Goblet Cell Carcinoid, Group B
Goblet cell carcinoid, Group B (Adenocarcinoma ex GCC, signet ring-cell type). The image shows tumor cells with predominant signet ring cell features arranged haphazardly in the lamina propria. They have hyperchromatic nuclei with moderate cytologic atypia. Immunohistochemically, both Group A and Group B GCC's show reactivity for neuroendocrine markers, including chromogranin and synaptophysin. The normal membranous staining for beta-catenin is preserved. p53 is negative. MUC1 is negative where as normal MUC2 staining pattern is preserved. Ki-67 proliferative index is low.