A. Overview of Phase I and II The National Lung Screening Trial (NLST) has been initiated at multiple sites throughout the U.S. with the central objective of defining the potential value of helical CT screening in the detection of early stage lung cancer. Participants are randomized to receive either a conventional PA view chest radiograph, or low dose helical CT scans performed at yearly intervals for a period of three years. The participants have agreed to allow collection of medical records that pertain to subsequent diagnostic studies and treatments initiated as a result of the NLST findings. The present proposal will address the collection and analysis of tissue specimens from participants randomized to the helical CT arm of the trial in two phases as follows: Phase I Aims 1. Pilot testing of urine and serum specimen collection from NLST participants randomized to the CT arm of the trial at UAB, with specimen processing and storage at UAB. IRB approval will be obtained for a large number of eligible participants, explicity stating the Phase I part of the protocol will only collect from 25 participants. This strategy will both ensure that the recruitment and collection processes are perfected, and provide for rapid initiation of collection from a much larger number of subjects in Phase II without delay. 2. Obtain positive and negative control tissue specimens for pilot proteomics analysis experiments. The PI will obtain IRB approval for a separate protocol from that in the first aim that will provide for the collection of bronchoalveolar lavage fluid, serum and urine from individuals shown to have non-small cell lung cancer, as well as a control population. These specimens will be processed and used by the UAB Proteomics Core facility for a series of pilot experiments that will identify differences between the NSCLC patients and controls. These experiments will be useful in the planning and implementation of Phase II. 3. Develop a Phase II component of the biorepository in an iterative process with NLST NCI project directors and associates. The PI will have extensive discussions with the NLST NCI directors regarding the components of the Phase II portion of this contract.