Cost effectiveness of chest CT in T1N0M0 lung cancer.

The role of chest computed tomography (CT) in the evaluation of clinically staged T1N0M0 lung cancer is controversial. Using quantitative methods of decision analysis and data already available in the medical literature, the authors show how the clinical utility and cost effectiveness of chest CT are dependent on several variables: the prevalence of mediastinal metastases in T1N0M0 patients; the sensitivity and specificity of chest CT; patient life expectancy; and the morbidity, mortality, and monetary costs of CT, invasive mediastinal biopsy procedures, and curative surgical resection. When average values for these variables are used in the analysis, routine chest CT adds about 1 day to a T1N0M0 patient's life expectancy and saves about $150 per patient. Furthermore, a true-positive yield of 6% is sufficient for chest CT to be both clinically useful and cost saving, provided CT is readily available.