See also:

• TUMOUR (Lat. tumor, a swelling)

TUMOUR (See also:

• LAT

Lat. tumor, a swelling)  , a See also:

• TERM

term applied, from the earliest See also:

• PERIOD
• PERIOD (Gr. irepioSos, a going or way round, circuit, aepi, round, and &Sis, way, road)

period of medical literature, to any swelling of whichthe nature and origin were unknown . Thus used in its most literal sense, the word is of purely clinical derivation and has no pathological significance of any See also:

• KIND (O. E. ge-cynde, from the same root as is seen in " kin," supra)

kind . Consequently a very heterogeneous collection of swellings have been described as tumours, including such diverse conditions as an See also:

• ABSCESS (from Lat. abscedere, to separate)

abscess, a tubercular gland, the enlarged See also:

• SPLEEN (Gr. o-1rXilv)

spleen of See also:

• MALARIA

malaria or a See also:

• CANCER (" THE CRAB ")
• CANCER, LUIS (d. 1549)
• CANCER, or CARCINOMA (from Lat. cancer, Gr. KapKivwga, an eating ulcer)

cancer . With the progress of See also:

• BACTERIOLOGY

bacteriology and the improved technique of See also:

• HISTOLOGY
• HISTOLOGY (Gr. Ler6c, web, tissue, properly the web-beam of the loom, from iQravai, to make to stand)

histology it has been found possible, however, tp See also:

• SEPARATE

separate these various " swellings " into certain See also:

• GROUPS
• GROUPS, THEORY

groups: (1) Inflammatory or Infective Tumours; (2) Tumours due to See also:

• HYPERTROPHY (Gr. inrEp, over, and rpo(A, nourishment)

Hypertrophy; (3) Cysts; (4) Spontaneous Tumours, or Tumours proper . The tendency of See also:

• MODERN

modern See also:

• CONVENTION (Lat. conventio, an assembly or agreement, from convenire, to come together)
• CONVENTION, THE NATIONAL

convention is to restrict the use of the term " See also:

• TUMOUR (Lat. tumor, a swelling)

tumour " to the last See also:

• GROUP

group, but for the See also:

• SAKE

sake of completeness it is necessary to See also:

• TOUCH (derived through Fr. toucher from a common Teutonic and Indo-Germanic root, cf. " tug," " tuck," O. H. Ger. zucchen, to twitch or draw)

touch briefly on the distinguishing features of the first three groups . 1 . Inflammatory or Infective Tumours.—These have certain characteristics which separate them sharply from other classes of tumour . In the first See also:

• PLACE (through Fr. from Lat. platea, street; Gr. IrAar6s, wide)

place all of them are due to the irritative See also:

• ACTION

action of some micro-organism (see See also:

• PATHOLOGY (from Gr. raBos, suffering)

PATHOLOGY) . Inflammation due to microbial action always follows a typical course . First, a number of wandering cells derived from the See also:

• BLOOD

blood, the See also:

• LYMPH

lymph or the connective tissues make their way to the site of irritation, and thus produce the red, painful swelling with which every one is See also:

• FAMILIAR (through the Fr. familier, from Lat. familiaris, of or belonging to the familia, family)

familiar . A struggle now ensues between these cells and the invading bacteria; if the victory rests with the former, the inflammation gradually subsides, and the swelling disappears in course of See also:

• TIME (0. Eng. Lima, cf. Icel. timi, Swed. timme, hour, Dan. time; from the root also seen in " tide," properly the time of between the flow and ebb of the sea, cf. O. Eng. getidan, to happen, " even-tide," &c.; it is not directly related to Lat. tempus)
• TIME, MEASUREMENT OF
• TIME, STANDARD

time . But if the bacteria gain the upper See also:

• HAND
• HAND (a word common to Teutonic languages; cf. Ger. Hand, Goth. handus)
• HAND, FERDINAND GOTTHELF (1786-185r)

hand a number of the cells are killed, undergo liquefaction and are converted into pus, so that an abscess results .

