[Meningeal fibrosarcomas].

The authors present 4 operated cases of primary fibro sarcomas of the dura mater. Only, a few number of cases had been described in the literature. In Zulch's classification (1957) of 6000 brain tumors, there were 162 cases of sarcoma (i.e. 2,7%) and among sarcoma, 30 cases of fibrosarcoma of the dura mater. In according with the WHO classification of brain tumors (Zulch, 1979), the primary fibrosarcoma of the dura mater takes place in the group of meningeal sarcomas with the polymorphic cell sarcoma and the primary meningeal sarcomatosis. The pre-operative diagnosis is difficult, because neither clinical data, neither neuroradiological findings are characteristics. The prognosis of the patients with this tumor is poor, however some examples are known to have had a long post-operative survival. The association: complete surgical extirpation--post-operative radiation appears like to best treatment. Pathological examination showed in our four tumours, the features of fibroblastic sarcomas with haemorrhagic zones and foci of osteoid metaplasia. The ultra-structural study in 2 cases, confirmed the specificity of tumoral cells which did not display any histological similarity to the arachnoïdal cells. In one case, a myofibroblastic differentiation was evident, and thus, confirmed the plasticity of tumoral fibroblastic cells. The immuno-histochemical reaction of GFAP revealed reactive astrocytic areas in one case inside the immuno-histochemical sarcomatous tissue.