'Better' lung cancer biomarker could aid early detection

Lung cancer causes more deaths than any other cancer worldwide, and late diagnosis often contributes to high mortality rates. But now, researchers think they may have a key to spotting the disease earlier: a protein that's present in high levels in lung cancers and can be detected in the blood.

According to a study published in the American Association for Cancer Research (AACR)'s journal Clinical Cancer Research, a high level of a protein called isocitrate dehydrogenase (IDH1) in the blood can signify non-small cell lung cancers. While other biomarkers currently help diagnose the disease, Dr. Jie He, director of the Laboratory of Thoracic Surgery at the Peking Union Medical College and Chinese Academy of Medical Sciences in Beijing, told the journal they're not very sensitive, leaving an opening for better biomarkers--like IDH1.

He and his colleagues collected blood samples from 943 patients with NSCLC and 479 healthy participants for the study, conducted from 2007 to 2011 in the Cancer Institute and Hospital of the Chinese Academy of Medical Sciences. Researchers measured levels of IDH1, as well as existing biomarkers CEA, Cyfra21-1 and CA125, in patients' blood, later dividing samples into a training set and a test set to evaluate IDH1's efficiency as a detector.

Results showed that IDH1 could be detected in the blood of lung cancer patients with 76% sensitivity; that number jumped to 86% when researchers combined IDH1 with the three other existing biomarkers used in the study.

He said biomarkers like IDH1 will prove especially important as the population ages and, in turn, lung cancer's prevalence increases. It's also possible that the protein could be used to spot precancer, "but further studies are required to address that possibility," he said. For now, He and his colleagues intend to conduct a multi-center clinical trial to further validate IDH1 as they study the molecular mechanism that boosts the protein in lung cancer patients.

- read more from the AACR