A new study suggests that monitoring for circulating cell-free tumor DNA biomarkers can help in detecting cancer in individuals early.
Study led by Hong Kong-based researchers used DNA fragments in the blood to detect a kind of head and neck cancer called nasopharyngeal carcinoma.
The nasopharynx is the upper part of the throat that lies behind the nose, just above the soft part of the roof of the mouth and just behind the nasal passages. It serves as a passageway for air between the nose and the throat.
Individuals who are at high risk for nasopharyngeal carcinoma may benefit from screening using circulating cell–free Epstein-Barr virus (EBV) DNA.
The procedure, known as a “liquid biopsy,” caught nasopharyngeal carcinoma earlier and more accurately than existing methods and ultimately boosted patients’ chances of survival.
The team, led by Y.M. Dennis Lo, FRS, from Chinese University of Hong Kong, China, showed that such screening detected cancer at an earlier stage, leading to superior outcomes.
Nasopharyngeal cancer is closely related to the EBV, a member of the herpes family, Lo explained.
“The EBV genome can be found in more than 99 percent of tumor cells of nasopharyngeal cancer,” Lo said. “It is believed that the virus is one of the causative factors for this cancer.”
Based on this, Lo and his team developed a test to detect fragments of EBV contained in tumor DNA that’s released into the bloodstream as cancer cells die in a patient’s body.
Test screening of more than 20,000 people detected EBV fragments in more than 1,100 people, or about 5.5 percent. Of those, 309 had persistent positive results when tested repeatedly, the researchers found.
The test, which looks for DNA evidence of EBV in blood samples, was 97 percent accurate at detecting the presence of nasopharyngeal carcinoma.
The study was published in the New England Journal of Medicine.