[Ultrastructural study of 36 lymph node sites of Hodgkin's disease]

Abstract

The authors report their ultrastructural findings of 36 involved lymph-nodes in Hodgkin's disease (HD), before any treatment. More than 400 tumour cells were studied. An analytical study was carried out on the different aspects presented by the nuclei (uni or multi-lobated); the nucleoli (compact, reticulate or dispersed); and the cytoplasm (immunoblastic, complex, intermediate). No cellular structure evoking phagocytic activity with digestion, and consequently an eventual histiomonocytic origin, could be detected even on serial sections. The presence of lipid inclusions, sometimes of glycogen, as well as certain peculiar structures are described and discussed. The ultrastructural aspects could be easily correlated with the different types of tumour cell described in HD using light microscopy. The various kinds of cells which could could be detected in the same lymph node, may correspond to a real tumour cell lineage, consisting, firstly, of a cell of immunoblastic type with a mono- or bilobated nucleus, then an intermediate type with a bilobated or multisegmented nucleus, and finally a complex cell type with a multisegmented nucleus. The lacunar cells are characterised by a fragile hyaloplasm, without cellular organelles at their periphery, these being concentrated around the nucleus. This special organisation explains the aspects observed in light microscopy. However, no explanation could be offered to understand this particular aspect of the cytoplasm. The ultrastructural characteristics of the Reed-Sternberg cells and their variants did not allow a precise cellular origin to be proposed. The absence of phagolysosomes pleads against a histiocytic origin. However their similarity of the interdigitated reticular cells did not seem sufficient to propose this origin. The likeliness of the cytoplasm of cells with mono- or bilobated nuclei with that of immunoblasts, constitutes the most interesting morphological feature. This fact, associated with the appearance of immunoblasts similar to Reed-Sternberg cells of infectious mononucleosis, suggests a lymphoid origin. The study of the reactive cells around the tumor cells did not allow any consequences to be drawn. One could simply note that the Reed-Sternberg cells and their variants were surrounded by lymphocytes, forming a kind of crown. No etiological agent could be detected. These data are compared to those of other publications, and discussed. This ultrastructural study, therefore, does not offer the solution to most of the questions which still remain to be answered as to the origin of the Reed-Sternberg cells.(ABSTRACT TRUNCATED AT 400 WORDS)