Role of Endoscopic Ultrasound in Selecting Superficial Esophageal Cancers for Endoscopic Resection

BackgroundEndoscopic submucosal dissection (ESD) is a curative treatment option for superficial esophageal cancer with a minimal risk for lymph node metastasis. Before ESD, accurate clinical staging is important to select the appropriate candidate. We aimed to estimate the practicality of endoscopic ultrasound (EUS) to select pTis and pT1a.MethodsWe included patients with squamous esophageal cancers who underwent surgical resection or ESD between 2005 and 2018. Pathologic reports were reviewed retrospectively, and pathologic T staging was compared with clinical stage evaluated by EUS.ResultsAmong 532 patients, 321 had superficial esophageal cancer (pTis: 42; pT1a: 115; and pT1b: 164). Accuracy rates, sensitivity, specificity, positive predicted value, and negative predicted value for selecting cT1a by EUS were 82.3%, 60.5%, 91.5%, 74.8%, and 84.7%, respectively. The rate of overstaged pTis-T1a was 39.5%. Upon multivariable analysis, tumor size (>2 cm), poor differentiation, protruding gross type, and use of conventional EUS (versus miniprobe) were associated factors for overstaging of pTis-T1a.ConclusionsThe accuracy of prediction of EUS for selecting mucosal esophageal cancer that can be treated with ESD was favorable. Target lesions with a large size (>2 cm), poor differentiation, and protruding morphology were related to T overstaging; precaution should be taken when evaluating the clinical stage for cancers with those conditions. Furthermore, miniprobe EUS provides higher accuracy for squamous esophageal cancers confined to mucosa.