In the mucous membrane of the stomach and bowels adenoma usually presents as an ovoid tumor, attaining such size as to give rise to mechanical obstruction either by pressure or by traction. Adenoma of the pyloric region is a repetition in structure of the pyloric glands. In the rectum it presents usually as a polypoid outgrowth, often seen in young children. Such tumors are generally small, and when solitary they often hang by a distinct stalk.
Similar polypoid tumors present in the cervical canal of the uterus, where are also found sessile and racemose tumors, all of which are structural repetitions of the glands met with in the cervix uteri. Adenoma of the uterine cavity is seldom seen; it is also rare in the Fallopian tube, but occasionally presents as a dendritic outgrowth from the mucous membrane distending the tube.
Epithelioma.
—Epithelioma is common, especially where there is transition from one kind of epithelium to another, and, of all other localities, particularly where skin and mucous membrane meet—e. g., the lips, the vulva, and the anus. Epithelioma differs from papilloma in that the former is no longer limited by basement membrane, but passes beyond it into the underlying connective tissue and presents down—rather than up—growth. Characteristic of epithelioma are the so-called cell nests or pearly bodies, where there seems to be a tendency to globular arrangement of cells with such condensation or alteration that they lose their ability to take stains, and appear as a more or less lustrous mass, showing off by contrast among the standard surrounding tissue. On this account they are often called pearly bodies. Recognition of these is tantamount to diagnosis of epithelium. (See [Plate XXIII].)
This form of neoplasm is essentially the same, no matter what its clinical varieties. These comprise a wart-like growth or nodule, which quickly becomes an ulcer with elevated edges, ulceration being due to necrosis of cells farthest from the periphery; or, again, the disease may start as an ulcerated fissure, ulceration and infiltration keeping pace, in which case there is a sharply defined ulcer with undermined edges. A third variety, often seen upon the lips, comprises a projecting mass, with more or less horny surface. In nearly all of these, however, the characteristic cell nests with their onion-like arrangements of cells will be found.
Epithelioma, especially when exposed to the air or to surface irritation, quickly ulcerates and tends to involve all the surrounding tissues, while occasionally the distinctive cells proliferate so rapidly as to give the ulcer more or less of a bursal or a cauliflower-like arrangement. From such a surface there is a constant discharge of foul-smelling detritus or of sloughs. Even bone cannot resist its progressive invasion and slowly disintegrates before the advancing mass. Cartilage is resistant, and usually preserves its integrity. In other words, the tendency of epithelioma is toward constant encroachment and infiltration, and toward a fatal termination from hemorrhage by ulceration, from septic infection, exhaustion, or other accidents. The wart-like forms run the slowest course of all, but even here the malignant tendency is most evident.
Lymph-node Infection.
—A striking characteristic of epitheliomas is the invasion of the adjoining lymph nodes, which attain a size disproportionate and bearing no necessary relation to that of the primary growth. This constitutes one of the most serious complications of the condition. This lymphatic invasion partakes of the malignant character of the disease, and from every focus of this character infiltration and destruction proceed. Infected nodes also show an early tendency to central degeneration and to spurious cyst formation. When the overlying skin becomes involved we have extensive sloughing and the conversion into large malignant ulcers. Dissemination to a distance (i. e., metastasis) is rare in epithelioma—much more so than in carcinoma. (See [Plate XXV, Fig. 2].)
About the mouth epithelioma is not common before the thirty-fifth year, though I have seen it on the lip of a twenty-year-old woman. It is vastly more common in men than in women, and more frequent on the lower than the upper lip. In the tongue it seldom occurs before the fortieth year. It seems to be more common both on the lip and tongue in men with bad teeth and in confirmed smokers, thus giving rise to the view often held that it is purely a matter of irritation. It may, however, be due to contact infection should it be regarded as of parasitic origin. In one-fifth of the cases of epithelioma of the tongue there are preceding lesions, usually described as leukoplakia or ichthyosis of the tongue—conditions characterized by epithelial reduplication and the formation of dense plaques or scales. These lesions are usually regarded as precancerous conditions. (See [Plate XXVI].)
PLATE XXIV