[Primary "muscle" tumors or tumors with a myosarcomatous component of the central nervous system. General review and attempt at classification based on 2 anatomo-clinical observations].

The authors report the first two French cases of primary rabdomyosarcoma of the central nervous system. They then review the literature on muscle tumours or primary myosarcomas of the nervous system of which 29 cases have now been published. From the point of view of morphology and classification, one should distinguish firstly, purely mesenchymatous tumours (rhabdomyosarcomas, leiosarcoma, mesenchymoma) and secondly, composite tumours of connective tissue or spino-epithelial tumours (medullomyoblastomas, neuromyoblastomas, gliomyosarcomas). Their histogenesis occurs from the ectomesenchyme of the neural crests.