Large gangliocytic paraganglioma of the duodenum: A rare entity

Figure 2 Histologic characteristics of the gangliocytic paraganglioma. A: Submucosal location of the tumor (× 40); B: Immunohistochemistry showing S-100 positivity of the spindle cell component (× 40); C: Immunohistochemistry showing positive staining for neuron-specific enolase in three cellular components (× 40); D: Epithelioid cells showing cytokeratin expression. Black arrow indicates ganglion-like cells (× 40); E, F: Nuclear staining with Ki-67 showing a proliferative index of < 2% (but ranged from 5% to up to 20% in other fields). Black arrows indicate epithelioid (paraganglioma-like) cells (E: × 40; F: × 100).