What is the Importance of Immunohistochemistry in Diagnosing PanNETs?

Immunohistochemistry is crucial in diagnosing PanNETs, as it helps in identifying hormone production and differentiating these tumors from other types of neoplasms. Common markers used include chromogranin A, synaptophysin, and specific hormone markers like insulin and gastrin. The expression of these markers helps confirm the neuroendocrine origin of the tumor. Additionally, the Ki-67 index is used to assess the proliferative activity, aiding in the grading of the tumor.