Letters Section Editor: Robert M. Golub, MD, Senior Editor.
In Reply: The comments of Drs Gopal and Budoff concern the use of cardiac CT for lung cancer screening, an indication that we did not examine. We acknowledge the important additional strengths of the National Lung Screening Trial design highlighted by Drs Berg and Aberle.
Dr Spaggiari and colleagues misstate our findings: we did not observe a reduction in lung cancer mortality in association with CT screening. The theory that there exists “indolent” lung cancer is an explanation for our findings, not one on which our analysis is based. Changing patterns of competing risks affect projections of the length of time an individual will be “at risk,”1,2 but in our analysis, the length of time each individual was at risk was known. Our mortality model was validated in women after we raised a concern about this issue.2,3 Further refinements to our predictions of stage-specific or surgical outcomes, or to our adjustments of the Moffitt data, are unlikely to have altered our conclusions, given our models' overall validity. Our article provided a detailed explanation for our exclusion of the first-year mortality data. There was only 1 death from lung cancer observed compared with 9.5 predicted in the first year, despite the inclusion of the risk attenuation factor in that year. We attribute this finding to a healthy volunteer bias that would be expected to decay rapidly over time.
Bach PB, Jett JR, Pastorino U, Tockman MS, Swensen SJ, Begg CB. Computed Tomography Screening for Lung Cancer—Reply. JAMA. 2007;298(5):513-516. doi:10.1001/jama.298.5.515