Evaluation of Siewert classification in gastro-esophageal junction adenocarcinoma: What is the role of endoscopic ultrasonography?

BACKGROUND: Preoperative assessment of gastro-esophageal junction (GEJ) adenocarcinoma stage and its location according to Siewert are essential for planning the therapeutic approach. The present study was aimed at analyzing the utility of endoscopic ultrasonography (EUS) in evaluating GEJ adenocarcinoma stage and whether this modality added to EGD improves assessment of Siewert type. METHODS: The results of 51 patients studied by EGD plus EUS (EGD/EUS group) were compared with the results of 54 patients studied by EGD only (EGD group). RESULTS: A differentiation of pT1 tumors was attempted by measurement of the tumor length using 4 cm as a criterion. This goal was not achieved because of a high rate of advanced tumors less than 4 cm (sensitivity and specificity were 81.3% and 34.2%, respectively). Conversely EUS ability in pT1 assessment was very reliable (92%). The accuracy in defining the Siewert type was 72.5% and 64.8% for EGD/EUS and EGD groups, respectively (P = 0.394). Some difficulties in distinguishing between type II and III tumors were observed in both groups with an extremely low specificity (44%) in classifying type II tumors by EGD group. CONCLUSIONS: EUS seems to be essential in differentiating pT1 from advanced tumors. It shows an accuracy in defining the Siewert type of 72.5%, with some difficulties in distinguishing from type II and III tumors.