CHAPTER III.

OF TUMORS.

In giving a brief description of tumors, the following classification has been adopted from Gross, as presenting the most practical and convenient arrangement of the subject:

I. _Benign or Non-Malignant Tumors._

1. Cystic Tumors.

_a._ Simple Cysts; including Serous, Mucous, Synovial, Colloid, Sanguineous, Salivary, Milk, Oil, Seminal, and Dermoid Cysts.

_b._ Compound or Proliferous Cysts.

2. Hydatid Tumors.

3. Myxomatous „

4. Lipomatous „

5. Fibrous „

6. Cartilaginous „

7. Osseous „

8. Papillary „

9. Polypoid Tumors.

10. Myomatous „

11. Vascular „

12. Neuromatous „

13. Adenoid „

14. Lymphatic „

II. _Malignant Tumors._

1. Sarcomatous Tumors.

_a._ The Round Celled.

_b._ The Spindle Celled.

_c._ The Giant Celled.

2. Carcinomatous Tumors.

_a._ Scirrhus Tumors.

_b._ Encephaloid „

_c._ Melanotic „

_d._ Colloid Tumors.

_e._ Epithelial „

I. Benign or Non-Malignant Tumors.

1. =Cystic Tumors.= These are of very frequent occurrence, and may acquire an extraordinary size. Their structure may be simple or very complex, and we may accordingly divide them into simple or barren, and compound or proliferous cysts. They may be new formations or, as in most cases, merely hypertrophies. They occur in nearly every organ and tissue of the body, but are most frequently met with in the skin and mucous membranes, the glandular organs, and in the subcutaneous cellular tissue.

=A.= _Simple Cysts_ generally consist of a thin sac or cyst filled with contents, varying according to the structure and function of the affected part. The cyst itself may be solitary or multiple, generally composed of a single layer, its external surface being rough and adherent to the surrounding tissues, while the internal surface is shining or glossy, and in immediate but loose contact with the contents of the tumor.

According to the nature of their contents, we may find the following varieties of simple cysts:

_Serous Cysts._ Their contents are generally of a thin, watery character, slightly saline in taste, and consisting largely of albuminous material. The walls are thin, and at first translucent; as they grow older they become thicker and denser.

_Mucous Cysts_ generally contain a thick, ropy, glutinous material, intermixed with epithelial matter. Sometimes the contents are thin and clear; occasionally they resemble the fluid contained in a synovial bursa. Such tumors occur chiefly in connection with the mucous membranes, are generally spherical or pyriform in shape, and may attain the size of a fœtal head.

_Synovial Cysts_ are generally small in size, rounded, globular, or hemi-spherical in shape, with contents of a serous, mucus, glutinous, colloid, or of a jelly-like consistence, and of a whitish, opaque appearance. They occur generally in the synovial sheaths of the tendons of the wrist, and on the front of the patella. The most characteristic types of synovial cysts are those known as ganglions and bursæ.

_Colloid Cysts_ are rarely met with as independent structures; they usually occur as accidental constituents of various kinds of morbid growths. Their contents vary in consistence between mucus and the thickest jelly, “their color being generally whitish or pearl-like, not unfrequently blended with shades of pink, yellowish-brown, or olive-green.”

_Sanguineous Cysts_, or hæmatomata, may be entirely new formations, or may occur in a normal cavity. Their contents may consist either of pure blood or of blood mingled with serum and other substances. “The cyst wall is usually very thin and smooth; but in some cases the inner surface has a peculiar fasciculated appearance, not unlike that of the right auricle of the heart.” The cyst is commonly small, and of a rounded or hemi-spherical shape.

_Salivary Cysts_ are most frequent in connection with the sublingual gland, constituting the so-called ranula. The contents of these cysts are thick and ropy, like the white of egg, and consist essentially of saliva, mixed with mucus and epithelial matter.