Thus an inflammatory swelling may be solid or fluid according to the severity of the irritant . The See also:

• COMMON

common inflammatory bacteria--staphylococcus and streptococcus—cause suppuration in the See also:

• MAJORITY (Fr. majorite; Med. Lat. majoritas; Lat. major, greater)

majority of cases, but there are a few organisms such as streptothrix, spirochaeta pallida, and in many instances the tubercle bacillus, which set up an inflammation of an extremely chronic type, rarely progressing to the formation of pus, but leading rather to the development of a hard, solid See also:

• MASS (O.E. maesse; Fr. messe; Ger. Messe; Ital. messa; from eccl. Lat. missa)
• MASS, IN

mass of very slow growth, that may persist for months or even years . To the naked See also:

• EYE
• EYE (O. Eng. edge, Ger. Auge; derived from an Indo-European root also seen in Lat. oc-ulus, the organ of vision (q.v.)

eye these solid inflammatory swellings may closely simulate the spontaneous tumours with which they have been often confused, but a microscopical examination will correct the See also:

• MISTAKE (i.e. take amiss)

mistake in nearly every See also:

• CASE
• CASE, JOHN (d. 1600)

case . For the See also:

• MINUTE
• MINUTE (Lat. minutes, small; minuere, to make less)

minute structure of the infective tumours, whatever their situation, is almost identical; they consist merely of an irregular collection of inflammatory cells; and this of itself is sufficient to See also:

• MARK
• MARK, CARL (1858– )
• MARK, GOSPEL OF ST
• MARK, ST

mark them off quite distinctly from the group of tumours proper, which, as will presently be seen, vary widely in structure according to the See also:

• TISSUE (Fr. tissu, tissue, participle of tisser, Lat. texere, to weave)

tissue from which they See also:

• SPRING (from " to spring," " to leap or jump up," " burst out," O. Eng., springau, a common Teut. word, cf. Ger. springer, possibly allied to Gr. QnrFpxecOac, to move rapidly)

spring, and show a resemblance to the See also:

• PARENT, SIMON NAPOLEON (1855– )

parent type at once characteristic and See also:

• PECULIAR

peculiar . To this statement there is one exception, for a See also:

• FORM (Lat. forma)

form of See also:

• MALIGNANT (Lat. malignus, evil-disposed, from maligenus)

malignant tumour, known as a sarcoma, may See also:

• BEAR
• BEAR, BLACK
• BEAR, BROWN
• BEAR, GRIZZLY
• BEAR, ISABELLINE
• BEAR, WHITE

bear a very deceptive likeness to an inflammatory swelling . 2 . Hypertrophic Tumours.—A tissue or See also:

• ORGAN

organ is said to be hypertrophied when it is increased in See also:

• SIZE

size but remains normal in structure . The most familiar example is the hypertrophy of the skeletal muscles that follows increased use, or the hypertrophy of the See also:

• HEART
• HEART, LUNG

heart muscle which See also:

• HELPS, SIR ARTHUR (1813-1875)

helps to compensate the faulty action of the valves . But neither of these constitutes a hypertrophic tumour . For an instance of this we must turn to the enlargement of the spleen that occurs in malaria and certain forms of See also:

• ANAEMIA (from Gr. ay-, privative, and aiµa, blood)

anaemia, of the See also:

• THYROID (Gr. Ovpoea3i'is, shield-shaped, from Ovpeos, a large oblong shield, shaped like a door, Obpa, and eiSos, form)

thyroid gland in See also:

• GOITRE (from Lat. guttur, the throat; synonyms, Bronchocele, Derbyshire Neck)

goitre, and of the lymphatic glands in See also:

• HODGKIN, THOMAS (1831- )

Hodgkin's disease . In each of these conditions there is merely an increase of apparently normal tissue, and from a microscopical examination of the hypertrophied organ it would be impossible to say that it was other than healthy . The enlargement of the spleen and of the thyroid in these cases are overshadowed by certain changes in the blood and in the See also:

• NERVOUS

nervous See also:

• SYSTEM

system which constitute a distinct disease; but in Hodgkin's disease there are no specific symptoms apart from the swelling of the glands, and it has been suggested that this may be due either to the action of some micro-organism which has hitherto escaped detection, or to a widely diffused growth of a sarcomatous type .

If the former supposition be correct these glandular swellings must be classed with the infective tumours; if the latter they should be regarded as spontaneous tumours . There is, at See also:

• PRESENT

present, no agreement on this point, and they have, therefore, been described here as hypertrophic tumours . 3 . Cysts.—A cyst may be defined as a collection of fluid surrounded by a See also:

• WALL (O. Eng. weal, weall, Mid. Eng. wal, wane, adapted from Lat. vallum, rampart; the original O. Eng. word for a wall was wag or tenth)
• WALL, RICHARD (1694-1778)

wall or See also:

• CAPSULE (from the Lat. capsula, a small box)

capsule . The nature of the fluid varies according to the site and origin of the cyst ; the cyst-wall is usually composed of a tough layer of fibrous tissue . Cysts arise by the See also:

• DILATATION (from Lat. dis-, distributive, and lotus, wide)

dilatation of a pre-existing space with fluid ; and when, as often happens, the cyst-wall is tensely stretched by the pressure of the fluid within, they may easily be mistaken for solid tumours . The number and variety of cysts are very See also:

