An investigation of 11 caaes of granular cell turnor clinicopathologically was performed . Microscopically
the tumors were composed of large cells with abundant granular eosinophilic cytoplasm. The tumor cells had indiatinct cell borders and were arranged in nests and cords. Under elcetron microscope
there were abundant autophagic vacuoles in the cytoplasm of tumor cells. lmmunohistochemical staining showed that all cases were positive for S - 100 protein and NBE
but negative for Deamin
Myoglobin and a - 1 AT. The rosults indicated that the granular cell tumor orginated from Schwann cells.