_Milk Cysts_ are liable to be formed in the mammary gland during lactation. Their size varies. Their contents may be pure milk and perfectly liquid, or mixed with caseous and epithelial substances.

_Oil Cysts_ are of rare occurrence, and usually of quite small size. They occur most frequently in the skin or in some glandular organ, especially the breast. Their contents are generally fatty matter, with epithelial and other substances.

_Seminal Cysts_ are never of independent growth. They contain a fluid, mostly serum, with the characteristic spermatozoa held in suspension, and only to be detected by the microscope. The only true tumors of this kind are hydroceles of the spermatic cord.

_Dermoid Cysts_ are usually congenital, and, in the majority of cases, contain the debris of a blighted ovum, such as hairs, teeth and bone. Sebaceous tumors are a variety of dermoid cysts, and contain sebaceous matter, combined with epithelium and even hair, oil or fat.

=B.= _Compound or Proliferous Cysts_ are “characterized by the existence of subordinate cysts, occupied by different organized substances, and giving rise to that peculiar arrangement known as multilocular or polycystic, generally so conspicuous in this class of tumors.” When a number of cysts are crowded together, their walls are frequently absorbed, and irregular cavities, varying in size and shape, are thus formed. Their contents are of the most diversified character. The cyst wall is thin at first, but becomes thicker and firmer in a later stage.

Proliferous cysts sometimes take on a malignant character, of the encephaloid or epithelial type, years after their origin. They occur most frequently in the ovary, the mammæ, and the thyroid gland. In the first situation, they not unfrequently attain an enormous size.

2. =Hydatid Tumors.= These tumors occur most frequently in the liver, ovary and uterus. They consist of a distinct sac, enclosing an entozoon, parasite or vesicular worm, “varying in volume between a mustard-seed and a small orange. The entozoon is of a globular figure, of a whitish, semi-opaque appearance, and composed of a vesicle or bladder, filled with serous fluid, and surrounded by a cellulo-fibrous capsule.” Generally a number of them are found in a common cyst. “The contents of the animal are of a clear, limpid character, remarkably saline to the taste, but destitute of odor and coagulability. Between the cyst and the parasite there is commonly a soft, pulpy, dirty-looking substance, the precise nature of which is undetermined. Large hydatids sometimes contain several smaller ones, one within the other.”

“The inner surface of the parasite is studded with numerous little bodies, resembling diminutive fish-spawn, hardly as large as a grain of sand, of a spherical shape and of a grayish color, each consisting of a delicate cyst, filled with echinococci.”

“Each echinococcus consists of a body and a head, the latter being encircled by a row of teeth, naturally concealed in a narrow cleft, but capable of projecting itself. The body, composed of solid, granular matter, has a curiously speckled appearance, due to the presence of numerous ovoid spots immediately beneath its outer coat. The teeth, or hooklets, are spinous, sharp, and perfectly characteristic.”

3. =Myxomatous Tumors.= The _Myxomata_ or mucous tumor, consists of mucous tissue, a translucent and succulent connective tissue, the intercellular substance of which yields mucin. Their characteristic features are elasticity and softness; the older growths, however, are harder than the more recent ones. They are of a pale, greyish or reddish-white color. They consist of a basement structure, the proper stroma of the tumor, and an intercellular substance, pervaded by distinctly visible blood-vessels. On being cut, they yield, on pressure, the tenacious, mucilaginous, intercellular liquid, in which may be seen the cellular elements of the growth. The majority of the cells, under the microscope, are found to be angular and stellate, with long, anastomosing prolongations and trabeculæ. Others are isolated and fusiform, oval or spherical in shape. They usually possess one, in some cases two distinct nuclei. Fat cells, fibrous tissue, both white and elastic, and cartilage in varying proportions, are often met with in the morbid mass.

They occur chiefly in the subcutaneous and intermuscular cellular tissues, in the mucous cavities, in the hilus of the kidney, and in the nerves and bones. When situated in superficial parts they may become pedunculated. In the submucous tissue of the nose they constitute the gelatinoid polypus. Other perfect types of mucous tumors are seen in the polypi of the ear and the uterus.

