A blood test for certain genes may be more effective at detecting early stage lung cancer than current methods such as CT scans and biopsies, researchers said Monday.
The new test looks at gene expression in the patient's white blood cells, according to lead researcher Anil Vachani, assistant professor of medicine at the University of Pennsylvania.
"We found that the types of genes present in these cells could tell us whether or not cancer was present," Vachani said.
Researchers studied a group of 44 people known to have early stage lung cancer and a control group of 52 subjects of comparable age, sex, race and smoking status.
By comparing various genetic arrays to determine the best combination for detecting cancer, researchers settled on a 15-gene array that showed 87 percent accuracy in detecting lung cancer.
In comparison, CT screening "results in the detection of lung nodules in 20 to 60 percent of subjects," said Vachani.
"This high false-positive rate requires patients to undergo extensive follow-up investigations, such as serial CT scans, PET scans or biopsies," she said.
The study suggested that "lung cancers interact with circulating white blood cells and change the types of genes that are active in these cells," she said, adding that she hoped to expand the research and perhaps pursue a clinical trial of the larger population.
"A diagnostic test that could more accurately determine the risk of cancer in patients would be extremely valuable and have very important economic implications by reducing unnecessary surgery, biopsies and repeated imaging tests," she said.
The research is to be presented at American Thoracic Society's 2008 International Conference in Toronto on Tuesday.