All types of cancers and their location can be detected by blood test, thanks to a new study. The research found that 50 types of cancer could be detected with accuracy using the new blood test.
The test is done on the DNA that is shed by the tumours and circulating in the blood. The test focuses on the chemical changes happening in the DNA (methylation pattern). An international team of researchers led by Dana-Farber Cancer Institute and the Mayo Clinic conducted the study.
The Annals of Oncology published the study. The test was designed using a machine learning algorithm (a kind of artificial intelligence). Methyl groups help to control if the genes are active or inactive. In cancer cells, methylation pattern is often different from normal cells. Abnormal methylation patterns are more characteristic of cancer cells than genetic mutations. Once tumor cells die, their DNA empties into the blood and the tests can be performed with much accuracy, the study said.
The researchers analysed DNA from normal and cancerous cells that had entered into the bloodstream in 6,689 blood samples. This included 2482 blood samples from people diagnosed with cancer and 4,207 from those without cancer. The study showed that 99.3 per cent was accurate. Only 0.7 results were shown as incorrect.
The researchers could detect about 50 types of cancers and their patterns. However, they said that the results could be better if the disease was more advanced. It said that cancer was detected correctly in 18 per cent of those with stage I cancer. This was 93 per cent accurate in stage IV cancer.