4. =Lipomatous Tumors.= The _Lipomata_ or fatty tumors are very common, and may occur in any part of the body. There may be but one, or they may appear in very large numbers in different parts of the body. They sometimes attain an enormous size. They are lobulated, and are usually surrounded by a fibrous capsule, which separates them from the adjacent structures. Their consistence varies according to the amount of fibrous tissue that enters into their formation. They frequently become pedunculated, or assume a pyriform shape, no doubt by reason of their weight, by which they are gradually dragged out of their original shape, as well as position. They resemble in structure, as also in appearance on section, adipose tissue. They consist of more or less round or polygonal cells, distended with fluid fat, and united into masses or lobules of various sizes by connective tissue, which also forms a sort of capsule around the tumor, and connects it more or less firmly to the parts around.

Inflammation, suppuration, ulceration, and even gangrene may occur in these growths. They may also undergo at certain points, fibrous, cartilaginous or osseous degeneration. Cysts filled with various kinds of substances may also occasionally occur within them.

5. =Fibrous Tumors.= The _Fibromata_ appear in very different parts of the body, commonly in those which normally contain much fibrous tissue. Several may exist in the same organ, more particularly in the uterus, rarely do they coexist in separate organs. Their form is mostly spherical, generally with a smooth, even surface, although not unfrequently it is lobulated, or marked by numerous elevations and depressions. They feel heavy and incompressible. Near a free surface they are prone to become pedunculated. They may attain a very great size. Their vascularity is in proportion to the density of their structure, some having but few vessels, while others are highly vascular. A distinct capsule is but seldom met with, although the tissues around the tumors will usually be found a great deal condensed and thickened.

They consist essentially of fibres, resembling those of areolar tissue. “Sometimes the fibres are tolerably distinct and separate, more often so interlaced and blended together, or so imperfectly evolved that they cannot be made out as such. Yellow elastic fibres are not unfrequently mingled with the white.”

Growths of this kind are not, in general, liable to any great degree of change. Inflammation, with injection and softening of the part may take place. Cretification may occur, by which either the whole tumor may be converted into a calcareous mass, or only the outer stratum surrounding the rest as a kind of shell.

6. =Cartilaginous Tumors.= The _Enchondromata_, histologically resemble cartilage, and like it consist of cells and an intercellular substance, presenting all the variations observed in the normal tissue. The intercellular substance may be hyaline, fibrous, or mucoid, or as most frequently is the case, all combined. The cells are round, oval, spindle-shaped or stellate, and may be very numerous, or few in proportion to the matrix. They enclose one or more nuclei, and slightly granular contents; sometimes a cell-wall cannot be distinguished.

In addition to the intercellular tissue, the growth is usually divided into several lobes by bands of fibrous tissue. The fibrous tissue in most cases, forms a capsule around the tumor, and separates it from the surrounding structures.

The enchondroma is met with most frequently in early life, and occurs chiefly in connection with the osseous system, principally the metacarpal bones, and phalanges of the fingers, where it may grow either from the periosteum or from the medulla. It is met with also in the parotid and submaxillary glands, in the testicle, mammæ and ovary, and occasionally in the subcutaneous and intermuscular cellular tissue.

They may attain an enormous size. “To the hand, it imparts the sensation of unusual firmness and solidity; it is destitute of elasticity, is generally distinctly circumscribed, and is nearly always strongly adherent to the tissues from which it springs.”

Calcification and ossification of these tumors may occur. In rare cases, the skin covering the tumor ulcerates, and a fungating mass protrudes.

Although in general an innocent growth, the enchondroma in some instances, assumes a malignant form, and recurs after extirpation.

7. =Osseous Tumors.= The _Osteomata_ are tumors consisting of osseous tissue, met with chiefly as outgrowths of the skeleton, especially of the external and internal surfaces of the skull, and of the thigh bone.

