[Problems of the differential diagnosis and classification of liposarcomas (electron microscopy study)].

Ultrastructure of both liposarcomas of different histological types and those with non-verified diagnosis are studied. Liposarcomas are shown to contain a basic complex of ultrastructural features of lipid differentiation and different histological types of these tumours have, in principle, identical features varying in the degree of their expression. The questions of a differential diagnosis of liposarcomas and other tumours can be successfully solved on the basis of the above findings, and even more, a group of liposarcomas with a severe cataplasia that does not have histological analogues may be distinguished. The results allowed to work out an ultrastructural classification of liposarcomas in which the degree of cataplasia is directly taken into account.