rbit.

(Sir Montagu Cotterill's case)]

The margin, while in parts irregular, is typically represented by a
well-defined "rolled" border which consists of the peripheral portion of
the cancer that has not broken down. The central ulcer may temporarily
heal. There is itching but little pain, and the condition progresses
extremely slowly; rodent cancers which have existed for many years are
frequently met with. The disease attacks and destroys every structure
with which it comes in contact, such as the eyelids, the walls of the
nasal cavities, and the bones of the face; hence it may produce the most
hideous deformities (Fig. 103). The patient may succumb to haemorrhage or
to infective complications such as erysipelas or meningitis.

Secondary growths in the lymph glands, while not unknown, are extremely
rare. We have only seen them once--in a case of rodent cancer in the
groin.

_Diagnosis._--Lupus is the disease most often mistaken for rodent
cancer. Lupus usually begins earlier in life, it presents apple-jelly
nodules, and lacks the rounded, elevated border. Syphilitic lesions
progress more rapidly, and also lack the characteristic margin. The
differentiation from squamous epithelioma is of considerable importance,
as the latter affection spreads more rapidly, involves the lymph glands
early, and is much more dangerous to life.

_Treatment._--In rodent cancers of limited size--say less than one inch
in diameter--free excision is the most rapid and certain method of
treatment. The alternative is the application of radium or of the
Rontgen rays, which, although requiring many exposures, results in cure
with the minimum of disfigurement. If the cancer already covers an
extensive area, or has invaded the cavity of the orbit or nose, radium
or X-rays yield the best results. The effect is soon shown by the
ingrowth of healthy epithelium from the surrounding skin, and at the
same time the discharge is lessened. Good results are also reported from
the application of carbon dioxide snow, especially when this follows
upon a course of X-ray treatment.

#Paget's disease# of the nipple is an epithelioma occurring in women
over forty years of age: a similar form of epithelioma is sometimes met
with at the umbilicus or on the genitals.

#Melanotic Cancer.#--Under this head are included all new growths which
contain an excess of melanin pigment. Many of these were formerly
described as melanotic sarcoma. They nearly always orig