There are three classes, the soft, spongy or cancellous, the compact, and the eburnated osteoma.

The _spongy_, which is the most common, consists of cancellous osseous tissue. The medullary spaces may contain embryonic tissue, a fibrillated tissue, or fat. “In its earlier stages, it is often invested by a layer of cartilage, of a greenish, whitish, slightly bluish, or pearly aspect, and of a hyaline character. Sometimes it is enclosed by a thin, fibrous, or fibro-cellular capsule, a form of synovial bursa, lubricated by serous or sero-oleaginous fluid.”

The _compact osteoma_ is generally more or less rounded, with a nodulated surface, and a broad base. It is of a firm, bony consistence, and resembles, as nearly as possible in structure, the compact tissue of the long bones, differing only in the arrangement of the Haversian canals and canaliculi, which is less regular than in normal bone.

The _eburnated osteoma_ consists of dense osseous tissue. The lamellæ are arranged concentrically and parallel to the surface of the tumor. Blood-vessels and cancellous tissue are both absent. The tumor is of small size, rounded, globular or hemi-spherical in shape, and generally smooth, or slightly nodulated.

8. =Papillary Tumors.= The _Papillomata_ resemble in structure ordinary papillæ, and like these grow from cutaneous and mucous surfaces.

They consist of a basis of connective tissue, supporting blood-vessels, which terminate in a capillary net-work, or in a single capillary loop, the whole being enveloped in a covering of epithelium, varying in character according to the surface from which the new formation springs. These growths are sometimes very vascular.

On the skin we may have these growths as _warts_ and _horny_ growths. These are commonly firm, with a dense epithelial covering, and are less liable to ulceration and hæmorrhage, than those growing on other parts. But we have, in the _condylomata_ and _venereal warts_, occurring around the anus and upon the external male and female genital organs, instances of larger and more vascular forms on cutaneous surfaces.

On the mucous membranes, the papillomata are softer and more vascular, and have a less dense epithelial covering. Many of them constitute so-called mucous polypi. They are met with on the tongue, in the larynx and nose, in the gastro-intestinal mucous membrane, on the cervix uteri, and in the bladder.

9. =Polypoid Tumors.= These growths occur exclusively in the mucous cavities of the body, and may attain a large size.

They occur most frequently in the nose and the uterus, but are also met with in the ear, maxillary sinus, vagina and rectum, while their presence in the larynx and throat is exceedingly rare.

They are usually solitary, varying in size and shape according to the locality which they occupy.

Four varieties are met with, differing essentially in their structure.

The _gelatinoid polypus_, the most common of all, occurs almost exclusively in the nose. It is of a jelly-like appearance, irregularly pyriform in shape, with a narrow pedicle, sometimes nearly an inch in length. It is nourished by a few straggling vessels, which are often of considerable length and thickness.

The structure of the _fibrous polypus_ is exceedingly dense and composed of fibres, interlacing with each other in all directions. It is tough, hard and incompressible; of a reddish, purple or livid hue. It is nearly always solitary, may attain a large size, and is usually attached firmly by a broad base, and not by a pedicle. The uterus, nose and maxillary sinus, are its most common sites.

The _granular polypus_, is of rare occurrence. It is met with chiefly in the uterus and in the ear. It is generally small, of a pale, greyish, or whitish color, soft and fragile in consistence, and globular, conical, or ovoidal in shape. Its structure is granular, homogeneous and inelastic.

The _vascular polypus_, attached usually by a narrow base, is of a florid color, of a soft consistence, and not very large in size. On section we find numerous vessels interspersed throughout a fibro-cellular tissue.

Carcinomatous disease is more liable to supervene in the case of the fibrous growths, than in the other of these formations.

10. =Myomatous Tumors.= The _Myomata_ are tumors consisting of muscular tissue, either of the striated, or nonstriated variety. The former are exceedingly rare and generally congenital, the latter are quite frequent and are never congenital; but occur principally in elderly subjects.

