Endosonography of high-grade intra-epithelial neoplasia/early cancer.

Endosonography (EUS) is frequently used for staging of early malignant gastrointestinal lesions. High-grade intra-epithelial neoplasia (HGIN) and mucosal cancer have a very low risk for lymphatic metastasis and therefore are suitable for endoscopic therapy. In HGIN and early oesophageal and gastric cancer, high-frequency miniprobes can provide detailed imaging of the different layers. However, diagnostic accuracy differentiating between mucosal and submucosal disease is not sufficient, and therefore (diagnostic) endoscopic resection should be performed in all localisable lesions to detect submucosal cancer at risk for lymph node metastasis. EUS for lymph node staging is considered to be the method with the highest accuracy, especially compared with computed tomography.