• GREAT

great, and they are only mentioned here on See also:

• ACCOUNT
• ACCOUNT (through O. Fr. acont, Late Lat. comptum, cornputare, to calculate)

account of the errors in diagnosis for which the are often responsible . For further details the reader should consu . the See also:

• SPECIAL

special textbooks . 4 . Spontaneous Tumours, or Tumours Proper (synonyms: Neoplasm, New Growth).—The following See also:

• DEFINITION (Lat. definitio, from de-finire, to set limits to, describe)

definition of a spontaneous tumour suggested by Ziegler is perhaps the most satisfactory: " A neoplasm or tumour is a new formation of tissue, which is atypical in structure, serves no useful purpose to the whole See also:

• ECONOMY

economy, and the growth of which has no typical termination . " In this definition the words " new formation of tissue " exclude the cystic swellings; the attribute " atypical in structure " excludes hypertrophies; and the final clause " the growth of which has no typical termination " excludes all swellings of an inflammatory nature which progress, however slowly, towards either suppuration or See also:

• RESOLUTION

resolution and recovery . These tumours arise by the exaggerated and abnormal proliferation of a single See also:

• CELL (from Lat. cella, probably from an Indo-European kal —seen in Lat. celare, to hide; another suggestion connects the word with Lat. cera, wax, taking the original meaning to refer to the honeycomb)

cell, or a group of cells .

They increase in size solely by the multiplication of their own cells, and the only contribution which the surrounding tissues make to the progress is the formation of a " stroma, " or supporting framework of fibrous tissue; and even that is wanting in many cases . Inasmuch as the newly-formed cells of the tumour take on the likeness of the parent from which they are sprung, it follows that the minute structure of such a tumour, whatever its situation, will be a more or less exact copy of that of the tissue whence it originated . A tumour growing from the skin will therefore imitate the cell-structure of the normal skin; the resemblance of a See also:

• BREAST (a word common to Teutonic languages, cf. the Ger. Brust, possibly connected with an O. Sax. brustian, to bud)

breast tumour to the healthy breast is often so See also:

• CLOSE
• CLOSE (from Lat. clausum, shut)
• CLOSE, MAXWELL HENRY (1822-1903)

close as to make it a hard task to distinguish the one from the other; whilst the similarity of bony and cartilaginous tumours to true See also:

• BONE (a word common in various forms to Teutonic languages, in many of which it is confined to the shank of the leg, as in the German Bein)
• BONE, HENRY (1755-1834)

bone and See also:

• CARTILAGE (Lat. cartilage, gristle)

cartilage is evident to all . This See also:

• IMITATION (Lat. imitatio, from intitari, to imitate)

imitation of the parent type by the spontaneous tumours is one of their most remarkable characteristics, and provides a reliable criterion by which they may be separated from the inflammatory new growths, which are all built up on the same See also:

• GENERAL
• GENERAL (Lat. generalis, of or relating to a genus, kind or class)

general See also:

• PLAN
• PLAN (from Lat. planes, flat)

plan . Consequently it is almost always possible to determine the origin of a tumour from an examination of its histological appearances; and conversely we know that an See also:

• EPITHELIAL, ENDOTHELIAL

epithelial tumour will never spring from a connective tissue nor a connective tissue tumour from an epithelium . Another outstanding feature of the neoplastic tumours is that they See also:

• LEAD
• LEAD (pronounced iced)

lead an entirely See also:

• INDEPENDENT

independent existence subject to none of the restraints to which the normal cell must needs submit . These normal cells are, indeed, possessed of certain limited See also:

• POWERS, HIRAM (1805-1873)

powers of multiplication, by which they are enabled to replace the slight loss of tissue which the See also:

• WEAR

wear and See also:

• TEAR

tear of See also:

• LIFE

life perpetually entails; or, again, they can on occasion make See also:

• GOOD, JOHN MASON (1764-1827)

good a greater loss of substance, as in the healing of an See also:

• ULCER

ulcer, or the regeneration of a skin See also:

• WOUND (O. Eng. wund,connected with a Teutonic verb, meaning to strive, fight, suffer, seen in O. Eng. winnan, whence Eng. " win ")

wound . But these powers are confined within certain well-marked See also:

• BOUNDS, BEATING THE

bounds, which may not be transgressed . Contrast with this the tumour cell, emancipated from all See also:

• CONTROL (Fr. contrdle, older form contre rolle, from Med. Lat. contra-rotulus, a counter roll or copy of a document used to check the original; there is no instance in English of the use of " control " in this, its literal, meaning)

control and owning to no See also:

• RESTRAINT (from " to restrain," Lat. restringere, to hold back, prevent)

restraint . It is true that the See also:

• SIMPLE

simple tumours often remain stationary after attaining a certain size, but the general tendency of all tumours Is towards persistent and unlimited growth, and the cancer cell continues its career unchecked by everything See also:

• SAVE, or SAVA (Ger. Sau; Hungarian Szdva; Lat. Savus)

save See also:

• DEATH

death . The spontaneous tumours are seen in every tissue and organ of the See also:

• BODY

body, though in some they are relatively infrequent . Nor are they confined to See also:

• MAN
• MAN, ISLE OF (anc. Mona)

man, for they have been found throughout the vertebrate See also:

• KINGDOM

kingdom .

It is often stated that a higher See also:

• STATE
• STATE, GREAT OFFICERS OF

state of See also:

• CIVILIZATION

civilization has inflicted on See also:

• EUROPEAN

European races a greater susceptibility to tumour formation . As to this, reliable See also:

• EVIDENCE (Lat. evidentia, evideri, to appear clearly)

evidence is hard to obtain, but such a statement would seem to be only partially true, and the apparent See also:

• IMMUNITY (from Lat. immunis, not subject to a munus or public service)

immunity of certain native races is to some extent due to lack of sufficient observations . It is usual to separate these tumours into two groups: the Non-malignant, See also:

• INNOCENT (INNOCENTIUS)
• INNOCENT (POPES)

Innocent or Benign, and the Malignant or Cancerous . Of these two groups the latter are the more familiar and have attracted much more See also:

• ATTENTION (from Lat. ad-tendo, await, expect; the condition of being " stretched " or " tense ")

attention and study than the former, on account of the danger to life which they involve, but in point of See also:

• NUMBERS, BOOK OF
• NUMBERS, PARTITION OF

numbers they are greatly outweighed by the first group . Two or more non-malignant tumours, of the same or different varieties, are often found in the same individual; but with the cancers this is a rare occurrence, and such growths are usually single . The non-malignant tumours are usually rounded in shape . In size they vary enormously; a fibroid tumour may be as small as a See also:

• PEA (Pisum)

pea; a fatty tumour may weigh See also:

• FORTY

forty pounds . Often they cease growing after attaining a certain size, but there are very many exceptions to this, and it is seldom possible to predict the subsequent course of one of these growths . They possess, however, four See also:

• CONSTANT, BENJAMIN (1845-1902)

constant characteristics by which they may be distinguished from the malignant variety . i . A non-malignant tumour, whatever its size, remains localized to the See also:

• PART

part from which it originates . It is not an " infiltrating " growth, that is to say it does not eat its way into the surrounding tissues, but rather pushes them aside, and so may be called " expansive .

" Moreover, it is separated from them by a thin but usually well-marked layer of fibrous tissue known as the " capsule " of the tumour, which seems to be formed as the result of a slight inflammation that the presence of the tumour always causes among the healthy tissues surrounding it, and may be regarded as a protest on their part against the invasion of the tumour . 2 . Non-malignant tumours are not of themselves dangerous to life . They may, however, cause a great See also:

• DEAL

deal of See also:

• PAIN (from Lat. poena, Gr. robin, penalty, that which must be paid: O. Fr. peine)
• PAIN, BARRY (1867– )

pain and evendeath, when situated in some sensitive or delicate organ . For instance, a small tumour may cause intense pain by pressing on a See also:

• NERVE (Lat. nervus, Gr. vevpov, a bowstring)

nerve, or dropsical swelling of a See also:

• LIMB

limb by obstructing a vein, or death from suffocation by blocking the larynx . Nevertheless it remains true that any evil effects are due not to the nature of the tumour, but to its situation, whereas a cancer causes death whatever its position . 3 . These tumours never reproduce themselves in distant parts of the body . More than one may be present in the same individual; but each arises independently, and the widespread dissemination so typical of a cancerous growth is never seen . 4 . An innocent growth never recurs after operation . The boundaries of the growth are so well defined that See also:

• COMPLETE

complete removal is usually easy, and the operation is a simple and satisfactory proceeding .