They are met with most frequently in the uterus, where they sometimes attain an immense size. They form either distinctly circumscribed tumors of a globular, conical, or pyriform shape, or ill-defined masses in the uterine walls. When projecting into the cavity of the uterus, or into the abdominal cavity, they assume the shape of polypi, with a narrow pedicle.

Myomata may also occur in the prostate gland, in the œsophagus, stomach and intestines.

“In structure they consist of elongated spindle-shaped cells, more or less isolated, or grouped into fasciculi of various sizes, with a varying amount of connective tissue.”

Maceration with dilute nitric acid, is often necessary in order to isolate and display the muscular elements.

11. =Vascular Tumors.= The _Angiomata_ are tumors consisting of blood-vessels, held together by a small amount of connective tissue. They include the various forms of nævi, the erectile tumors, and aneurism by anastomosis.

They are generally met with as congenital affections. Their ordinary sites are the skin and mucous membranes, especially about the head, face and tongue.

They are soft and spongy, easily compressible, and very elastic, varying in color according to the nature of their contents, whether venous or arterial, or both combined.

12. =Neuromatous Tumors.= True _Neuromata_ are tumors consisting almost entirely of nerve tissue. The term has also been applied to growths of other kinds, found in connection with nerves; these are false or spurious neuromata. True neuromata are of very rare occurrence. They consist mainly of a new growth of nerve fibres. “They resemble in structure the cerebro-spinal nerves, consisting of tubular fibres, with a varying quantity of intertubular connective tissue, and in some cases a few gray, gelatinous fibres.” They usually exist as small, single nodules, solid to the touch, firm, inelastic, and developed within the neurilemma of the affected nerve.

The most frequent seat of these growths is the extremities of divided nerves, where they sometimes occur after amputation. They may also exist in the course of the nerves, in any situation, singly, or in great numbers.

13. =Adenoid Tumors.= The _Adenomata_ are new formations of gland tissue, resembling in structure the racemose, or tubular glands. “They consist of numerous small saccules or tubes filled with squamous or cylindrical epithelial cells. These are grouped together, being merely separated by a small, though varying amount of connective tissue, in which are contained the blood-vessels.” They are essentially local hyperplasias. The new growth may remain in intimate relation with the adjacent gland, or it may gradually become separated from it by the formation of a fibrous capsule.

The adenoma is usually a solitary tumor, of a firm, dense, inelastic consistence, of a whitish, grayish, or pale straw color, seldom larger than a hickory nut. On section, the cut surface has a glistening appearance, and in recent cases never yields any fluid on pressure.

It occurs in the mammary, thyroid, prostate, and parotid glands, and in the mucous follicles. In mucous surfaces, it gradually projects above the surface of the membrane, so as to form a polypus, and thus constitute the most common form of mucous polypus.

14. =Lymphatic Tumors.= “The _Lymphomata_ are new formations consisting of lymphatic, or as it is more commonly called, _adenoid_ tissue. This tissue consists essentially of a delicate reticulum, within the meshes of which are contained the so-called lymph corpuscles. The reticulum is made up of very fine fibrils, which form a close net-work, the meshes of which are only sufficiently large to enclose a few, or even a single corpuscle in each. The fibrils usually present a more or less homogeneous appearance, and amongst them there are a few scattered nuclei.”

The lymphatic tumor is most frequently met with in the lymphatic glands of the neck, axilla, groin, and mesentery, and usually consists of several enlarged glands, fused into one common mass of variable size, shape, and consistence. The sectional surface is of a grayish, light pink, or reddish-yellow color, and yields on pressure a whitish, lactescent juice, not unlike that of certain forms of carcinoma, containing cells with one or more nuclei.

