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Cancer is one of the main causes of death in our society, it is a very complex disease and although much progress has been made in its study, usually when it is diagnosed it is usually late.
That is why the early detection of cancer when it has not yet spread to other parts of the body is the dream of all the scientists involved in this disease.
To date, to detect cancer through blood tests, experts have studied the cells of blood samples from patients diagnosed with cancer, looking for certain types of mutations in their DNA.
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Obviously with this method the only thing we can know is if our detection method is as good as the others but we cannot demonstrate that it is better, since all the samples are affected.
To change this, a group of scientists from the University of California San Diego recruited a group of 123,000 people from whom they took an annual blood sample until they obtained more than a million samples.
Of all the participants, 1,000 developed cancer during the test, which allowed a comparative study of the samples with healthy patients, being able to detect the cancer up to 4 years before presenting any symptoms.
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This initial test was designed to detect the 5 most common types of cancer: stomach, esophagus, colorectal, lung, and liver.
As usually happens in these cases, there will still have to be lots of tests and checks before they can be applied in hospitals normally, but all the advances in this regard are very encouraging.
More information:
https://www.scientificamerican.com/article/experimental-blood-test-detects-cancer-up-to-four-years-before-symptoms-appear/
Versión en español