Advances in sputum analysis for screening and early detection of lung cancer.

BACKGROUND Screening for lung cancer using currently available techniques is not effective in reducing mortality from the disease. METHODS Archived sputum specimens and clinical data linking specimens to lung cancer outcomes from prior screening programs have been reexamined to evaluate altered gene expressing, including specific oncogene activation and tumor suppressor gene deletion, as well as genomic instability and abnormal methylation. RESULTS Several of these tests allow determination of a molecular diagnosis of cancer years before clinical presentation. CONCLUSIONS These sputum tests provide an impetus to reconsider screening for lung cancer. Prospective trials are required to confirm test performance characteristics, and management and intervention strategies must be developed that are appropriate to the stage at which lung cancer is diagnosed.