Synaptophysin (Syn)

Synaptophysin is a 38-kDa transmembrane glycoprotein located in presynaptic vesicles and expressed in the presynaptic central and peripheral nervous system, adrenocortical cells, adrenocortical adenoma/carcinoma, adrenal medulla and pheochromocytoma, neuroendocrine cells, etc. It is mainly used for the differential diagnosis of neuroendocrine tumors in carcinomas, Merkel cell carcinoma and basal cell carcinoma, lung small cell carcinoma and lymphoma, pheochromocytoma, ganglioneuroma, paraganglioma and APUD system tumors.