A new study suggests that diagnosing cancer years before symptoms can happen soon,media BGR reported. A large-scale research project, which began in 2007, has shown promising results, with scientists able to detect stomach, esophagus, colorectal, lung and liver cancers by a blood test four years before symptoms appear. Early detection of cancer will give patients and doctors more time to treat malignant tumors, prevent cancer cells from spreading in the body, and reduce mortality.
If accurate, this test can help diagnose some of the most common types of cancer and prepare patients and their doctors for treatment. The new study, published in the journal Nature-Communications, explained that their methods can use a single blood sample to diagnose stomach, esophageal, colorectal, lung and liver cancers. Results can be obtained within four years of the patient’s onset of symptoms.
“What we’re showing is that for four years before these people walk into the hospital, they have a signature in their blood that says they have cancer,” Zhang Kun, a bioengineer at the University of California, told Scientific American. “It’s never been done before.”
Unlike past efforts, including testing blood samples of people who have been diagnosed with cancer, Zhang and his team have taken a new approach. Instead of looking in the blood for DNA that can detect malignant growth in the body, the researchers began collecting samples of people before they developed any symptoms.
The project began in 2007, when researchers recruited more than 123,000 volunteers from Taizhou, China. They undergo annual health checks, which include blood samples. A special warehouse was set up to store more than 1.6 million specimens. About 1,100 participants developed cancer over the next 10 years, and the researchers then tested some of the samples collected to look for cancer signals.
The researchers created a test called PanSeer that can detect methylation patterns, which may be linked to various types of cancer. This is a chemical process involving a compound that interacts with DNA to alter genetic activity. The test measured DNS methylation at 500 locations in the blood sample, which had previously been identified as possible signals for cancer. The machine algorithm is then used to determine a score that will indicate a person’s likelihood of cancer.
The researchers tested samples from 191 participants who eventually developed cancer, as well as 191 healthy people. Tests showed that it could predict cancer for up to four years before symptoms appeared. Scientists say the test is 90 percent accurate and 5 percent falsely positive.
While more research is needed to validate the study, it appears to be a big step in the right direction. Such tests could give patients an important warning that they could develop cancer in the next few years and help them screen out all types of cancer covered by the PanSeer test before any symptoms appear. Their attending physician sat in the early stages of the tumor to install treatments to save more lives.
While this sounds promising, the PanSeer test may take some time to be widely used. Even if approved by regulators, the test will not always come as expected, it will not be effective for all types of cancer. “There are some cancers that can make a big difference if they are detected early.” Pancreas cancer is his team’s next study, Zhang said.