II. Malignant Tumors.

1. =Sarcomatous Tumors.= The _Sarcomata_ are tumors consisting of embryonic connective tissue. This differs from the fully developed tissue, in consisting almost entirely of cells, which are also larger and rounder than those of mature tissue. Its intercellular substance, instead of being fibrous, is soft and amorphous or only obscurely fibrillated.

The cells of sarcoma are round, spindle-shaped or stellate, and exist either separately or in conjunction in the same tumor. The latter is most frequently the case; but one form generally predominates, and according to the preponderance of one or the other kind of cell, these tumors can be most conveniently classified as round-celled, spindle-celled, and giant-celled sarcomata.

Round cells are found in all sarcomata, and are often very small, scarcely distinguishable from lymphatic cells, or white blood corpuscles. Others are larger, and contain an indistinct nucleus, with one or more bright nuclei.

The fusiform or spindle-shaped cells are the so-called fibro-plastic cells. They are long, dimly granular, pale bodies, terminating at each end in a fine prolongation. They are slightly granular, and enclose a long, oval nucleus, with or without nucleoli. In size they vary.

The giant or mother cells are the largest of human cells, irregular in shape, though usually more or less spherical. They are finely granular, and contain numerous round or oval nuclei, each with one or more bright nucleoli.

The intercellular substance exists usually in small quantities. “It may be perfectly fluid and homogeneous, or firmer and granular, or, less frequently, more or less fibrillated. Chemically, it yields albumen, gelatin and mucin.”

These growths may occur at any period of life, but are most frequently met with between the twentieth and fortieth year. It is most common in the skin and subcutaneous and intermuscular connective tissues of the extremities. The periosteum and bones, particularly the epiphyses of the long bones and the maxillæ, the female breast, the testicles, and the eye, are also liable to be attacked.

They usually arise as nodules, single or multiple, firm or soft, and often attain an enormous size by their characteristic rapidity of growth. They are liable to fatty degeneration, with the production of cyst-like cavities. Calcification, ossification and mucoid degeneration are also common.

Sarcomata are decidedly malignant, and are characterized by their rapid growth, their great tendency to extend locally, and to recur after removal, and by their power of reproducing themselves in internal organs.

The _Round-celled Sarcoma_, called also from its resemblance in many cases to encephaloid, _medullary_, _encephaloid_ or _soft_ sarcoma, is of a uniform, soft, brain-like consistence, and of a somewhat translucent, greyish, or reddish-white color. The sectional surface, on being scraped, yields a juice rich in cells. It is exceedingly vascular, with the vessels often dilated and varicose. “It can be distinguished from encephaloid cancer by the absence of a fibrous stroma, by the uniformity in the character of its cells, and by the absence of any invasion of the surrounding structure in their growth other than the connective tissue from which they grow.”

The _Spindle-celled Sarcoma_, called also the fibro-plastic and recurring fibroid, is most closely allied to the fibroma. It consists essentially of fusiform cells, with well-marked nuclei and thin processes, sometimes split at the end. They are nearly in close contact, there being but little intercellular substance. The cells are parallel and arranged in bundles, which pass in all directions through the growth. “When cut, this sarcoma grates under the knife, and the surface exhibits a firm, tough, greyish or pale-yellowish appearance, similar to that of ordinary fibrous growth. After removal, they are softer and more succulent when they recur.”

They grow from the periosteum, the fasciæ, and from the connective tissue in other parts. They are more frequently enclosed in a capsule than the other varieties.

The _Giant-celled Sarcoma_, called also the _myeloid_ sarcoma, most frequently occurs in connection with bone. They consist of large, many nucleated cells, mingled with round or spindle forms, nearly in contact, there being but a sparse intercellular substance. On section, the surface appears smooth, compact, shining, greyish-white or greenish, with blotches of a dark crimson, brownish or pink hue.

The giant-celled sarcoma is not a benign affection, but is the least malignant of the sarcomas.

