TUMORS do not admit of a simple definition, but, in the words of sir James Paget, who has specially investigated this department of surgical pathology, they all belong to the class of overgrowths or hypertrophies, and their most constant distinctive charac ters are: (1) that they are deviations both in respect to size and shape from the normal type of the body in which they are found; (2) that they have an apparently inherent power and method of growth; and (3) that their development and growth are independ ent of those of the rest of the body, continuing with no evident purpose when the rest of the body is only being maintained in its normal type.
Tumors are usually divided into two chief groups, known as innocent or benign, and malignant tumors. The characters of the latter are sufficiently discussed in the a'ticle CANCER, and we shall therefore restrict our remarks to innocent tumors. These may be divided into cystic tumors, or cysts, and solid tumors; while the latter are subdividet, into the discontinuous and the continuous; the discontinuous being those which are completely invested with a layer of tissue, which at once isolates them and connects them with the surrounding parts. while4he continuous ones appear as growths, not in, but of the sur rounding parts, and appear as outgrorths, as, for example, many polypi, and pendulous or sessile tumors. In accordance with these ideas, sir J. Paget classifies innocent tumors as follows: I. CYSTIC TH3IORS: CYSTS; which may be (A) simple or barren or (B) compound or proliferous. (A) simple cystic tumors include the varieties known as (a) se rous, constituting what arc termed hydromata, (b) synovial, (c) mucous, (d) sanguineous, (e) oily, (f) colloid, (g) seminal. (B) Compound or proliferous tumors, including (a) com plex cysts, (b) cysts with glandular or oilier vascular growths, (c) cutaneous cysts, (d) dentigwous cysts. II. SOLID TUMORS and OUTGROWTHS, including (a) fatty or adipose, (b) fibre-cellular, areolar, etc., (c) fibrous, fibro-muscular, (d) cartilaginous, (e) myeloid or marrow-like, (f) osseous, (g) glandular, and (It) vascular.
Of these various species we shall only notice a few of the most important. Cutaneous cysts may be congenital or acquired. They may be found under the skin of any part, but sir J. Paget regards them as probably a hundred times more common in the scalp than in any other part. Their rate of growth is uncertain. When they grow rapidly they are apt to ulcerate, and hence are derived most of the so-called "horns" of the scalp and face.
Cutaneous cysts are usually formed either by the morbid growth of natural ducts or follicles, or by the enormous growth of elementary structures, which increase from the form of cells and nuclei, and become closed sacs with organized walls capable of pro ducing other growths. A hair follicle or a sebaceous gland of its duct become ob
structed, is thus often the origin of a cyst. Cutaneous cysts may be treated in various ways. Those in which the skin over their chief prominence is marked with a small dark point, through which a fine probe may be passed into the cavity, may be gradu ally emptied by dilating their openings, and pressing out their contents; or they may be extirpated by caustic or the knife.
Patty tumors are the most frequent of all innocent tumors, and are often described under the name of lipoma and steatoma. They do not differ materially in structure from the ordinary fat of the adjacent parts, and seldom cause much annoyance, except from their unseemly appearance. No good cause can be assigned for their formation, but they may sometimes be traced to a blow or friction, as of a strap. The age at which they most commonly show themselves is at about forty. They may occasionally be absorbed by the prolonged internal use of liquor potassm; but this treatment is almost certain to disturb the general health, and, as a general rule, excision is the proper treatment. Fthro-cellular tumors are remarkable fur the rapidity of their growth (three or four pounds in the year, and, in one case rec,..rded by sir j. Paget, a pound a month), and the weight which they may attain (sometimes forty pounds or more). The most common seat of these tumors are the uterus, the scrotum, the bones, the subcutaneous tissue, the lobules of the ear, etc. Polypi of the uterus, nose, etc., belong to this class. Except in the case of polypi, excision is the only available remedy; and iu some parts of the body this is of course impossible.
We will conclude with a reference to a remarkable class of cases which often sadly puzzle the inexperienced surgeon. They are known as phantom tumors, and are apparently due to contraction of the muscles. "The abdominal muscles of hysterical women are most often thus affected; sometimes with intentional fraud. The imitation of a tumor may be so close as to requiie great tact for its detection, but chloroform, by relaxing the muscles, dissipates the swelling. Occasionally these apparent tumors move."—Paget on "Tumors," in Holmes's System of Surgery, vol. i., an article contain ing an excellent abstract of the most recent knowledge on the general subject of tumors.