Simple diagnostic test detects genetic signs of lung cancer in a patient's sputum
Detecting signs of lung cancer
DNA coughed up along with phlegm could point to lung cancer, say researchers at the University of Maryland School of Medicine who are developing an inexpensive and non-invasive gene probe to help diagnose early stage lung cancer in current and former smokers.
In the January 15 issue of Clinical Cancer Research, the researchers report that their fledgling test, designed to check whether two genes believed to be tumor suppressors are deleted in cells found in sputum, identified 76 percent of stage I lung cancer patients whose tumors also showed the same genetic loss. Existing sputum "cytology" tests, which look for changes in cell structure, identified only 47 percent of the patients, they say.
While no other simple sputum analysis has found such a high correlation with lung cancer, it is not yet good enough for the clinic, researchers say, and so they are now expanding their test to screen for up to eight genes.
"There is an urgent need to develop reliable early diagnostic biomarkers for lung cancer that can be detected non-invasively, and these two genes look to be great candidate markers for such a test," said Feng Jiang, M.D., Ph.D., assistant professor of pathology at the University of Maryland School of Medicine. "We need to validate our findings, of course, but we have shown that the genetic aberrations seen in sputum reflect the same genetic aberrations found in lung tumors, and that these molecular changes occur before any morphological changes can be seen in a cytology test."