Endoscopic Ultrasound in Detailed T-staging of Upper GI Malignancies in Vitro

- EUS Examination After the surgery, the specimen is filled with 0.9%NS (normal saline ) without cut open，and put into a container filled with 0.9%NS before fixation in formalin. EUS will be performed on the resected specimen.The endoscopy move from the distal to proximal side along the longitudinal axis of stomach, evaluate the invasion of gastric wall, and mark the deepest point with sutures under the EUS guided. The images were stored .

EUS images the are reviewed by two endoscopists. They are asked to stage the tumor according to the AJCC(American Joint Committee on Cancer) staging system (7th edition) , assign a level of confidence to the staging, and score the quality of the EUS image .

• Histologic Preparations and Examination Carcinoma invasion into each layer of the gastric wall is diagnosed by an experienced pathologist (L.ZW) who is unaware of the findings of the EUS imaging. The marked section will be assessed separately.
• Data analysis The diagnosis between the pathologic findings and EUS prediction will be compared. Whether the marked point was the deepest in pathologic findings is recorded. And the histological section and the EUS image of the marked point is compared.