A genetic test that accurately predicts the risk of developing breast cancer could soon be used on high-risk groups.
Researchers behind the test say it could reduce the number of women choosing pre-emptive mastectomy surgery as they will be able to make more informed decisions about their care.
The blood test looks at 18 genetic variations, or single-nucleotide polymorphisms (SNPs), known to affect the chances of getting breast cancer.
It will initially only be available at St Mary’s hospital and Wythenshawe hospital in Manchester to women having tests for BRCA1 and BRCA2 gene mutations.
A study carried out by researchers at the hospitals and the University of Manchester analysed the DNA of 451 women with a family history of breast cancer who had developed the disease, using the information alongside other factors to predict an overall risk estimate.
Many of the women who were originally in the high-risk category were reclassified to a lower risk category, where risk-reducing breast removal surgery is not recommended.
The study suggested the number of women with BRCA1 and 2 mutations who choose to have a mastectomy could be reduced from 50% to about 36%.
Becky Measures, who had a mastectomy at Wythenshawe hospital 11 years ago after learning she carried the BRCA1 gene mutation, said: “When they find that they have the BRCA1/2 gene, many women fear that they have to take action immediately. The new test will give women more options and help them to make a more informed decision.”
Probably the most famous person to have undergone the surgery is actor Angelina Jolie, who made the decision after learning she had an up to 87% chance of developing breast cancer, a disease her mother had died of.
Following the revelation, referrals for the gene mutation tests more than doubled in the UK, which doctors described as the “Angelina effect”.
While all women with a BRCA gene mutation are given this same risk figure of 87%, it is actually much more complex and different for every person.
A breast cancer charity described the more tailored approach as an exciting development.
Lester Barr, the chairman of Prevent Breast Cancer, which partly funded the research, said: “With more accurate genetic testing, we can better predict a woman’s risk of developing the disease and therefore offer the appropriate advice and support, rather than a ‘one size fits all’ approach.
“It’s so exciting to see this additional test go into clinical practice, as it’s this more tailored method that will help us on our mission to protect future generations from breast cancer.”
The research was led by Prof Gareth Evans, a medical genetics expert at the University of Manchester and Saint Mary’s hospital.
“This new test will help women at risk of familial breast cancer to make more informed decisions about their care,” Evans said. “BRCA1 and BRCA2 are just part of what we should be looking for when assessing risk and in Manchester we plan to incorporate screening for these new genetic markers in clinical practice within the next six months.” – Guardian News and Media