2. =Carcinomatous Tumors.= “The _Carcinomata_ are new formations, consisting of cells of an epithelial type, without any intercellular substance, grouped together irregularly within the alveoli of a fibrous stroma. The cells are characterized by their large size, by the diversity of their forms, and by the magnitude and prominence of their nuclei and nucleoli. In size they vary from ¹⁄₆₀₀ to ¹⁄₁₅₀₀ of an inch in diameter, the majority being about five times as large as a red blood-corpuscle. They are round, oval, fusiform, caudate, polygonal—exhibiting, in short, every diversity of outline. The nuclei, which are large and prominent, are round or oval in shape, and contain one or more bright nucleoli.” There is generally but a single nucleus, two, however, are often met with, and they are even still more numerous in the soft varieties of cancer.

The stroma varies in amount. It consists of a fibrillated tissue, forming by their peculiar arrangement, alveoli of various sizes and shapes, in which the cells are grouped. The stroma varies in character according to the rapidity of its growth. Where its growth is rapid, it will contain numerous round and spindle-shaped cells; where it is slow, or has ceased altogether, the tissue will contain but few cells, and will be dense and fibrous in character. The latter condition is most frequently met with.

The blood-vessels are sometimes very numerous, and are always limited to the stroma, and never encroach upon the alveoli. This serves to distinguish the carcinomata from the sarcomata, since in the latter the blood-vessels ramify amongst the cells of the growth.

The carcinomata also possess lymphatics, and it is owing to this that the lymphatic glands are so constantly involved in the disease.

Cancers very rarely become encapsuled, but generally invade the surrounding structures. The epithelial elements are found infiltrating the tissues for some distance around the tumor, so that there is no line of demarcation between it and the normal structures.

Carcinomatous tumors are liable to certain alterations and transformations, like other morbid growths.

Fatty degeneration is the most common of these. This occurs to a greater or less extent in all the varieties of cancer. It produces softening of the growth, which is often reduced to a pulpy, cream-like consistence.

Calcareous degeneration has been occasionally met with in encephaloid, and in carcinoma invading bone.

Inflammation, softening, and consequent ulceration, are not unfrequent.

The varieties of carcinomata are:

(_a_.) _Scirrhus._ Scirrhus, fibrous, hard or chronic cancer, seldom occurs before middle age, and more frequently in the female than male.

The liver, mammæ and uterus, are particularly liable to be attacked. It also occurs in the alimentary canal, and in the skin.

Scirrhus is characterized by the large amount of its stroma, and its slow growth. The tumor is firm, hard and inelastic, of variable shape, and is often depressed in the centre, owing to the contraction of the cicatricial tissue.

On section, especially in the more matured stages, the tumor exhibits a whitish, glistening aspect, intersected with fibrous bands, the remains of normal tissue, changed by disease. It yields on being scraped, a peculiar fluid, the so-called cancer juice, generally of a pale, grayish, turbid appearance, rich in cells, nuclei and granules, sometimes of a whitish, creamy hue. This juice is evidently the result of disintegration, and is hence but sparingly present in recent specimens. It readily mixes with water, and often contains a quantity of free oil.

Scirrhus has but few blood-vessels. Nerves and lymphatics also exist. It has a tendency to ulcerate, and to contract adhesions with the structures surrounding it. The lymphatic glands are also liable to be infected, by the conveying of cancer elements to them through the lymphatic vessels situated in the scirrhus mass.

(_b._) _Encephaloid._ Encephaloid, medullary, soft or acute cancer, differs from the preceding, in the small amount of stroma, the consequent softness of consistence, and its rapid growth.

It is most common in the mammæ, eye, testicle, uterus, liver, lymphatic glands, periosteum and bones. The greatest number of cases occur between the twentieth and fiftieth years.

The cells are exactly similar to those of scirrhus, but far more numerous, while the stroma is not so well marked, and much less fibrous, and does not undergo a similar cicatricial contraction.

Blood-vessels are very abundant.

