Primary pancreatic paraganglioma harboring lymph node metastasis: A case report

Figure 3 Histological and immunohistochemical examinations of the resected tumor. A: Hematoxylin-eosin staining shows the classic Zellballen pattern; B: The sustentacular cells of tumor tissue are positive for S-100 protein; C: The neoplastic cells are positive for chromogranin A; D: The neoplastic cells are positive for synaptophysin; E: Positive staining for CD34 in the surrounding fibrous septa highlights abundant vascularization inside the septa; F: Ki-67 assessment (+, 2%).