Gastric carcinoid

Medium power view (upper panel) of a biopsy specimen from a gastric nodule showing replacement of the glandular compartment by an infiltrate of uniformed tumor cells. At high power (upper panel) the tumor cells have uniformed small nuclei without mitotic activity, and basophilic cytoplasm. The features are characteristic of a gastric endocrine tumor (carcinoid tumor). Immunohistochemical stains may be helpful to categorize these tumors, which are positive on staining with antibodies to chromogranin and synaptophysin.