Millions of people are screened for cancer each year, but 70% of cancers don’t have screening tests.

The Grail Galleri Test is one of the first blood test that looks for fragments of DNA circulating in the bloodstream, and scans for markers that might have come from a tumor cell.

“It's a novel technology that enables one to potentially screen an individual's blood for up to 50 different types of cancer,” Elizabeth O'Donnell with the Dana-Farber Cancer Institute said. “It uses your blood to look for signatures that may be indicative of a cancer." 

By using two test tubes of a patient's blood, O'Donnell can see if cancer signals are present. A positive test means a signal that is associated with cancer has been found, but it does not mean you have cancer. 

Those who test positive will be further evaluated.

“The intent of all of these liquid biopsies is really to try and find these earlier stages, so stage one and stage two cancers,” O’Donnell said.

The multi-cancer early detection, or MCED, test made by Grail is the first MCED test to be laboratory approved. The test is intended for people who are over the age of 50, and it is not recommended for people under age 21. The test is not yet approved by the FDA, and is not yet covered by health insurance. It’s available by prescription only and costs about a thousand dollars.

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