High Rate of Lymph-Node Metastasis in Submucosal Esophageal Squamous-Cell Carcinomas and Adenocarcinomas - Bollschweiler, E; Baldus, S E; Schröder, W; Prenzel, K; Gutschow, C; Schneider, P M; Hölscher, A H (Endoscopy, 2006)