Malignant Tumours, or Cancers.—T here are two varieties of malignant tumour: the Sarcomata, arising from the connective tissues; the Carcinomata, arising from epithelial tissues . It is customary to describe them both as cancers . The See also:

• MAIN (from the Aryan root which appears in " may " and " might," and Lat. magnus, great)
• MAIN (Lat. Moenus)

main features of these tumours are as follows: i . The Infiltrating Nature of a Malignant Tumour.—A cancer follows a course very different from that of an innocent tumour . Its growth has no appointed termination, but continues-with unabated vigour until death ; moreover, it is more rapid than that of the innocent tumours, and so does not permit of the formation of a capsule by the neighbouring tissues . In consequence such a tumour shows no well-defined boundary, but from its margin See also:

• FINE

fine tendrils of cancer cells make their way in all directions into the surrounding parts, which gradually become more and more involved in the See also:

• PROCESS

process . Thus a cancer of the breast will attack both the skin covering it and the underlying muscle and bone; a cancer of the See also:

• INTESTINE (Lat. intestinus, internal, usually in neuter plural intestina. from intus, within)

intestine will eat its way into the See also:

• LIVER (O. Eng. lifer; cf. cognate forms, Dutch lever, Ger. Leber, Swed. lefver, &c.; the O. H. Ger. forms are libara, lipora, &c.; the Teut. word has been connected with Gr. i'prap and Lat. jecur)

liver, spleen and See also:

• KIDNEY

kidney, until these See also:

• ORGANS

organs become to a great extent replaced by cancer cells, and can no longer perform their proper functions . 2 . Formation of Secondary Growths, or Metastases.—In addition to this spread of growth by See also:

• DIRECT

direct See also:

• EXTENSION (Lat. ex, out ; tendere, to stretch)

extension, another characteristic of malignant tumours is a tendency to dissemination, that is, to reproduce themselves in various parts of the body far removed trom the See also:

• ORIGINAL

original site; so that it is not unusual to find after death that a cancer of the breast has 'given rise to secondary, or metastatic, deposits in the lymphatic glands, the lungs, the ribs and other bones, the See also:

• BRAIN (A.S. braegen)

brain and the abdominal organs . These secondary deposits are due to the tumour cells making their way through. the walls of the small lymph and blood vessels and becoming detached by the force of the circulation, by which they are carried to some distant part of the body, there to continue their career of uncontrolled growth, The sarcomata and carcinomata differ somewhat as- regards the path of dissemination . The former are vascular tumours, well supplied with blood-vessels ; consequently dissemination usually occurs by way of the blood-stream rather than by the lymphatic circulation, and the commonest site for the secondary deposits of sarcoma is the See also:

• LUNG

lung . The carcinomata are less vascular, and the tendency of the growth is to invade the small lymph channels, so that the first signs of metastases are to be looked for in the lymphatic glands; at a later date these deposits may be spread throughout the body, particularly in the liver and other abdominal organs, the lungs and the bones .

The formation of metastases is of the utmost importance from a clinical point of view, as the success of an operation depends on the removal of all the secondary deposits as well as of the original growth . For instance, a few months after the first See also:

• APPEARANCE (from Lat. apparere, to appear)

appearance of a cancer of the breast the axillary lymph glands will be found to be hard and enlarged . This means that some of the cells of the See also:

• PRIMARY

primary growth have been carried in the lymph stream to these glands, and have begun to grow there; consequently any operation for the removal of the cancer of the breast must include the removal of these glands . If the breast tumour only be taken away the growth will continue unchecked in the glands . It is a See also:

• MATTER

matter of great difficulty to determine by the naked eye or the touch whether a gland is infected or not . In many cases where there is no evident enlargement the See also:

• MICROSCOPE (Gr. µucp6s, small, asenreiv, to %view)

microscope will show the presence of cancer cells ;and a certain See also:

• OPINION (Lat. opinio, from opinari, to think)

opinion can only be given after a microscopical examination . In operations for cancer of the breast or See also:

• TONGUE (O. Eng. lunge)

tongue the modern practice is to regard the lymphatic glands of the axilla or See also:

• NECK (O. Eng. hnecca; the word appears in many Teutonic languages; cf. Dutch ride, Ger. Nacken; in O. E. the common word was heals; cf. Ger. Hals)

neck respectively as infected in every case, however See also:

• EARLY
• EARLY, JUBAL ANDERSON (1816-1894)

early it be, and to remove them accordingly . In other parts of the body where the glands are inaccessible, the only See also:

• SOLUTION (from Lat. solvere, to loosen, dissolve)

solution of the difficulty is to urge the removal of the tumour at the earliest possible moment, before lymphatic infection has had time to occur . The frequency and rapidity of metastasis formation varies greatly . As a general See also:

• RULE

rule cancer of the breast is more liable than other forms of growth to be followed by widespread secondary deposits . On the other hand, in cases of cancer of the skin secondary infection is usually confined to the neighbouring lymphatic glands, and seldom occurs in any of the See also:

• INTERNAL

internal organs . 3 .

