Breast Cancer Inside Cabling can predict which women are more likely to survive or return, researchers say. Breast cancer is 11 separate diseases, each of which has a different risk of return.
The hope is that findings in the Nature magazine can identify people who need closer monitoring and convince others with a low risk of repetition.
Cancer Research UK says work is "incredibly encouraging" but not yet ready
Scientists from the University of Cambridge and Stanford University looked with incredible detail in nearly 2,000 women of breast cancer.
They went far beyond the scope of all types of breast cancer as a disease and beyond the way of modern medicine. Currently, doctors classify breast cancer based on whether they respond to hormone estrogen or targeted therapies like Herceptin.
The research team analyzed the genetic mutations in the tumor to create a new way to classify them.
The group's previous work has shown that breast cancer is 11 separate diseases, each with a different cause and needing different treatment. Following women for 20 years, they can now show which types of breast cancer are more likely to return. Professor Carlos Caldas of the BBC: "This really is a propulsion from biology, that's the molecular wiring of your tumor."
"Once and for all we should stop talking about breast cancer as a disease, it's a constellation of 11 This is a very important step towards a more precise type of medicine.
It has shown that triple negative breast cancers – one of the most difficult types of treatment – are not a cancer class, but two.
Prof. Caldas said: "If women have not had a relapse for five years, they are probably cured, but a second subgroup is still at risk of a later relapse."
The study can help women to be informed about their future risk. , but may also change the way they treat their cancer.
There were four subgroups of breast cancer that had been driven by estrogen and had a "significantly increased" risk of relapse.
These women can benefit from a longer course of hormonal therapy like tamoxifen.
The UK estimates that 12,300 women per year have such cancers.
By James Gallagher, Correspondent on Health and Science, BBC News
To be named at the place where you find them: breast, colon, prostate, lungs .
But it has long been known that this is not good enough.
This study shows the future of personalized medicine and the adaptation of treatment to the specific causes of someone's cancer. Studies are already in progress that examine which treatments can work best for different subtypes of breast cancer.
Other research groups are also trying to gain a similar understanding of other forms of cancer.
- New age of personalized cancer drugs
However, the way scientists analyzed and sorted cancer is still too complex to be introduced into the NHS. It is necessary to transform it into a form that can be used as a routine way to analyze a woman's cancer. Extensive studies are planned, involving up to 12,000 women, so researchers can be sure of their results.
Prof. Caldas said, "I would not recommend it yet clinically, but we are really committed to making it available." "We are fully committed to conducting an NHS test, we have not patented anything. "
Prof. Karen Vouson, a Cancer Research UK scientist, said:" We are still far from being able to offer this type of detailed molecular testing to all women and we need more research to find out how we can adapt the treatment to individual tumor biology of the patient. "But this is incredibly encouraging progress."
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