University of Pennsylvania researchers have found measurable genetic changes in the white blood cells of people with early-stage lung cancer. The finding could lead to a blood test for lung cancer.

They examined genes expressed by the blood cells of patients with and without lung cancer, and found an array of 15 genes that detected the presence of cancer, with an accuracy of 87 percent. This suggests that lung cancers interact with circulating white blood cells and change the types of genes that are active in them.

CT screening has a high false-positive rate, detecting lung nodules in 20 to 60 percent of subjects. This requires patients to undergo extensive follow-up investigations, such as serial CT scans, PET scans, or biopsies, to rule out lung cancer.

American Thoracic Society News Release