CHAPTER VIII.

Lymphadenoma; its Clinical and Anatomical Characters-Psammoma; its Usual Seat, Structure, Innocency, and Rarity.

LYMPHADENOMA.-Amongst the various new formations to which surgeons have in former times given the common name "encephaloid cancer," perhaps none is still so seldom recognised as that to which the name "lymphadenoma" has been given by modern pathologists, to signify the close correspondence between the microscopic structure of this growth and that of the follicular portion of a lymphatic gland, known as the "adenoid tissue of His." It is only quite recently that special attention has been called to this variety, in England more especially by Dr. Sanderson and Dr. Murchison, and in France by MM. Cornil and Ranvier. The disease may be shortly described here as one in which soft infiltrating tumours of various sizes are scattered through the several organs and tissues of the body in a manner precisely resembling many of the soft sarcomas and carcinomas already noticed, but made up of very different and sufficiently characteristic elements.

Usually commencing in an enlargement of lymphatic glands, and often limited to such hypertrophy, many glands being matted together to form one vast mass, the morbid structure is often met with invading the internal viscera-as the spleen, lungs, liver, and kidneys-and even the muscles and bones are not always exempt from the disease. The tumours are usually of a grayish- or yellow-white colour, sometimes as distinctly encapsuled as a lymphatic gland, but in other cases passing gradually into the structure of the part in which they are seated, varying in size from a miliary

granule to that of a cocoanut, or larger, and in consistence from a creamy pulp to that of a cirrhosed liver, and yielding a more or less abundant milky juice. This juice, when examined microscopically, is almost sufficiently diagnostic, for it contains none of the cell-forms already described as occurring in carcinoma or the commoner varieties of sarcoma, but only small, spherical, faintly granular corpuscles, precisely resembling leucocytes or the white corpuscles of the blood. With these there may be free granules and a few somewhat larger distinctly nucleated cells. It is, however, only when thin sections are taken from bits of the tumour hardened in chromic acid solution that the true structure is seen.

Sections thus prepared show a fine homogeneous-looking network, enclosing in its meshes, either singly or in small clusters, the pale spherical corpuscles seen in the juice. In

FIG. 18.

FIG. 18. Very thin section of a lymphadenomatous tumour pencilled out under water, showing the delicate irregular network and a few remaining corpuscles. Magnified 220 times.

the early stages nuclei are to be distinguished in certain of the angles of this network just as in the stroma of a lymphatic

gland; but in the later stages-those generally presented to the surgeon-the network is formed of stouter fibrils, in which the nuclei are less apparent. The structure then closely resembles that of a lymphatic gland in a condition of irritative induration; and it is this structure, with the fibrillated stroma more or less largely developed, that forms the bulk of these tumours (Plate IV).

To see this stroma distinctly it is necessary to pencil out a very thin section under water. When the corpuscles which obscure the view have been thus mostly chased away, the irregular network is clearly visible. In the foregoing sketch (fig. 18) this has been done, and the thickened network shown is a fair sample of the usual structure of these tumours, although the absence of nuclei from the angles of the meshes takes away the most characteristic element and that which specially distinguishes this growth from the small round-cell sarcoma. The latter, however, is so seldom accompanied by any notable fibrillation of its stroma, that a distinct smallmeshed network is of itself sufficient to stamp the lymphadenomatous character of the growth presenting it. Whether these lymphoid formations originate in the proliferation of ordinary connective tissue, or whether they consist of hyperplasia of pre-existing adenoid tissue, is a question difficult to decide. In all their clinical features of rapid infiltrating growth, and implication of adjacent glands, as well as the formation of similar swellings in remote parts, they are probably as malignant as the most virulent carcinoma, and need the same treatment. The tumours differ from the similar masses present in leukæmia only in the absence of any obvious alteration in the blood. The histological structure is the same in both cases, but there is no notable excess of white corpuscles in the blood of a patient with lymphadenoma, as there is in so marked a degree in leukæmia.

PSAMMOMA. The tumour to which Virchow has given this name, from the circumstance of its containing "brain sand" (aμμos, sand), is sometimes classed with the sarcomata, although not much resembling any other member of this

group; and it is inserted here more on account of its rarity and want of recognition by English writers, than because it presents many features likely to be taken for those of cancer. The growth is found usually springing from the membranous envelopes of the brain and spinal cord, or in the choroid plexus, and it derives its peculiar aspect from the fact of its holding amidst its other elements a varying proportion of the curious corpora amylacea, which, when infiltrated with salts, form the so-called "brain sand" so frequently met with in the choroid plexus and in the lining of the cerebral ventricles. MM. Cornil and Ranvier have styled this tumour "sarcome angiolithique," from the close connexion found by them to exist between the sandy particles and the small blood-vessels; but little as this growth is known at all, it is perhaps more familiar by Virchow's original appellation than by the more recent French name.

Psammoma may occur as mainly a cystic formation, affecting the choroid plexus, and causing cerebral symptoms only when attaining a large size, or it may assume rather the appearance of a papillary or warty growth, springing from the arachnoid or dura mater, and under these circumstances the flattened, slowly growing projection may give rise to no symptoms during life, and will attract notice only as a curiosity in the eyes of the morbid anatomist. In a specimen of the latter variety kindly given to me some weeks since by my friend Mr. Marcus Beck, the tumour was about the size of a florin, and three times its thickness, and its wart-like papillæ sprang from the inner surface of the outer layers of the dura mater, lifting up its inner layer and projecting through this, thrusting aside the ulcerated thin membrane all round. The raggedlooking papillæ were barely held together by some scanty connective tissue, and evidently contained no small amount of gritty particles, although there were no large grains such as are often met with in the choroid plexus. Examined microscopically, scrapings and teased portions (for the loose construction of the mass rendered thin sections unobtainable) showed that the bulk of the new growth was made up of

aggregated flattened fibre-like cells, having much the appearance of connective tissue elements when seen in groups. Isolated cells, however, bore a closer resemblance to delicate irregular pavement epithelium. Many vessels ramified through the growth, and the peculiar concentric bodies-the corpora amylacea-occupied a conspicuous place in every preparation. These bodies had generally so hard and black an outline as to resemble air-bubbles until more careful focussing brought into view a few irregular highly refracting particles in the centre, and faint concentric rings surrounding these, a bold black outline marking the circumference of the tiny spheres. Outside this strongly marked border was generally a lighter fibrous zone (fig. 19). Some of the bodies

FIG. 19.-From a teased-out bit of a psammoma of the dura mater, showing the concentrically marked bodies and some detached epithelial cells. Magnified 220 times.

were pale and free from calcareous incrustation, but the majority were more or less thoroughly infiltrated. Prolonged and careful examination, however, failed to discover any connexion with the vessels such as has been described as an essential characteristic by MM. Cornil and Ranvier. The concentric structure of the bodies seemed to be brought about by the regular superposition of the delicate flattened