Which marker is included in the IHC panel for primary neuroendocrine lesions (general)?

• A. Chromogranin
• B. PTH
• C. SF-1
• D. HCG

Answer: (A)

Immunohistochemistry for neuroendocrine lesions relies on markers that come from the secretory machinery of neuroendocrine cells. Chromogranin A sits inside the secretory granules of these cells and is a classic positive marker used to confirm neuroendocrine differentiation in tumors. In practice, this marker is routinely included in the IHC panel to help identify neuroendocrine lineage and distinguish these tumors from non-neuroendocrine ones, often alongside other neuroendocrine markers like synaptophysin. The other markers point to different tissues—PTH to parathyroid, SF-1 to adrenal/gonadal steroidogenic tissue, and HCG to placental or certain germ cell tumors—so Chromogranin A is the one that best fits a general neuroendocrine panel.