Malignant fibrous histiocytoma in a 9-year-old girl.

A case of malignant fibrous histiocytoma in the left temporoparietal region of a 9-year-old girl is reported. The tumor was cystic with a mural nodule. Microscopically, the tumor focally infiltrated the leptomeninges sparing the dura mater, and was composed of glial fibrillary acidic protein-negative cells suspended in a rich meshwork of reticulin fibers. Electron microscopy showed the presence of extensive thin processes on the cell's surface and lysosomal-like inclusions in the cytoplasm. No basal lamina was present around the cells. The clinical and pathologic features of this case were compared with those of previous cases described in the world literature.