Primary orbital primitive neuroectodermal tumour with immunohistochemical and electron microscopic confirmation

Abstract
Presentation of two cases of orbital primitive neuroectodermal tumour. Microscopically, the tumours consisted of poorly differentiated cells with dark, oval to irregular nuclei, prominent nucleoli, scant cytoplasm and numerous mitoses. The clinical picture, histopathology, electron microscopy and immunohistochemical findings of these cases are presented in this communication. Also, the histogenesis of such orbital neoplasms in relation to central nervous system is discussed.