Termination of Malignant Tumours.—In one or two well authenticated cases a malignant tumour has disappeared of its 372 own See also:

• ACCORD (from Fr. accorder, to agree)

accord without any treatment, and a natural cure may be said to have occurred . But these form such an infinitesimal proportion of the whole that they do not affect the general truth of ,the statement that .the universal tendency of a malignant tumour is to cause death . Although the separation of the new growths into two groups is supported by certain fairly definite characteristics, both clinical and histological, yet it seems likely that the difference between them is one of degree rather than of kind . There is every See also:

• REASON (Lat. ratio, through French raison)

reason to believe that the same perverted impulse may give rise either to an innocent or a cancerous growth, the issue depending in part on the intensity of the impulse, and in part on the resisting powers of the tissues in which the incipient tumour cells See also:

• LIE, JONAS LAURITZ EDEMIL (1833—1908)
• LIE, MARIUS SOPHUS (1842–1899)

lie . Such a See also:

• HYPOTHESIS (from Gr. inrorcOivat, to put under; cf. Lat. suppositio, from sub-ponere)

hypothesis is supported by the See also:

• ANALOGY (Gr. avaXo-yLa, proportion)

analogy of the microbial infections, where the final outcome of life or death depends no less on the defensive mechanism of the individual than on the virulence of the infecting organism . Again, it is beyond doubt that occasionally a tumour, which for years has been void of the least taint of malignancy, may become converted into an active cancer . Moreover, certain tumours seem to lie on the border See also:

• LINE

line, for example, rodent ulcers and cancers of the parotid gland . These are malignant in that they are undoubtedly infiltrating tumours, they are innocent in that they never form metastatic deposits . Therefore it seems that malignancy or the See also:

• REVERSE

reverse is not to be regarded as an See also:

• ABSOLUTE (Lat. absolvere, to loose, set free)

absolute and constant attribute of any particular tumour or class of tumours, but rather as an expression of the See also:

• BALANCE (derived through the Fr. from the Late Lat. bilantia, an apparatus for weighing, from bi, two, and lanx, a dish or scale)

balance struck in the conflict between the opposing forces of the tumour and its See also:

• HOST

host . Histology of Tumours.—On examining a microscopical preparation of an epithelial tumour it is found to be built up of two distinct elements . There are the epithelial cells, which form the essential part of the tumour; there is a network of fibrous connective-tissue cells, which acts as a supporting framework to the epithelial elements, and is known as the stroma of the tumour . This twofold structure is seen in all the epithelial tumours, both non-malignant and malignant, and in the case of the latter it is a general rule that the greater the proportion of epithelial to connective-tissue elements the faster will the tumour grow .

On the other hand in the connective-tissue tumours (with the exception of the sarcomata) this See also:

• COMPOUND
• COMPOUND (from Lat. componere, to combine or put together)

compound structure is absent and there is only one type of cell present; thus a fatty tumour consists merely of See also:

• FAT (O.E. fdett; the word is common to Teutonic languages, cf. Dutch vet, Ger. Fett, &c., and may be ultimately related to Greek Irian, and =apos, and Sanskrit pivan)

fat cells; a bony tumour of bone cells, and so on . To understand clearly the See also:

• DIFFERENCES, CALCULUS OF (Theory of Finite Differences)

differences and likenesses that obtain between the malignant and the non-malignant new growths it is necessary to compare the histology of the two groups . See also:

• FIGS

Figs. ta, lb represent an innocent tumour (adenoma) of the breast . Figs . 2a, 2b a cancer (spheroidal-celled carcinoma) of the breast . Fig . 3 an innocent tumour (papilloma) of the skin . Fig . 4 a cancer of the skin . —c a, Tumour; b, normal breast tissue; c, underlying See also:

• MUSCULAR

muscular tissue . (See also:

• DRAWN

Drawn from an actual specimen.) a, Tumour cells; b, fibrous connective tissue . In the adenoma the individual cells bear the closest resemblance to the glandular cells of the normal breast from which they are derived .

In addition they tend to follow the normal very closely in their arrangement, so that at times it is difficult or impossible todecide which is tumour and which is healthy breast substance . Finally the growth is surrounded by a well defined capsule of fibrous tissue . ///1//////I//.//Oi a, Tumour; b, normal breast tissue; c, muscle . (Drawn from an actual specimen.) a, Tumour cells; b, stroma . In the carcinoma, the individual resemblance'is present, though less conspicuous, as many of the cells are irregular in size and shape . But the similarity of the arrangement is very hard to make out or even absent . The cells are arranged in disorderly masses; they are not enclosed by any semblance of a capsule, but tend to transgress their proper boundaries and invade the underlying muscles . Figs . 3 and 4 show analogous changes in an innocent and in a malignant tumour of the skin . a, Normal skin. d, Muscular tissue . b, Epithelium or epidermis. e, Papilloma . c, Connective tissue .

