In recent times it seems something fascinating has happened. A recent study has shown that a specific blood test can detect five types of cancer before they’re spotting traditionally.
When it comes to cancer early detection is important. The sooner you find out something is going on within your body the sooner you can begin to treat it and from there get rid of it before something terrible happens. Cancer is a very serious thing in the world right now and has been for a long time. It has claimed far too many lives.
The abstract for this specific study goes as follows and is titled ‘Non-invasive early detection of cancer four years before conventional diagnosis using a blood test’:
Early detection has the potential to reduce cancer mortality, but an effective screening test must demonstrate asymptomatic cancer detection years before conventional diagnosis in a longitudinal study. In the Taizhou Longitudinal Study (TZL), 123,115 healthy subjects provided plasma samples for long-term storage and were then monitored for cancer occurrence. Here we report the preliminary results of PanSeer, a noninvasive blood test based on circulating tumor DNA methylation, on TZL plasma samples from 605 asymptomatic individuals, 191 of whom were later diagnosed with stomach, esophageal, colorectal, lung or liver cancer within four years of blood draw. We also assay plasma samples from an additional 223 cancer patients, plus 200 primary tumor and normal tissues. We show that PanSeer detects five common types of cancer in 88% (95% CI: 80–93%) of post-diagnosis patients with a specificity of 96% (95% CI: 93–98%), We also demonstrate that PanSeer detects cancer in 95% (95% CI: 89–98%) of asymptomatic individuals who were later diagnosed, though future longitudinal studies are required to confirm this result. These results demonstrate that cancer can be non-invasively detected up to four years before current standard of care.
This test is called PanSeer and it works because it detects methylation patterns. This can seemingly detect things like stomach cancer, esophageal cancer, lung cancer, liver cancer, and colorectal cancer which is mind-blowing. Things like this are extremely important moving forward and could truly change the world as a whole as these are some more common types of cancer as well.
Scientific American wrote as follows on this blood test and how it works:
The PanSeer test works by isolating DNA from a blood sample and measuring DNA methylation at 500 locations previously identified as having the greatest chance of signaling the presence of cancer. A machine-learning algorithm compiles the findings into a single score that indicates a person’s likelihood of having the disease. The researchers tested blood samples from 191 participants who eventually developed cancer, paired with the same number of matching healthy individuals. They were able to detect cancer up to four years before symptoms appeared with roughly 90 percent accuracy and a 5 percent false-positive rate.
The new study “offers several interesting approaches in the quest for a blood-plasma-based cancer-screening test,” says Colin Pritchard, a molecular pathologist at the University of Washington School of Medicine, who was not involved in the research. It will be important, though, for another research team to independently validate the findings in a different group of people before the test can be considered for clinical use, he says.
Usha Menon, a professor of gynecological cancer at University College London, who also did not participate in the study, observes that Zhang and his colleagues’ method provides a robust, preliminary baseline test—an “essential first step” toward a commercial cancer-screening product. “The authors are not suggesting that they have a test that can be used clinically at this stage,” she says. “They are clear that what they have is a robust preliminary demonstration of early detection of multiple cancer types four years prior to conventional diagnosis.”
Most likely, such a test would first target high-risk populations, Menon says. And it would require devising a second panel of tests to enable clinicians to determine the specific cancer type and rule out false positives.
Zhang believes such a feature could be developed with more work, and he agrees that further studies are needed. Given the challenges in repeating an effort of this magnitude, a government-industry partnership, he says, would ideally undertake the follow-up research. An ideal test would target the most common cancers, as Zhang’s study did, as well as the deadliest ones. “There are cancers where early detection can make a really big difference,” he says. Pancreatic cancer, for example, is the next target Zhang and his colleagues are working on.
As noted above more research does need to be done but this is a huge step towards something very powerful. While we do not yet know where it will take us we are hopeful these researchers are able to really harness the full potential of something like this. I for one am quite excited to see how this is put to use in the future.