Researchers in Denmark have come up with a simple blood test that can predict breast cancer up to five years before it develops. And even better - it's got an accuracy level of 80 percent, making it more effective than our current mammography tests, which are 75 percent accurate, and only after a person has already developed the cancer.

The University of Copenhagen team wanted to come up with a better option for breast cancer screening that was not only more accurate, but solved the problem of false positives that has been plaguing mammography for years. Last year, a study involving 13,000 women found that screening via mammography misses more than 2,000 cases of breast cancer per year in the UK alone, while falsely alerting other women that they have the disease when they don't.

Part of the problem with mammograms is dealing with those who have dense breast tissue - about one in three women do. Not only does it significantly increase your risk of developing breast cancer, but dense breast tissue makes it harder for the mammogram to pick up on any tell-tale lumps. Researchers have urged that ultrasounds be used part of the breast screening process in conjuction with mammograms - particularly for more at-risk women - to achieve better accuracy.

But perhaps this new blood test can change all that. It works by "measuring all of the compounds in the blood to build a 'metabolic profile' of an individual, in order to detect changes in the way chemicals are processed, during a pre-cancerous stage," says Laura Donnelly at the Telegraph. The concept is the same one used by researchers from Harvard University in the US to predict a person's liklihood of developing cancers such as leukaemia, lymphoma, and myelodysplastic syndrome in years to come, by looking for certain tell-tale mutations believed to originate in their blood stem cells.

To test the new breast cancer blood test's efficacy, the Danish researchers observed 57,000 participants over 20 years, gathering blood samples along the way. A smaller selection of 800 women was split into two groups - those who remained healthy throughout the entire process, and those who developed breast cancer within seven years of their first blood sample - and their blood samples were compared and their metabolic profiles built. The method was also used to to predict breast cancer in a different dataset of women who were examined in 1997.

The researchers found they were able to predict, with 80 percent accuracy, which patients would be affected by the disease, just by looking at the metabolic profiles they built from the participants' blood samples. And while 100 percent accuracy is always better, the big benefit of this test is that it gives at-risk women a head-start in fighting the disease. Early detection is crucial for breast cancer - if you catch it up to stage 2, you have a 93 to 100 percent chance of surviving the diseases, which drops down to 72 percent at stage 3, and 22 percent at stage four. And by building a metabolic profile for each patient who undergoes the test, the potential is there to predict a whole host of other diseases too.

"It is not perfect, but it is truly amazing that we can predict breast cancer years into the future," lead researcher Rasmus Bro told The Telegraph.

The results have been published in Metabolomics.

"These exciting findings could help us move a step closer to being able to identify a woman's individual risk of developing breast cancer," Samia al Qadhi - Chief Executive at Breast Cancer Care in the UK, who was not involved in the research - told Donnelly at The Telegraph. "The earlier breast cancer is diagnosed the more effective treatment may be. So we welcome any new research, like this, that may offer the possibility of knowing which women may develop the disease in the future."

Fingers crossed they can get this through clinical trials and out to the public.

Source: The Telegraph