The skin lesions which precede the formation of paraffin cancer resemble those seen in chimney-sweeper’s cancer. The skin becomes dry, thickened, parchment-like, while the openings of the sebaceous glands become obstructed by the tar or other material, producing acne-like lesions. Warty outgrowths then occur, and these become the seat of malignant ulceration. In chimney-sweeper’s cancer the scrotum is usually first affected in a chronic dermatitis, to which warty outgrowths succeed, these enlarging and growing downward as ulceration takes place.
About the external genitalia epithelioma is not uncommon, particularly in and about the prepuce. Such a degree of phimosis as leads to retention of smegma is certainly a predisposing cause, not only in man but in the lower animals. Epithelioma of the vulva has been described under the name esthiomène, and requires to be recognized and dealt with promptly if the surgeon should attempt a radical cure. In the vagina and about the cervix uteri it is common, a large proportion of cases of cancer of the uterus being essentially epitheliomas of the cervix.
In and about scars and upon granulating ulcers epithelioma is quite common. One danger to which a chronic ulcer is always exposed is that of epitheliomatous transformation. These growths also attack lupus scars, or even any tissues actively involved in the lupoid process. This is particularly true between the fortieth and sixtieth years of life.
Among the viscera the gall-bladder is probably more often involved in distinct epitheliomatous changes than any other. It presents as a uniform thickening, and causes augmentation in size, so that a distinct tumor projects from beneath the liver. In this location dessemination is rare.
Epithelioma is to be regarded as having an essential malignant tendency. Its treatment demands early removal of diseased parts and complete extirpation of involved lymph nodes. It is only the small and incipient growths which should be attacked by such destructive agencies as cancer pastes or the electrolytic current.
Rodent Ulcers.
—Under the name of rodent ulcers, lupus exedens, noli-me-tangere, etc., writers, mostly English, have described a variety of epithelioma, met especially upon the face, to which a separate classification has usually been assigned. Until recently it has been generally regarded as a local ulceration, distinct from cancer. In some text-books it is described as lupus exedens. It is preceded usually by a nodular condition of the skin, vascular, breaking down into a regular ulceration, but little elevated, the base of the ulcer deeply excavated, with a striking disproportion between ulceration and new-growth. In this particular variety infiltration seems to be continuously in advance of the rodent process, the former being excessive, the latter but slight. This variety of epithelioma rarely produces lymphatic involvement; the discharge is slight, the pain complained of inconsiderable. Occasionally it entirely alters its aspect, and may present features of the conventional epitheliomatous type.
Fig. 91
Fig. 92