The tumor varies in size from a pea to that of an adult’s head, its shape being generally ovoidal, and its surface more or less lobulated. “It is of a soft, brain-like consistence, the central portions; where fatty degeneration is most advanced, often being completely diffluent. On section, it presents a white, pulpy mass, much resembling brain substance, which is often irregularly stained with extravasated blood.”

Occasionally these tumors contain serous cysts of small size, as well as other adventitious products. When ulceration takes place; the sore is characteristic. “Its edges are thin, undermined, jagged, or irregular, while its bottom has a foul, bloody, fungous appearance. The parts around are of a deep red, livid, or purple color.”

(_c._) _Melanosis._ Melanotic, or black cancer, is probably merely the result of a pigmentation of the encephaloid. It occurs most frequently in the eye and skin, and is occasionally met with in the viscera. The melanotic matter occurs in small masses, of a rounded, ovoidal, or irregular shape, with or without a cyst, from the size of a pin’s head to that of a walnut; of a dull, sooty, brownish, or black color. They are generally invested by a distinct capsule, formed out of the cellular tissue in their immediate vicinity.

“Under the microscope, it is seen to consist of a fibrous net-work, including numerous alveoli, filled with free, unadherent pigment cells, occupied by colored granules, a few of the larger or older ones containing sometimes a nucleus with its nucleolus. Free pigment granules are also found in great abundance.”

(_d._) _Colloid._ The colloid, alveolar, gelatiniform cancer, is the most uncommon form of heterologous formations. It is regarded by some, as simply one of the preceding forms which has undergone mucoid or colloid change.

It is most frequently met with in the stomach, the intestines, and the periosteum; and can appear at any age, but is most common between the thirty-fifth and fiftieth year.

The tumor varies in size, from the size of a marble to an adult head, is globular or irregular in shape, of a firm, dense consistence, with a rough, knobby, or distinctly lobulated surface.

The stroma, of a fibrous character, of a dull, whitish, grayish, or pale-yellowish color, and great density, is so arranged as to form numerous alveoli of various sizes and shapes, communicating with each other. Within these cavities is contained the gelatinous or colloid material, which is a glistening, whitish, greenish, or yellowish color, and of the consistence of thin mucilage or ordinary jelly. In the older cells it becomes more firm and opaque. “In the main, it is perfectly structureless; within it, however, are imbedded a varying number of spherical cells, which also contain the same gelatinous substance. These cells present a peculiar appearance; they are large and spherical in shape, and are distended with drops of the same gelatinous material as that in which they are imbedded. Many of them display a lamellar surface, their boundary consisting of concentric lines.”

(_e._) _Epithelioma._ Epithelioma, cancroid, or epithelial cancer, grows in connection with cutaneous and mucous surfaces.

The cells, usually containing a single nucleus, resemble very closely those met with in the cutaneous surfaces, and in the mucous membrane of the mouth, only that they are larger, their average being about ¹⁄₇₀₀ of an inch. In shape they are either rounded, oval, angular, or elongated, according to the pressure to which, in their growth, they are subjected. They are closely packed together into nests, assuming a concentric arrangement, like the layers of an onion.

Mixed up with the cells, especially if the growth have made much progress, are great numbers of free nuclei and granules, and sometimes also crystals of cholesterine, pigment cells and blood corpuscles.

“The tumor itself is firm in consistence, more or less friable, and on section presents a grayish-white granular surface, intersected with lines of fibrous tissue. The cut surface yields on pressure, a small quantity of turbid fluid, and in most cases also a peculiar thick, crumbling, curdy material, can be expressed, which comes out in a worm-like shape, like the sebaceous matter from the glands of the skin.” The ulcer formed has a foul, fungating appearance, with irregular granulated edges, and a hard rough base.

The disease is more common in men than women, and seldom occurs before the age of thirty-five or forty. It is most frequently met with in the lower lip, in the tongue, prepuce, scrotum, (“chimney-sweep’s cancer,”) labia, eyelids, cheeks, in the uterus and bladder. As it extends it may involve any tissue.