research is needed and clinical trials in humans are yet to take place, these findings could be a significant step forward in our care and treatment of people whose genes mean they have an increased risk of developing breast cancer.”
How to check your breasts
It is important to regularly check your breasts for any changes. Breast tissue reaches all the way up to your collarbone and across to your armpit, so it’s vital to check these areas too.
If you feel or see any changes in your breast you should always consult your GP.
Charity CoppaFeel! recommends checking your breasts monthly, so you can pick up on any changes quickly.
Breasts do change naturally as part of your monthly menstrual cycle, so you should get to know your breasts, how they feel and what changes they usually go through to know if anything is out of the ordinary.
Five-step check
There is a five-step self exam you can do at home to check for any changes.
Step one: Begin by looking in a mirror, facing it with your arms on your hips and your shoulders straight. You should be looking for any dimpling, puckering, bulging skin, redness, soreness, a rash or changes in the nipple.
Step two: Still looking in the mirror, raise both arms above your head and check for the same changes.
Step three: With your arms still above your head, check for any fluid coming from the nipples. This can include milky, yellow or watery fluid, or blood.
Step four: While lying down use your opposite hand to check each breast. Using a few fingers, keeping them flat and together, go in a small circular motion around your breasts. Make sure you feel the entire breast by going top to bottom in these small circles. It helps to develop a system or pattern to make sure every inch is covered. Use light pressure for the skin and tissue just beneath, medium pressure for the tissue in the middle of your breasts, and firm pressure to feel the tissue at the back, feeling down to your ribcage.
Step five: Feel your breasts while either standing or sitting, using the same small circular motions.