Adenoma.—An adenoma imitates, but does not fulfill, the function of the se creting gland in which it is found. The 1 situations where adenomata are found are given in the classification of tumors.
Adenoma is the nearest approach to a malignant tumor which is consistent with a non-parasitic theory. It requires only the added impetus of a parasite to con vert an innocent enlargement into an exceedingly malignant growth. Roswell Park (Amer. Jour. Med. Sci., May, '93).
Carcinoma. — Cancers arise from a malignant proliferation of glandular tis sue, the cause of which is at present un known. They at first resemble adeno mata in their growth, but gradually be come less and less like the glands from which they originate, until irregular clumps of epithelial cells have broken through their lining membrane and are to be found collected in the acini and ducts.
In explaining to students the differ ences between a normal gland, adenoma, and cancers the following simile is often employed by pathologists: A gland may be likened to a dwelling-house complete in every detail, the acini being the room, the ducts the passage-way, the connective tissue the frame-work, and the epithe lium the plaster upon the walls. Follow ing this simile, an adenoma may be re garded as an architecturally atypical house in which there has been a purpose less addition of rooms or halls, but in which each addition still shows, more or less clearly, the normal frame-work and plaster. In cancer the arrangement is as if the house had collapsed and the plaster (epithelial cells) had broken through the walls (connective tissue) into the rooms (acini) and halls (ducts), and then all of the constituents had grown in a con glomerate sort of a fashion, involving first the neighboring houses (tissues) and finally affecting those houses (other organs) at a distance (metastasis).
Oiiphoreetomy or an abdominal section at times may cause a malignant tumor to become inactive or even to decrease in size. Again, the prompt diagnosis of cancer of the body of the uterus is most important, as an early hysterectomy is attended with the most beneficial results, while the operation is almost hopeless after the disease has invaded the cervix.
On the other hand, Gould (Trans. Clin. Soc., vol. xxx) reports a case of spon taneous disappearance of secondary can cerous growths in the female breast.
Snow (Lancet, Jan. 9, '97) believes that infection of the marrow of the bones occurs in nearly all cases of cancer of the breast, the humerus being the first bone affected, as manifested, after the disease has existed eighteen months, by tender ness on pressure, and possibly slight thickening may be made out. The result is a firm, white marrow.
Babes and Stoicescu (Ann. de l'Inst. de Path. et de Bad. de Bricarest, vol. vi, p. 405) believe that it is possible to diag nose the presence of cancer of the inter nal organs by a microscopical study of the small cutaneous masses which times appear by metastasis beneath the skin of the patients so affected.
Keen, in his lectures, alludes to a case in which skin-grafting from the thigh was practiced upon the breast where a carcinoma had just been. A cancerous nodule developed at the place from which the healthy skin was taken, no doubt from direct infection from the breast.
After three years' work in the New York State Pathological Laboratory of the University of Buffalo, the writer has found what he regards as the cause of cancer. In all the cases of cancer so far examined it Has been noted that by fresh methods the organisms can always he found. These bodies resemble fat in the fresh state. It was only when the ether test and the osmic-acid test had been applied that it was discovered that they were not particles of fat. He next discovered that he could crack their edges with the cover-glass. They were then injected into the abdominal cavities of animals. Most of the animals developed peritonitis, and large quanti ties of these bodies could be obtained from the peritoneal fluid. The round form may be observed to develop under the cover-glass. They can be found in every cancer if properly sought for, and can be injected into animals and be re covered. They also change their form.