The names goiter, struma, and bronchocele are applied indiscriminately to all tumors of the thyroid gland; there are, however, several distinct varieties among them that are true adenoma, which, therefore, deserves a place here. According to Warren, Wolfler gives the following classification of thyroid tumors: 1. Hypertrophy of the thyroid gland, which is a comparatively rare disease; 2. Fetal adenoma, which is a formation of gland tissue from the remains of fetal structures in the gland; 3. Gelatinous or interacinous adenoma, which consists in an enlargement of the acini by an accumulation of colloid material, and an increase in the interacinous tissue by a growth of round cells. It is this latter form in which cysts are frequently found. The accompanying illustration pictures an extreme ease of cystic goiter shown by Warren. A strange feature of tumors of the thyroid is that pressure-atrophy and flattening of the trachea do not take place in proportion to the size of the tumor. A small tumor of the middle lobe of the gland, not larger that a hen's egg, will do more damage to the trachea than will a large tumor, such as that shown by Senn, after Bruns. When a tumor has attained this size, pressure-symptoms are often relieved by the weight of the tumor making traction away from the trachea. Goiter is endemic in some countries, particularly in Switzerland and Austria, and appears particularly at the age of childhood or of puberty. Some communities in this country using water containing an excess of calcium salt show distinct evidences of endemic goiter. Extirpation of the thyroid gland has in recent years been successfully practiced. Warren has extirpated one lobe of the thyroid after preliminary ligation of the common carotid on the same side. Green practiced rapid removal of the tumor and ligated the bleeding vessels later. Rose tied each vessel before cutting, proceeding slowly. Senn remarks that in 1878 he witnessed one of Rose's operations which lasted for four hours. Although the operatic technic of removal of the thyroid gland for tumor has been greatly perfected by Billroth, Lucke, Julliard, Reverdin, Socin, Kocher, and others, the current opinion at the present day seems to be that complete extirpation of the thyroid gland, except for malignant disease, is unjustifiable. Partial extirpation of the thyroid gland is still practiced; and Wolfler has revived the operation of ligating the thyroid arteries in the treatment of tumors of the thyroid gland.

Fibromata.--One of the commonest seats of fibroma is the skin. Multiple fibromata of the skin sometimes occur in enormous numbers and cover the whole surface of the body; they are often accompanied by pendulous tumors of enormous size. Virchow called such tumors fibroma molluscum. Figure 237 represents a case of multiple fibromata of the skin shown by Octerlony. Pode mentions a somewhat similar case in a man of fifty-six, under the care of Thom. The man was pale and emaciated, with anxious expression, complaining of a tumor which he described as a "wishing-mark." On examination he was found to be covered with a number of small tumors, ranging in size from that of a small orange to that of a pin's head; from the thoracic wall over the lower true ribs of the right side was situated a large pendulous tumor, which hung down as far as the upper third of the thigh. He said that it had always been as long as this, but had lately become thicker, and two months previously the skin over the lower part of the tumor had ulcerated. This large tumor was successfully removed; it consisted of fibrous tissue, with large veins running in its substance. The excised mass weighed 51 pounds. The patient made an early recovery.

Keloids are fibromata of the true skin, which may develop spontaneously or in a scar. Although the distinction of true and false keloid has been made, it is generally discarded. According to Hebra a true typical keloid is found once in every 2000 cases of skin-disease. It is, however, particularly the false keloid, or keloid arising from cicatrices, with which we have mostly to deal. This tumor may arise from a scar in any portion of the body, and at any age. There seems to be a disposition in certain families and individuals to keloid-formations, and among negroes keloids are quite common, and often of remarkable size and conformation. The form of injury causing the cicatrix is no factor in the production of keloid, the sting of an insect, the prick of a needle, and even the wearing of ear-rings having been frequent causes of keloid-formations among the negro race. Collins describes a negress of ninety, born of African parents, who exhibited multiple keloids produced by diverse injuries. At fourteen she was burned over her breasts by running against a shovelful of hot coals, and several months later small tumors appeared, which never suppurated. When a young girl a tumor was removed from the front of her neck by operation, and cicatricial tumors then spread like a band encircling one-half her neck. There were keloids over her scapulae, which followed the application of blisters. On her back, over, and following the direction of the ribs, were growths attributed to the wounds caused by a flogging. This case was quite remarkable for the predisposition shown to keloid at an early age, and the variety of factors in causation.

About 1867 Duhring had under his observation at the Philadelphia Hospital a negro whose neck was encircled by enormous keloids, which, although black, otherwise resembled tomatoes. A photograph of this remarkable case was published in Philadelphia in 1870.

A lipoma is a tumor consisting of adipose tissue. When there is much fibrous tissue in the tumor it is much firmer, and is known as a fibro-lipoma. Brander describes a young native of Manchuria, North China, from whom he removed a fibro-lipoma weighing 50 pounds. The growth had progressively enlarged for eleven years, and at the time of extirpation hung as an enormous mass from beneath the left scapula. In operating the tumor had to be swung on a beam. The hemorrhage was slight and the patient was discharged in five days.

The true lipoma must be distinguished from diffuse accumulations of fat in different parts of the body in the same way that fibroma is distinguished from elephantiasis. Circumscribed lipoma appears as a lobulated soft tumor, more or less movable, lying beneath the skin. It sometimes reaches enormous size and assumes the shape of a pendulous tumor.

Diffuse lipoma, occurring in the neck, often gives the patient a grotesque and peculiar appearance. It is generally found in men addicted to the use of alcohol, and occurs between thirty-five and forty-five years of age; in no case has general obesity been described. In one of Madelung's cases a large lobe extended downward over the clavicle. The growth has been found between the larynx and the pharynx. Black reports a remarkable case of fatty tumor in a child one year and five months old which filled the whole abdominal cavity, weighing nine pounds and two ounces. Chipault mentions a case of lipoma of the parietal region, observed by Rotter. This monstrous growth was three feet three inches long, descending to the knees. It had its origin in the left parietal region, and was covered by the skin of the whole left side of the face and forehead. The left ear was plainly visible in the upper third of the growth.

Chondroma, or enchondroma, is a cartilaginous tumor occurring principally where cartilage is normally found, but sometimes in regions containing no cartilage. Enchondroma may be composed of osteoid tissue, such as is found in the ossifying callous between the bone and the periosteum, and, according to Virchow, then takes the name of osteochondroma. Virchow has divided chondromata into two forms--those which he calls ecchondromata, which grow from cartilage, and those that grow independently from cartilage, or the enchondromata, which latter are in the great majority. Enchondroma is often found on the long bones, and very frequently upon the bones of the hands or on the metatarsal bones.

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