Modeling of long-term screening for lung carcinoma

BACKGROUND. Results from the Mayo Lung Project (MLP), a randomized clinical trial for the early detection of lung carcinoma, were interpreted as proof that the early detection of lung carcinoma by chest X-ray does not reduce the mortality from this disease. Recent analysis of extended follow-up data from the MLP subjects found that after approximately 20 years there still was no apparent difference in lung carcinoma mortality between a study grou p and a control group. METHODS. To view this result within context, the authors utilized a previou sly published simulation model of the MLP, with parametric values that were estimated at the time of the original publication based on the data collec ted by the MLP. RESULTS. The model produced predictions of the extended follow-up statistic s that were found to be consistent with the data published in the prior stu dy. The authors believe this provides long-term validation for the model. C onversely, the same model demonstrated that had the study subjects been scr eened annually for the extended follow-up period, the difference in mortali ty would be noticeable, even with the low sensitivity of chest X-ray detect ion. CONCLUSIONS. The results of current study strongly suggest that long-term s creening with chest X-ray results in a reduction in lung carcinoma mortalit y. The limited extent of this benefit is the result of the low sensitivity of chest X-ray as a screening tool. (C) 2001 American Cancer Society.