[Problems in the electron microscopic diagnosis of neurosarcomas].

Electron microscopical analysis of 113 cases of neurogenic tumours of the human soft tissues is presented. Ultrastructural signs of neurogenic differentiation are distinguished; neuronal and those of nerve sheaths. The comparison of the ultramorphology of neurosarcomas with that of carcinoids and granular cell tumours is performed. A considerable increase of the proportion of neurogenic tumours among soft tissue neoplasms is noted after the ultrastructural investigation. Differential diagnosis of neurosarcomas and malignant histiocytomas and other tumours at the electron microscopic level is discussed.