Immunohistochemical Tumor Differentiation

Type of Filament	Tissue Origin	Tumor Type
Keratin,Cytokeratin	Epithelial Cells	Carcinomas(Squamous and Adeno) Synovial and epithelial sarcomas Non-Seminoma Germ Cell Tumors Some neuroendocrine carcinoma Choroid Plexus Tumors Some leiomyomas
Vimentin	Mesenchymal Cells Macrophages Endothelial Cells	Sarcomas (all types) Malignant Fibrous Histiocytoma Melanoma Seminoma Schwannoma, meningioma Occasionally in some adenoca
Desmin	Muscle Cells	Skeletal, smooth, or cardiac muscle sarcomas
Glial fibrillary acidic protein (GFAP)	Glial Cells	Astrocytomas, gliomas Choroid plexus tumors, some oligodendrogliomas, Schwannomas, neurofibromas, some salivary gland mixed tumors
Neurofilament	Neurons or neural crest	Neuron-derived CNS tumors Neural crest-origin tumors: Neuroblastoma, retinoblastoma, medullablastoma Neuroectoderm-derived tumors: Pheochromocytoma, lung, and GI tract carcinoids, some small cell lung ca, Merkel Cell tumor, parathyroid adenoma, pancreatic islet cell tumors, paraganglioma
S-100 Protein	Central Nervous and Peripheral Nervous System Also from pancreas, breast, thyroid, gallbladder, liver, melanocytes	Central Nervous System and Peripheral Nervous System Tumors Melanomas, histiocytosis X, Cholangiocarcinoma, pancreatic duct and islet cell carcinomas, other various carcinomas
Epithelial Membrane Antigen	Milk fat globule membranes	Same as keratin
Neuron Specific Enolase	Neurons	Gliomas, Carcinoids, small cell (lung), neuroblastomas, neuroendocrine, melanoma, meningiomas, schwannomas
Melanoma Specific Antibody(HMB-45)	Melanocytes	Benign and malignant tumors of the melanocytes
Leukocyte common antigen	B- and T- cells	Leukemias, and Lymphomas
Factor VIII related antigen	Endothelial Cells	Angiosarcomas, Kaposi's Sarcoma
Myoglobin	Skeletal Muscle	Rhabdomyosarcoma
Muscle-specific actin	Muscle all types	Muscle derived sarcomas
Chromogranin	Neuroendocrine	Pheochromocytoma, carcinoids, paragangliomas