Liquid Biopsy Testing

One in ten men who tested positive had cancer without knowing it. 

The quest for a simple blood test to catch cancer early has attracted big players from Bill Gates to Merck & Co. Now, scientists have the first major evidence that liquid biopsies hold promise for screening people for cancer, at least in certain circumstances. 

A study led by Hong Kong researchers and published this week in the New England Journal of Medicine, was led by Dennis Lo, who is known for discovering that fetal DNA can be found in a mothers blood, which launched a new era of non-invasive testing for pregnant women.

A Good Test Case for DNA Screening

The study involved nasopharyngeal cancer, which is a very common form of cancer in middle-aged men in South China. This type of cancer is aggressive, and forms at the top of the throat and behind the nose, where early detection matters a lot. About 20,000 men were tested, and 300 patients who tested positive twice were given in depth examinations such as magnetic resonance imaging, or MRI, which led to 34 cancer diagnoses.  

This shows that one in ten men who tested positive actually had cancer unknowingly. 


 Read more about the big challenges of working with ctDNA


The data presented “suggest that lives have been saved because of this screening,” Richard Ambinder, a professor of oncology at Johns Hopkins School of Medicine who wasn’t involved in the study, wrote in an accompanying editorial in the journal.

The results could help the commercial prospects for Grail Inc., a Silicon Valley startup that has raised more than $1.1 billion since its 2016 launch, from investors including Bill Gates, Merck & Co, Jeff Bezos and Arch Venture Partners. At the time of launch, Baselga said: “If this pans out, this could be a real game changer.”  Not more than a week ago, GRAIL announced leadership changes to support the company’s next phase of growth as it moves towards commercialisation of early detection products.

Earlier this year, GRAIL merged with Cirina, a small startup founded by leader of the study, Dennis Lo, which is drawing it closer to commercialization by bringing in a number of important patents. 

Lo said in a statement that his blood test isn’t commercially available in Hong Kong as of yet, while Grail has declined to reveal its commercial timeline. 

“It’s our aspiration to create a commercial test” for nasopharyngeal carcinoma, Grail’s president, Ken Drazan told the Washinton Post. If successful, the test, to be marketed in Southeast Asia, would be Grail’s first product.

Preventative Health Care Causing Eager Investors

It’s been predicted that non-invasive tests could revolutionise cancer care, with the rise of technologies like genetic sequencing. Detecting disease early is something that could make treatment more effective, making investors eager to fund ventures focused on such preventative health care. 

Lo and his team seem to have proven that liquid biopsy testing works, however, nasopharyngeal cancer is a special case. 

The researchers estimate that, overall, it cost a total of $28,600 to identify each cancer case. “It may be worth it in Hong Kong, but maybe not in places like the U.S. where the disease is rare, and more people would have to be screened at a greater cost to find each case,” said Dr. Richard Ambinder of Johns Hopkins School of Medicine, who wrote a commentary in the journal.

Before bringing any test to market, GRAIL would need to show extremely low rates of both false positives and false negatives, the former could lead to unnecessary treatment, while the latter could give patients a mistaken sense of security, writes the Washington Post.