On the Claims of Sick and Wounded Merchant Seamen
Authors: Wm. R. E. Smart
Journal: BMJ (1873)

no doubt that some condition of irritation or exhaustion secures for the brain the first malignant infiltration; but what that condition is, we cannot say.Grisolle believed that cerebral cancer preferentially attacks old people, with brains past their meridian, and on the decline; but that generalisation is not borne out by figures.In forty cases of primary cancer of the brain, recorded by Dr. Ogle, the average age was forty-three years ; in thirty-six cases recorded by Berthier,.it was forty.'When the cancer is secondary, its presence in the brain is more readily understood.The enormous supply of blood which the brain receives, must conduce to the deposition of the materies morbi in it, and must favour its germination and growth, when it is once deposited.Occasionally, also, it reaches the brain by continuity of tissue, and cancer seems to have a special proclivity to run along nerves.In many instances, medullary cancer has been known to spread from the orbit, by the optic nerve, to the brain.Mr. Soelberg Wells gives such a case, in which he removed the contents of the orbit, for a medullary cancer, and in which the optic nerve appeared healthy on section, but was found to contain, between its inner and outer sheath, small diffused patches of cancer-elements.The man died one year and eight months after the operation, when a large cancerous tumour was found in the mid- dle fossa of the skull.When cancer stretches in this way from one organ to another, its elements insinuate themselves amongst the textures of the organ secondarily affected without definite limits; but when, on the other hand, it seizes upon the brain, not by continuity or contiguity of tissue, but by virtue of a previous development elsewhere, or when it occurs in the brain alone in the organism, then it may either appear as a distinct tumour, spherical or lobulated, or as a diffused mass, nowhere sharply demarcated from the normal structures.In whatever shape, and with whatever boundaries it occurs, it destroys the cerebral tissue by preying upon it, and causing its absorption, or compressing it, while it, at the same time, forms attachments to, or perforates any membranes that may be in its vicinity.It presents itself as one, or as several tumours, connected, or distinct from each other.In an interesting case, published by Dr. Manning, there were two tumours, one of the size of a walnut, in the convexity of the hemisphere, and not extending into the white substance ; and another, of the size of an orange, occupying the middle of the hemisphere ; while in three cases reported by Dr. Chap- man, there were several tumours, varying in size from a pea to a walnut, dotted over the cineritious substance of the cerebrum.Then the tumours may vary in dimensions, position, and kind, as much as in number.Occasionally, a whole lobe of the brain is implicated, and again, the adventitious growth is no larger than a pea.Any part of the encephalon may be the site of a cancerous tumour, but the hemi- spheres suffer most frequently, and in these the largest tumours are always seen; for, as Lebert has pointed out, with great justice, a tumour at the base of the brain, and especially near the pons Varolii, or medulla oblongata, is likely to cause death before it has attained any great size, whereas a tumour in the hemispheres may be compatible with life, even when it is of comparatively huge volume.All the different species of cancer are represented in tumours of the brain, except, perhaps, epithe- lioma, which, though met with on the serous layers of the arachnoid,