Diagnosis of superficial esophageal squamous cell carcinoma invasion depth before endoscopic submucosal dissection

Endoscopic submucosal dissection (ESD) is a widely accepted procedure for superficial esophageal squamous cell carcinoma (SESCC) limited to the epithelium or lamina propria mucosae (EP/LPM). We aimed to compare the efficacy of endoscopic ultrasonography (EUS) and magnifying endoscopy with narrow band imaging (ME-NBI) for predicting the tumor invasion depth in patients with SESCC. Specifically, we evaluated the ability of these examinations to distinguish EP/LPM from SESCC invading the muscularis mucosae or superficial submucosa (MM/SM1) and more deeply invasive lesions before ESD. We retrospectively analyzed a database of all patients with SESCC who had undergone both EUS and ME-NBI for pretreatment staging and ESD resection at Hiroshima University Hospital between September 2007 and June 2015. The clinicopathologic characteristics of SESCCs were classified according to the Japanese Classification of Esophageal Cancer. A total of 174 lesions in 174 patients were included: 124 (71%) EP/LPMs, 35 (20%) MM/SM1s, and 15 (9%) SESCCs invading the mid submucosae (SM2). The sensitivity of EUS and of ME-NBI in distinguishing EP/LPM from MM/SM1 and more invasive lesions was 72% and 83%, respectively. The accuracy of EUS and ME-NBI in distinguishing EP/LPM from MM/SM1 and more invasive lesions was 70% and 82%, respectively. Sensitivity and accuracy of ME-NBI in distinguishing EP/LPM from MM/SM1 and more deeply invasive SESCCs is significantly higher than those of EUS (P = 0.048 and P = 0.017, respectively). ME-NBI may be more useful than EUS for the determination of SESCC invasion depth before ESD.