A new test could help doctors plan better treatment for women with aggressive and deadly forms of breast cancer.

A new test has been developed that can show if breast cancer is likely to spread to the brain.

The test, which looks for high activity in a gene called alpha beta crystallin, could help doctors plan better treatment for women with aggressive and deadly forms of the disease.

Researchers, who studied almost 4000 breast cancer patients, found that women with the active gene were three times more likely to have cancer that had spread to the brain.
In a further analysis, alpha beta crystallin was also linked to a greater risk of death.

A quarter of participants who tested negative died within 10 years of their diagnosis, compared with 36 per cent of those who tested positive.

Study co-leader Dr Maggie Cheang, from The Institute of Cancer Research in London, said: "Spread of breast cancer to the brain is unfortunately very dangerous and usually leads to death within months.

"It's important to find new ways to identify women who are most at risk of their cancer spreading to the brain, so that doctors can work out which women might need more intensive or new treatments to try to keep their cancer at bay for longer.

"Our study linked a positive score in this test with quicker spread to the brain and, importantly, showed the factor we were measuring is providing information on patient outcome independently of other biomarkers already measured in the clinic.

"The test needs further development before it will be ready for routine clinical use, but ultimately, the first use of this type of test could be to identify opportunities for women with advanced specific types of breast cancer - such as triple negative - to enter clinical trials of new treatments."

The findings are published in the open-access journal NPJ Breast Cancer.

Co-author Professor Torsten Nielsen, from the British Columbia Cancer Agency in Canada, said: "It has taken us years to assemble the clinical outcome database and tissue samples, generate the immunohistochemical biomarkers (and) gene expression profiles, and analyse the data for this study.

"We were delighted to find a definite link between alpha beta crystallin and breast cancer progression, which we hope will ultimately improve clinical outcomes."