Endoscopic ultrasonography in the preoperative staging of gastric cancer - Accuracy and impact on surgical therapy

Background: Endoscopic ultrasonography (EUS) is a standard procedure in the preoperative staging of patients with gastric carcinomas. Herein we present our experience with EUS and discuss the results and their implications for surgical therapy. Methods: A total of 116 patients with histologically confirmed gastric adenocarcinoma were referred to EUS and classified prospectively by the TNM system. The results of the preoperative endosonographic staging were compared with the definitive histopathological results after the operation. Results: The overall accuracy of EUS for determination of the T stage was 78%. The accuracy for the T1 and T2 stages was 80% and 63%, respectively. With 20% and 30%, there was a relatively high rate of overstaging in these cases. The accuracy for T3 and T4 tumors was 95% and 83%, respectively The accuracy of EUS for determination of the N stage was 77%, with a sensitivity of 91% and a specificity of 84%. Resectability was predicted correctly with a sensitivity of 94% and a specificity of 83%. Conclusions: Generally accepted standards for the therapy of advanced gastric carcinomas do not exist. In cases where the therapeutic strategy is surgical exploration, no preoperative staging is necessary. In cases with differentiated treatment strategies, the accuracy of EUS is not sufficient for the selection of patients for endoscopic resection. Its accuracy for submucosal cancer invasion and for the detection of lymph node metastases needs to be further enhanced. If only multimodal therapy is considered, EUS staging seems to be absolutely mandatory. Patients classified preoperatively as TI to T3 can be operated on primarily with sufficient security. In patients where radical resection of the tumor seems doubtful, we recommend that a diagnostic laparoscopy be performed to confirm the diagnosis.