Fig. 2

Histological and immunohistochemical features of composite intestinal adenoma-microcarcinoid, mimicking invasive carcinoma. a Low power magnification shows adenomatous glands with minute microcarcinoid component (black arrows, ×40). Arrow heads indicate adjacent carcinomatous area. b High power magnification reveals endocrine cell nests with angulated shape and infiltrative growth pattern, harboring the potential for misdiagnosis as carcinoma invasion (×200). c Immunohistochemical staining for synaptophysin shows diffuse cytoplasmic reactivity in microcarcinoid component (×200). d The microcarcinoid component displays focal positivity for chromogranin-A on immunostaining (×200)