Decision tree sensitivity analysis for cost-effectiveness of chest FDG-PET in patients with a pulmonary tumor (non-small cell carcinoma)

Decision tree analysis was used to assess cost-effectiveness of chest FDG-PET in patients with a pulmonary tumor (non-small cell carcinoma, ≦ Stage IIIB), based on the data of the current decision tree. Decision tree models were constructed with two competing strategies (CT alone and CT plus chest FDG-PET) in 1,000 patient population with 71.4% prevalence. Baselines of FDG-PET sensitivity and specificity on detection of lung cancer and lymph node metastasis, and mortality and life expectancy were available from references. Chest CT plus chest FDG-PET strategy increased a total cost by 10.5% when a chest FDG-PET study costs 0.1 million yen, since it increased the number of mediastinoscopy and curative thoracotomy despite reducing the number of bronchofiberscopy to half. However, the strategy resulted in a remarkable increase by 115 patients with curable thoracotomy and decrease by 51 patients with non-curable thoracotomy. In addition, an average life expectancy increased by 0.607 year/patient, which means increase in medical cost is approximately 218,080 yen/year/patient when a chest FDG-PET study costs 0.1 million yen. In conclusion, chest CT plus chest FDG-PET strategy might not be cost-effective in Japan, but we are convinced that the strategy is useful in cost-benefit analysis.