ENDOSCOPIC ULTRASOUND STAGING CRITERIA FOR ESOPHAGEAL CANCER

Background: Malignant esophageal masses can be staged with endoscopic ultrasound (EUS) using the TNM staging classification. Several criteri a for differentiating between intraesophageal (T1-2) and extraesophage al (T3-4) masses have been described, but highly accurate staging rema ins difficult. Methods: This is a blinded evaluation of four specific EUS criteria in 24 patients with esophageal malignancy who underwent e sophageal resection after neoadjuvant chemotherapy. Radial EUS was use d to evaluate the first 12 patients and curved linear EUS was used in the second half of the group. Using the histology of the resected spec imens, the sensitivity, specificity, and accuracy of the EUS criteria after chemotherapy were determined for predicting intraesophageal or e xtraesophageal invasion. Results: There was no difference in the accur acy rates with radial or linear EUS. Two ultrasound criteria, muscular is disruption and irregular mass border, were found to have low accura cy rates (44% and 50%). The maximal thickness (overall or extraesophag eal) of the esophageal mass was found to be highly accurate (79% and 8 7%) in predicting intraesophageal or extraesophageal extension. pT3-4 masses had a thickness of 16.0 +/- 2 mm, significantly greater than pT 1-2 masses, 8.2 +/- 1 mm (p < .01). Using receiver operator characteri stics (ROC) curve analysis, mass thickness was found to be more accura te (91% and 94%) than a subjective assessment of staging (73%) (p < .0 7). Conclusions: The EUS measurement of a malignant esophageal mass ma ximal thickness can accurately predict extraesophageal extension.