Health
BRCA and beyond: finding younger women with a higher risk of breast cancer – Cancer Research UK
What if all it took to understand your risk of one of the most common types of cancer was a computer program, a saliva sample and a questionnaire from your GP?
That’s the promise of CanRisk. It’s an online platform our researchers built to turn a risk-calculating algorithm called BOADICEA into a powerful, easy-to-use tool doctors can use to identify people with a high risk of breast and ovarian cancer.
Currently, CanRisk is only recommended for genetics specialists, but research is beginning to uncover its wider potential. In August, an early study suggested that offering it to all women under 50 could help spot multiple times more women at increased risk of breast cancer than the guidelines doctors use today.
Those early signs suggest that CanRisk could help change how doctors diagnose, treat and even prevent breast cancer in younger women. For now, though, that’s all hypothetical. First, the team behind CanRisk need to work out how to adapt their specialist tool for everyday care.
The risks we can’t see
Overall, breast cancer is much more common in people over 50. That’s why all women aged 50 to 70 in the UK are invited for breast screening every three years. But age is far from the only risk factor, and the number of women under 50 being diagnosed with early-onset breast cancer is rising.
One of the strongest indicators of increased breast cancer risk at younger ages is family history. So, UK guidelines also recommend that doctors refer younger women for regular screening if there’s a concerning pattern of cancer in their relatives, which may be linked to specific inherited gene changes.
Earlier breast cancer screening based on family history saves lives. But almost 3 in 4 women under 50 who are diagnosed with breast cancer don’t have a family history that might raise alarms. Under the current guidelines, their risk will probably only become clear after they develop breast cancer. Doctors don’t have the same opportunity to monitor them for early signs of the disease or take steps that could prevent it.
The CanRisk programme is an opportunity to change that.
Back to BRCA
Like many stories about preventing cancer, this one goes back to the 1990s. That’s when Cancer Research UK scientists helped discover two tiny segments of DNA that changed the world’s understanding of cancer risk: BRCA1 and BRCA2.
We all have these genes in our cells, where they help repair DNA damage before it becomes dangerous. A very small number of people are born with changes in BRCA1 or BRCA2 that stop them from working, raising the risk of certain cancers, including, as the name makes clear, BReast CAncer.
Thanks to the discovery of BRCA genes, doctors can provide women with changes to them extra care, including earlier and more regular breast cancer screening. Today, Cancer Research UK-funded researchers are also working on new preventative drugs (including vaccines) to help lower the risk of BRCA-linked cancers without the need for surgery.
But BRCA’s impact actually goes further. Once scientists knew how much a single gene change could influence cancer risk, they could begin searching genetic data to find others. BRCA1 and BRCA2 have become lighthouses for researchers to navigate cancer risk by.
The rise of BOADICEA
Professor Antonis Antoniou and his team at the University of Cambridge are some of cancer risk’s most intrepid explorers. They launched BOADICEA as a web tool in 2008, initially to help identify which women with a family history of cancer were most likely to need BRCA testing.
Over time, as the Cambridge team and their international collaborators improved and updated the tool, they also helped uncover the role of many other genetic changes.
“We’ve identified many more kinds of genes involved in cancer risk,” says Antoniou. “Some are rare changes like those to BRCA1 and BRCA2 that can cause a moderate or high risk on their own, but there are also more common variants that can have a joint effect if someone has lots of them.”