Diagnosis of Invasion Depth
Gastric cancer arises within the mucosa and infiltrates down to the submucosa. The risk of lymph node metastasis of T1a, AC (adenocarcinoma) is rare. However, the incidence of lymph node metastasis of T1b, SM, AC is around 15 %. Therefore, accurate diagnosis of invasion depth is important for treatment decision making. In this chapter, key points for accurate endoscopic diagnosis of invasion depths are described.