[Ultrastructure of human embryonal liposarcoma].

Human embryonal liposarcoma and embryonal fat have been studied histologically, in semithin sections, and electronmicroscopically. Specific ultrastructural features of embryonal liposarcomas allowing them to distinguish from other tumours are as follows: the presence of lipid vacuoles varying in size, number and structure, small mitochondria with dense matrix, specific filamentous apparatus, basal-like material in plasma cell membrane and in the intercellular space cytoplasmic sprouts forming peculiar "pockets" and general cell architectonics. Similarities and differences in the ultrastructure of embryonal liposarcomas and embryonal fat are found.