FIG. 44.
(1) Homogeneous translucent fibre-cell; (2) cells like unipolar ganglion-cells; (3) giant cell (Osler).
W. Osler has recently described31 to the Philadelphia Neurological Society the structure of certain of these tumors, from which we abstract the following facts: One point referred to is that gliomata sometimes contain larger cells and coarser fibres than are usually shown. The structures are (1) The “spinnen” or spider-cells (characteristic of glioma), which present variations in size; (2) large spindle-shaped cells with single large nuclei (some of the largest cells met with in tumors); (3) cells like the ganglion-cells of nerve-centres, with large nuclei and one or more processes: some are balloon-shaped with single processes; they are larger than the spider-cells; (4) translucent band-like fibres, tapering at each end, without nucleus or granular protoplasm, regarded as a vitreous or hyaline transformation of the large spindle-cells. Klebs (quoted by Osler) holds that the ganglion-like cells are derived from the nerve-cells of the gray matter, “and that in the development of this variety all elements of the nerve-tissue participate.” Osler examined the advancing region of the tumor, and was not able to satisfy himself that the nerve-cells were in process of proliferation. He thinks they are connective-tissue elements. He has seen but two out of five cerebral gliomata which were of small-celled type.
31 “Structure of Certain Gliomas,” Philada. Med. News, Feb. 20, 1886.
The gliomata are subject to fatty degeneration, which usually occurs in the central (older) portions of the mass. The more vascular forms are also peculiarly liable to hemorrhage, which is probably caused in some instances by this process of retrograde metamorphosis. These hemorrhages resemble apoplexies, not only in their clinical features, but also on gross examination. Great care is therefore often necessary at the autopsy to distinguish such a hemorrhage, occurring as it does in a brain-like neoplasm, from one caused by the rupture of a diseased artery. The hypertrophy of the pineal gland, sometimes noted, is caused by the formation of gliomatous tissue. Under the microscope it is necessary carefully to distinguish some forms of inflammatory new formations from the gliomata. We have recently seen, by the courtesy of E. N. Brush of the Pennsylvania Hospital for the Insane, photographs of microscopic sections from the ependyma of the lateral ventricles in a case of general paresis, which showed the structure of this degenerated tissue to be a compound of fibres and cells of marked resemblance to gliomatous tissue.32
32 These micro-photographs were prepared in the laboratory of the State Lunatic Asylum, Utica, New York, by Theodore Deecke.
Sarcomata of the brain are common, as our table shows. In them the cell-elements predominate, both in the large- and small-celled variety. They are malignant and grow rapidly. The form known as alveolar sarcoma, which has a distinct stroma, is to be distinguished from the cancers; which has probably not always been done.
Tubercle, according to Ross, is the most common of all forms of brain tumor. Our table shows 13 cases out of 100, the gliomata and sarcomata being in larger number. Its favorite seat is in the cortex of both the cerebrum and cerebellum: some observations appear to show that it is more common in the cerebellum and mid-brain region than in the fore-brain, and in children than in adults; some of which points distinguish it from the gummata, which are more common in adults and occur anywhere. Tubercle is another form of development from the connective tissues, usually dependent upon a constitutional taint or predisposition: in it the cell-elements have generally undergone a degeneration into an amorphous cheesy mass. It is apt to be multiple and accompanied by a similar deposit in other organs of the body.
True neuromata are probably very rare growths, and it is likely that some tumors which have been described as such are really connective-tissue tumors of a gliomatous nature, in which some of the cell-elements have been mistaken for the ganglion-cells. Obernier33 says that these tumors are small and grow from the gray matter on the surface, also on the ventricular surfaces. They are also found in the white matter. He says they are only found in persons having some congenital or acquired aberration; by which is probably meant some other well-marked neurosis or psychosis. The one hundred tabulated cases afforded no examples of neuromata.