Role of Endoscopic Ultrasound in selecting superficial esophageal cancers for Endoscopic resection.
BACKGROUND: Endoscopic submucosal dissection (ESD) is one of the curative treatment options for superficial esophageal cancer with minimal risk of lymph node metastasis. Prior to 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. METHODS: We 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 to clinical stage evaluated by EUS. RESULTS: Among 532 cases, 321 cases were superficial esophageal cancer (pTis, 42; pT1a, 115; 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%. In multivariable analysis, tumor size (>2 cm), poor differentiation, protruding gross type, and use of conventional EUS (vs. miniprobe) were associated factors for overstaging of pTis-T1a. CONCLUSIONS: Prediction accuracy of EUS for selecting the mucosal esophageal cancer that can be treated with ESD was favorable. Target lesions with large size (>2 cm), poor differentiation, protruding morphology were related to T overstaging, and precaution should be taken in evaluating clinical stage for cancers with those conditions. Furthermore, miniprobe EUS provides higher accuracy for squamous esophageal cancers confined to mucosa.