Deepthi Mani

MD

University of Washington

MPH student

NLST (Learn more about this study)

NLST-230

Jul 19, 2016

Mortality benefit from lung cancer screening

The Nation Lung cancer screening trial (NLST), a randomized multi-center study, comparing 3 annual low dose helical computed tomography (LDCT) with chest radiography in the screening of 53,454 older current and former heavy smokers for early detection of lung cancer reported a 20% reduction in lung cancer mortality in the LDCT group.The U.S. Preventive Services Task Force (USPSTF) has endorsed annual low dose helical CT as a screening tool for lung cancer, giving it a grade B recommendation, denoting moderate certainty that the net benefit from screening is moderate to substantial. The modest 20% mortality benefit from NLST could however be a potential under-estimation of the benefit of screening as this mortality measure for the trial period averages the almost null reductions in the time period immediately following screening and the larger, divergent mortality reductions that emerge in the ensuing years with ongoing screening. Time specific mortality ratios to address the timing and extent of mortality reduction could give a more accurate picture of the mortality benefit from screening. The precise estimation of mortality is relevant for calculation of cost benefit ratios of screening and influences the decision making process of clinicians and at risk individuals who consider screening. The current project will focus on re analyzing the mortality data from NLST through time specific measures.