FIG. 54.
From photograph of a case of Professor Osler's, showing secondary myeloid sarcoma of mediastinum—appearing six months after removal of myeloid sarcoma of radius. The tumor figured in the plate occupied the front of the thorax lying beneath the sternum and the cartilages and ribs of the left side, pushing back and completely covering the pericardium. It was loosely adherent to the ribs and sternum, and appeared to grow from the pulmonary pleura, to which it was attached in a large part of its extent, and only had penetrated the lung at one spot on the anterior border of upper lobe. Right lung contained secondary masses, chiefly in the pleura.

Lympho-sarcoma of the Mediastinum.—Lympho-sarcoma, lymphoma, or lymphadenoma is the form of malignant process which probably includes the majority of cases of primary mediastinal growth. It is sometimes, however, a part of a more general disease, affecting more or less the whole glandular system.

Murchison15 classified the first case of this disease involving the intestines, liver, mesentery, and heart. The same observer the following year described a case in which the glands of the neck, mediastinum, axillæ, and spleen were involved. Wunderlich has recorded a case of malignant mediastinal disease which commenced in the glands of the neck; but the cervical glands may be enormously enlarged without implication of the bronchial.

15 Path. Soc. Trans., London, vols. xx. and xxi., together with a summary of the literature of the subject.

The general disease dates back to the time of Hodgkin, Bright, and Wilkes, and was then known as anæmia lymphatica. It has been specifically described by Virchow,16 Cornil, and Ranvier as independent of leukæmia, and was designated lymphadénie. It was noticed by Trousseau under the title of adénie, and Ogle and numerous clinical observers since have also recorded cases.

16 Die Krankhaften Geschwülste, Band ii. p. 376.

As a mediastinal growth the characteristics of lympho-sarcoma can be made more vivid by the reproduction of one of the first cases recorded of this disease. On removing the sternum and cartilages they were found adherent to a mass occupying the anterior mediastinum. The morbid growth reached backward to the trachea, surrounding it with a thickness posteriorly of a quarter of an inch; it extended downward to the bifurcation of the trachea, and, involving the superior prolongation of the pericardium, invaded and greatly thickened the parietal part of that membrane, covering the heart at its upper half. The diseased structure reached upward to the root of the neck, involving the anterior mediastinal glands, and surrounded the trachea by a thin layer as high as the thyroid cartilage. Some of the glands on each side of the neck were affected as high as the angle of the jaw. Laterally, the morbid growth extended on each side to the line of junction of the cartilages with their ribs, displacing the anterior margin of the lung. The pulmonary pleura was involved and thickened at the line of contact, and the right lung at the upper part of its anterior margin was invaded from the pleura by white, fibrous-looking branched bands. At the lower part of the anterior lobe the lung was also invaded from the pericardium. Some of the glands at the root of the lung were involved by extension, but they were not generally affected, nor was the lung invaded except to the limited extent above mentioned. The heart and pericardium were free from disease.17

17 Powell, Path. Trans., vol. xxi., London.

The malignant growths of the mediastinal region implicate the surrounding structures so rapidly that it is, as a rule, quite impossible to determine, even after death, the starting-point of the disease; and while lymphadenoma can originate in the same tissues as the other forms of sarcoma already alluded to, yet it in most cases probably originates in the lymphatics of the anterior or posterior mediastinum.

In reference to the location of this form of morbid growth, we find, on consulting a series of cases reported by Fenwick, Eve, Payne, Peacock, Powell, Murchison, Bennett, Dickinson, that the region for principal development seems to be the anterior mediastinal space, although in several instances the posterior mediastinal region was also involved.