Earlier this year, I told you about a new blood test—called Galleri—that could detect up to 50 different types of cancer.
It’s currently under development by the healthcare company Grail, and uses cutting-edge sequencing technology to examine methyl groups on circulating DNA in blood samples.
And although it isn’t approved yet by the U.S. Food and Drug Administration (FDA), it is commercially available for about $950.
Of course, the U.K.’s National Health Service has been using the Galleri blood test in a pilot trial. And promising, new results are in…
Accurate and specific
First and foremost, the test successfully detected signals for more than 50 types of cancer. And its overall accuracy (its ability to predict the origin of cancer in truly positive cases) was incredibly impressive, at 88.7 percent.
Plus, specificity for cancer signal detection was 99.5 percent—which means that fewer than one percent of the results were false positives. (“Specificity” refers to the test’s ability to accurately identify patients without the disease—in other words, it’s true negative rate.)
Its overall sensitivity, however, was only 51.5 percent. (A test’s “sensitivity” refers to its ability to accurately identify patients with the disease, or its true positive rate.) But the good news is, this percentage rose with higher-grade cancers:
- For stage 4 cancers, sensitivity rate was 77 percent.
- For stage 2 cancers, sensitivity rate was more than 40 percent.
- For stage 1 cancers, sensitivity rate was nearly 17 percent.
It was also higher among the dozen cancers that account for the majority of deaths in the U.S. every year: anal, bladder, bowel, esophageal, stomach, head and neck, liver and bile duct, lung, ovarian, and pancreatic cancers—as well as lymphoma and multiple myeloma.
For these cancers, sensitivity rate was 76.3 percent across all stages—and more than 67 percent for the first three stages.
Finally, statistical manipulation showed a negative predictive value of an astounding 99.4 percent—which basically means that, if the test is negative, it’s highly unlikely that you have cancer.
Not ready for prime time yet
It’s hard not to get excited about these latest findings—especially given how closely they reflect previous findings. But obviously, this blood test isn’t quite ready for prime time just yet—and it definitely isn’t able to replace conventional cancer screens.
Until the test gets a little further refined (and its overall sensitivity rate increases), its main benefit would probably be for high-risk patients—either due to age (anyone over 50) or other risk factors. (For example, researchers want to see how well it can work in patients with genetic predispositions to cancer, like BRCA or Lynch Syndrome.)
The Galleri blood test could also be used the same way that I use tumor markers (which aren’t too reliable by themselves): that is, to detect any disease that might be left behind after treatment, to monitor response and recurrence (measures that we desperately need).
In any case, I’m hopeful that this technology may eventually mean the end to all of the invasive testing we do now. Because having such a simple, comprehensive, and non-invasive test like this is a HUGE deal.
Of course, even then, some things will never change—like the fact that taking care of your body will always be the best insurance against cancer you can get.
So, if you’re looking for simple, science-based strategies to help prevent or fight this disease, I highly encourage you to check out my Essential Cancer Protocol. To learn more about this innovative online learning tool, or to enroll today, click here now.
“Blood Test for Many Cancer Types as Supplement to Screening.” Medscape Medical News, 06/25/2021. (medscape.com/viewarticle/953733)