Researchers have developed a blood test that can detect oral cancer in people at risk, much before clinical diagnosis.

A study, conducted by researchers from National Cancer Institute has found that it is possible to detect antibodies against the human papillomavirus (HPV), which could in turn be used to identify people at a risk of developing HPV-related mouth cancers.

Cancers of the mouth or throat were earlier thought to be largely related to lifestyle factors such as consuming tobacco or alcohol. However, it is observed that the number of people developing oral cancer due to infection with HPV, especially with HPV type 16 (HPV16) have been increasing of late. About 60 percent of all oropharyngeal cancers in the U.S. are linked with HPV16 infection.

Previous studies have shown that people suffering from oral cancers have antibodies against HPV E6 (a viral gene) in their blood.

Samples for the study came from a database of over 500,000 adults in 10 European countries. These people were a part of the European Prospective Investigation into Cancer and Nutrition Study that stores the participants' blood samples and keeps track of their health.

For the study, researchers analyzed blood samples of 135 individuals who had developed oropharyngeal cancer. Results showed that 47 or about one third of the samples had antibodies against HPV 16 E6 in their blood, around 1 to 12 years before the disease developed.

Researchers found that the presence of these antibodies was independent of the time of diagnosis. They even found the presence of these antibodies in blood samples that were taken a decade before the cancer detection.  

"Our study shows not only that the E6 antibodies are present prior to diagnosis-but that in many cases, the antibodies are there more than a decade before the cancer was clinically detectable, an important feature of a successful screening biomarker," said Aimee R. Kreimer, Ph.D., the lead Investigator from the Division of Cancer Epidemiology and Genetics, NCI, according to a news release.

Researchers add that that the study findings are preliminary and that more research would be required to affirm if detection of HPV16 E6 antibodies could be used as a screening method.

The study is published in the Journal of Clinical Oncology.