CT or EUS for the initial staging of esophageal cancer? A cost minimization analysis.

BACKGROUND

Patients with advanced (T4 and/or M1) esophageal cancer are offered palliative therapy. Computed tomography (CT) is sensitive for distant metastases but is less sensitive than endosonography for T4 disease and celiac lymphadenopathy. The aim of this study was to determine whether initial CT or endosonography costs less to diagnose advanced esophageal cancer.

METHODS

A decision model compared the costs of the 2 strategies. Sensitivity analysis and threshold analysis were used to identify the most important determinants of the overall cost of identifying advanced disease.

RESULTS

Initial CT is the least costly strategy if the probability of finding advanced disease by initial CT is greater than 20%, if the probability of finding advanced disease by initial endoscopic ultrasound (EUS) is less than 30%, or if the cost of EUS is greater than 3.5 times the cost of CT. However, in our referral center population, endosonography found advanced disease more frequently than CT (44% vs. 13%; p < 0.0001) and the least costly strategy was initial endosonography (expected cost $804 vs. $844).

CONCLUSION

CT remains as the initial staging test of choice in most clinical settings. However, in referral centers, initial EUS may be reasonable, but individualized model inputs must be obtained before reliable conclusions can be drawn.