Speaking generally it may be said that the cells of an adenoma are fully differentiated and typical of the normal, whereas the cells of a carcinoma show less perfect differentiation, are in some degree atypical and resemble rather the actively growing cells found at an early See also:

• STAGE (Fr. 6/age; from Lat. stare, to stand)

stage of embryonic life . But it is in the cells of a sarcoma that the widest departure from type is seen . A sarcoma is a malignant growth arising from connective tissue, but the resemblance to adult Connective tissue is almost non-existent and the cells are essentially of an embryonic type . These differences between the innocent and the malignant cell bear out the well-established physiological rule that the less the functional development of a cell or tissue the greater its See also:

• POWER [WILLIAM GRATTAN] TYRONE (1797-1841)

power of growth . The See also:

• PRIMITIVE

primitive impulse is growth, which gives place at a later stage to the development of See also:

• FUNCTION

function . In theory it is always possible to distinguish with certainty between an innocent tumour and a cancer by means of the microscope . In practice this is, unfortunately, not the case . There are some tumours whose histological appearances seem to be on the border-line between the two conditions, and often these are the very cases in which the clinical features give no direct See also:

• CLUE

clue to their nature . In such circumstances it is only by taking into See also:

• CONSIDERATION (from Lat. considerare, to look at closely, examine, generally taken to be from con-, and the base seen in sidus, sideris, a star, the word being supposed to be originally an astrological or astronomical term)

consideration every detail, both clinical and pathological, that an opinion can be formulated, and even then it remains to some extent a matter of guess-See also:

• WORK

work . The See also:

• CAUSATION

Causation of Tumours.—An enormous number of suggestions as to the causation of tumours have been put forward from time to time . Many of these were at the outset quite untenable, and reference can only be made here to the more important . First in point of time came See also:

• VIRCHOW, RUDOLF (1821-1902)

Virchow's hypothesis that tumours arise as the direct result of irritation or injury .

Many examples of such a sequence of events are familiar to everybody . A cancer of, the See also:

• LIP (a word common in various forms, to Teutonic languages, cf Ger. Lippe, Dan. laebe; Lat. labium is cognate)

lip or tongue will often follow the irritation of a See also:

• CLAY (from O. Eng. claeg, a word common in various forms to Teutonic languages, cf. Ger. Klei)
• CLAY, CASSIUS MARCELLUS (1810-1903)
• CLAY, CHARLES (1801–1893)
• CLAY, FREDERIC (1838–1889)
• CLAY, HENRY (1777–1852)

clay See also:

• PIPE

pipe or a jagged tooth; a tumour of the breast is often attributed to a See also:

• BLOW, JOHN (1648-1708)

blow . But, on the other hand, there must be innumerable instances in which such a cause of irritation has not been followed by a tumour; and it is necessary to See also:

• DISCOUNT

discount the natural anxiety of mankind to seek a cause for every unexplained occurrence, so that a slight injury which under See also:

• ORDINARY (med. Lat. ordinarius, Fr. ordinaire)

ordinary circumstances would be forgotten-.is branded as the undoubted cause of any tumour that may subsequently make its appearance . As a complete explanation Virchow's hypothesis is insufficient, but it is quite probable that irritation may have an See also:

• ACCESSORY

accessory or predisposing See also:

• INFLUENCE (Late Lat. influentia, from influere, to flow in)

influence in tumour formation, and that it may be enough finally to upset the balance of a group of cells, which for some other reason were already hovering on the brink of abnormal growth . There is one peculiar ,form or irritation that demands special attention, that is exposure to the X rays . It is beyond doubt that exposure to these rays will cause cancerous ulceration of the skin; though what is the constituent of the rays that produces this effect is not known . Fortunately the danger can be obviated by the use of See also:

• RUBBER, INDIARUBBER

rubber gloves . Cohnheim's Hypothesis of Embryonic Remnants.—According to Cohnheim more cells are produced in embryonic life than are required for the development of the body, and a remnant is See also:

• LEFT

left unappropriated . Owing to their embryonic nature, these cells possess an exaggerated power of proliferation, and if at a later period of life this should be roused into activity by some See also:

• MECHANICAL

mechanical or other form of stimulus, their See also:

• RATE

rate of growth will outstrip that of the adult cells and a tumour will develop . As with Virchow's so with Cohnheim's hypothesis . It is at best only a partial explanation which may be applicable to a small proportion of tumours; and it could never account for X-See also:

• RAY (Lat. raia)
• RAY (or WRAY, as he wrote his name till 1670), JOHN (1628-1705)

ray cancer, or the inoculability of See also:

• MOUSE

mouse cancer . The Parasitic hypothesis is still a matter of keen debate .

