The four different types of EGC. (A) PMD adenocarcinoma, it was composed of moderately differentiated type only; (B) MMD type adenocarcinoma, the moderately components accounting for more than 50%; (C) MPD type adenocarcinoma, the poorly components accounting for more than 50%; (D) PPD adenocarcinoma, it was composed of poorly differentiated type only. HE (the method of staining), ×400 (internal scale). EGC, early gastric cancer; PMD, pure moderately differentiated; MMD, mixed predominantly moderately differentiated; MPD, mixed predominantly poorly differentiated; PPD, pure poorly differentiated.