U.S researches reported on Monday that lung cancer can be detected as early as a year before the symptoms emerge, by analyzing the blood for particular proteins.  

According to the research conducted on the blood samples taken from the smokers, it was found that  three proteins or antigens were present in more than half of the people who later developed lung cancer.  

Dr. Samir Hanash of the Fred Hutchinson Cancer Research Center in Seattle said “The fact that we got a signal like this with just three biomarkers is very significant.”

Hanash further said "If we can enlarge this panel by adding a few more, we could develop a blood test with sufficient sensitivity and specificity for detecting lung cancer much earlier than current screening methods allow."

To detect lung cancer, the immune-system signals are evaluated, in similar manner as the blood tests are taken to detect HIV virus.

Hanash further said "What is going on is that the immune system recognizes the presence of tumor antigens as foreign proteins, even though they are made by cancer cells we all have in us."

The three proteins were found in 51% humans whose lung cancer was developing.   

Hanash also said "This was a critical step that, in fact, a set of antigens do show positivity even before a diagnosis of lung cancer, at a time when subjects don't have any symptoms."

The next procedure would be to check if the blood test used in combination with computed tomography or CT scans can help in early detection of lung cancer.

The researches want to get approval of lung cancer blood test by the U.S Food and Drug Administration.

American Cancer Society acknowledged, “Lung cancer is the leading cause of death in men and the second-leading cause of cancer death in women worldwide.”