[Electron microscopy as a method of classification of hematopoietic-system tumors].

83 biopsies of lymph nodes and 35 specimens of blood in different types of haematopoietic system oncological involvement were examined electronoptically with a view to finding distinguishing features such as would prove to be better than other methods used in diagnosing the above tumours. In the granulocytic series these proved to be granules though there was a loss of their formation in most of the poorly diagnosable processes. However, it proved to be relatively easy to make use of tests for phagocytosis in myelomonocytes. In the histiocytic series the defining features (phagocytosis and proteosynthesis) proved to be too general in nature to find any relevant use in oncological diagnosis. On the other hand, the rod-like granules of Langerhans' cells proved to be a reliable guide in diagnosing histiocytosis X similarly as the Weibel-Palade granules did in diagnosing endotheliosis. In the lymphocytic series, B series diagnosis can be facilitated by the presence of spatially arranged interdigitations; in the T series interdigitations are either missing or else are arranged in a single plane only. The erythrocytic series is defined by the presence of ferritin while megakaryocytes are defined by the phenomenon of fissure-like communications.--All those features were merely supplementary in nature and could not be used as an independent diagnostic method particularly in view of the small volume of the processed specimens as these did not always contain representative material or else supplied it in a hardly classifiable mixture.