Staging concepts for gastrointestinal malignancies: the importance of preoperative locoregional T- and N-staging.

Preoperative locoregional staging of gastrointestinal tumors is of special significance for evaluation of resectability that means complete tumor removal without residual tumor (R0-resection). This is especially important within a multimodal therapeutic concept including neoadjuvant therapy of nonresectable tumors. In esophageal cancer above the bifurcation, tumors that are staged T3 or T4 should have neoadjuvant radiochemotherapy in order to achieve a down-staging and increase the chance for a complete tumor resection. Preoperative chemotherapy is further established in esophageal carcinomas below the bifurcation and gastric carcinomas in stage T4. As in pancreatic carcinoma, neoadjuvant treatment has no proven indication. Preoperative locoregional staging mainly concerns the infiltration of retroperitoneal veins, which represents the crucial point for resectability. Concerning carcinomas of the lower GI tract the T- and N-staging is of special relevance for rectal cancer because preoperative radiochemotherapy in T4-stage is an accepted indication. The T- and N-staging of gastrointestinal tumors has important clinical consequences; the demands for accuracy of endosonographic examinations are therefore very high.