Role of endoscopic ultrasonography in preoperative staging of gastric carcinoma.

Background: Preoperative staging of tumour extent in upper gastrointestinal malignancy greatly facilitates planning of therapy. The present study was undertaken to see whether preoperative endoscopic ultrasonography (EUS) accurately predicts the tumour stage in gastric carcinoma.
Methods: Endoscopic ultrasonography was performed preoperatively on 112 patients with gastric cancer. All 112 patients underwent surgery. The results of EUS were compared with postoperative histological staging.
Results: Endoscopic ultrasonography was correct in determining the primary tumour (T) and regional lymph node (N) staging in 83.0% and 64.2% of patients, respectively. EUS was correct in determining the absence of lymph node metastasis in 87.5% but was not reliable in determining metastasis in one to six regional lymph nodes (N1) and metastasis in seven to 15 regional lymph nodes (N2) stages; (61.5% and 33.3%, respectively). Of 26 patients with N1 stage, 10 had false negative results, whereas 11 patients in stage N2 were diagnosed endoscopically as stage N1. The sensitivity and specificity were 67.2% and 89%, respectively. The actual resection rate (75%) was almost identical to the rate predicted preoperatively by EUS (78%).
Conclusion: Endoscopic ultrasonography staging is the most accurate method for discriminating between potentially resectable (tumour invading lamina propria or submucosa (T1) to tumour that penetrates the serosa (visceral peritoneum) without invading adjacent structures (T3)) and potentially non-resectable (tumour invading adjacent structures (T4)) cases of upper gastrointestinal cancer.