Classification of gastric neuroendocrine tumors and its clinicopathologic significance

Figure 1 Type 1 gastric neuroendocrine tumorsgastrin dependent carcinoid. Histology shows typical carcinoid with trabecular arrangement. Tumor confined to the gastric mucosa, many tumor cells had positive reaction for chromogranin A. ABC method × 450

Figure 2 The hyperplasia and dysplasia of endocrine cells in extratumoral mucosa were found in type 1 gastrin dependent carcinoid. Endocrine cells show positive reaction for chromogranin A. ABC method × 450

Figure 3 Type 2 non-gastrin dependent carcinoid. Tomor invaded the muscularis propria. The hyperplasia of endocrine cells are not distinct. Diffuse synaptophysin in immunostaining of tumors. ABC method × 250

Figure 4 Type 3 neuroendocrine carcinoma. Tumor cells are small and round, mitoses are abundant. Focal necrosis was found. HE × 250 (left). Ultrastructural appearance of the neuroendocrine carcinoma with characteristic secrectory granules. × 28000 (right)

Figure 5 The survival curve of three types of gastric endocrine tumors.