HISTOPATHOLOGIC STUDIES OF OLIGODEN-DROGLIA CELLS IN THE GLIOMAS

Summary and Conclusion I hare studied on the appearances of the oligodendroglia in various kinds of glioma with hematoxylin-eosin stain and specific silver impregnations, well with forethought that the specific impregnation for oligodendroglia is imperfect. Oligodendroglia represents generally an unimportant element in the gliomas. Especially, non-neoplastic oligodendroglia cells are so few that they seem right negligible as compared with many non-neoplastic astrocytes existing in the gliomas. There are no oligodendroglia cells in the epithelial ependymoma, and a few non-nesplastic oligodendroglia cells in the astrocytoma, in the spon-gioblastarna polare and in the modullsblastoma. In other gliomas, there are both of the non-neoplastic and the nesplastic oligoden-draglia cells, the latter being always more numerous than the former If oligodendroglia cells are demonstrated with specific impregnations only in a part of a tumor, there are always to be found more numerous oligodendroglia-like cells stained with hematoxylin-eosin in the same place. On the other hand, where oligodendroglia-like cells are stained with homatoxylin-eosin, there are not always true oligodendraglia cells demonstrable with specific impregnations. This is not necessarily due to the imperfection of the specific impregmatopm. As is assumable from the fact that some of the minute or small astrocytes constituting an astrocytxns are easily mistaken for oligsdendroglia cells in case of hematoxylin-eosin stain, the oligodendroglia-like cells stainable with hematoxylin-eosin but unimpregnable specifically may once be the minute or small astrocytes. It is my impression that almost all non-neoplastic oligo-dendroglia cells in a glioma do not fail to be impregnated with specific impregnation just as in case of the oligodendroglia in the normal brain tissue. The neoplastic oligodendroglia cells are not always impregnated with the specific impregnation. Considering the fact that the number of oligodendroglia impregnated specifically and that of oligo-dendroglia-like cells stained with hematoxylin-eosin run parallel to each other and that the former cells tend to be present in groups. most of the latter cells may b: atypical or undifferentiated oligodendroglia cells. For the same reason, most cells constituting an oligoden-droglioma may not unlikely belong to neoplastic oligodendroglia cells. And these cells are stained with specific impregnation in an oligodendroglioma sheerly in a much larger number than in the other gliamas. The results of my study are to be summarized as follows: 1)  Almost all of the constituent cells of the oligodendroglioma may be neoplastic oligodendroglia cells. 2)  Non-neoplastic oligocendroglia cells, though few in number, are found in all gliomas except for the epithelial ependymoma. 3)  In the cellular ependymoma many neoplastic oligodendroglia cells are distributed pretty evenly throughout the tumor. It may not be unreasonable to admit a tumor of the transitional type between the oligodendroglioma and the cellular ependymoma. 4)  In some of the glioblastoma multiforme, there are found neoplastic oligodendroglia cells here and there groupwise. 5)  In other gliomas, especially immature gliomas, it is possible that neoplastic oligodendroglia cells are contained in variable numbers. 6)  The difference between the number of oligodendroglia cells in hematoxylin-eosin stain and that in specific silver impregnations seems to be due to the circumstance that the minute or small astrocytes and undifferentiated glia cells, especially undifferentiated oligodendroglia, are mixed in the gliomas in varying number.