In some degree cancer with its localized primary growth and widespread secondary deposits resembles certain infective diseases of microbial origin, such as pyaemia, where from a small primary site of infection the bacteria become disseminated throughout the body . From this analogy it was argued that tumour formation was due to the activityof some See also:

• PARASITE (From Gr. irapa, beside, Tiros food)

parasite . But if the mode of dissemination of a cancer and of a micro-organism be carefully examined this analogy is found to be false . When a micro-organism lodges in a gland or other part of the body, by its irritative action it stimulates the cells of that gland to increased activity, and any swelling that occurs is produced by the proliferation of those cells . But when a group of cancer-cells is deposited in a gland the subsequent growth arises entirely from the multiplication of those cancer-cells, and the gland cells take no part whatever in its formation . A very large number of organisms both See also:

• ANIMAL
• ANIMAL (Lat. animalis, from anima, breath, soul)

animal and See also:

• VEGETABLE

vegetable have been described as occurring in tumours; and some of these have been cultivated on artificial See also:

• MEDIA

media outside the body; but to none of them can any direct causal relationship with cancer be attributed . One of the best authenticated, a small coccus, known as Micrococcus neoformans can certainly be cultivated from many tumours malignant and innocent, and it has been suggested that it may be responsible for the slight inflammatory changegthat occur in the See also:

• NEIGHBOUR (O. Eng. neahgebiir, from Walt, " nigh," " near ")

neighbour-See also:

• HOOD,
• HOOD, JOHN BELL (1831–1879)
• HOOD, SAMUEL HOOD, VISCOUNT (1724–1816)
• HOOD, SIR SAMUEL (1762-1814)
• HOOD, THOMAS (1799-1845)
• HOOD, TOM (1835–1874)

hood of most new growths . The final and See also:

• CRITICAL (in alphabetical order of authors)

critical test of the connexion of an organism with some diseased See also:

• CONDITION (Lat. condicio, from condicere, to agree upon, arrange; not connected with conditio, from condere, conditum, to put together)

condition is the See also:

• PRODUCTION (Lat. productionem, from producere, to pro-duce)

production of a similar condition in animals by inoculation of that organism, and this experiment has signally failed with all the suggested cancer parasites . Another very cogent See also:

• ARGUMENT

argument against the infective hypothesis is the fact that although tumours of identical structure are found throughout the vertebrate kingdom, it has never yet been found possible artificially to transmit these tumours from one See also:

• SPECIES

species to another . If they were of an infective nature it is almost inconceivable that the See also:

• GAP

gap between two allied species should be such an insuperable See also:

• BAR
• BAR (0. Fr. barre, Late Lat. barra, origin unknown)
• BAR, CONFEDERATION OF
• BAR, FRANCOIS DE (1538-1606)
• BAR, THE

bar to transmission . Quite recently Borrel of the See also:

• PASTEUR, LOUIS (1822-1895)

Pasteur See also:

• INSTITUTE (from Lat. instituere, to establish or set up)

Institute has stated that certain animal parasites from the skin are often to be found buried in the cell masses of cancers of the skin and breast, and he thinks, that these parasites may be the See also:

• CARRIERS

carriers of some as yet unknown cancer See also:

• VIRUS, CHRISTOBAL DE (1550?-1615?)

virus, just as the See also:

• MOSQUITO (Span. mosquito, a gnat, diminutive of mosca, a fly)

mosquito is the See also:

• CARRIER
• CARRIER, JEAN BAPTISTE (1956-1794)

carrier of malaria . Ribbert has suggested that tumour formation may be due to " alteration of tissue tension." In his opinion the various cells of the body are normally held in a state of See also:

• EQUILIBRIUM (from the Lat. aequus, equal, and libra, a balance)

equilibrium by some condition of mutual interdependence amongst themselves .

Should this equilibrium be disturbed some of 'these cells may See also:

• ESCAPE (in mid. Eng. eschape or escape, from the O. Fr. eschapper, modern echapper, and escaper, low Lat. escapium, from ex, out of, and cappa, cape, cloak; cf. for the sense development the Gr. iichueoOat, literally to put off one's clothes, hence to sli

escape from the controlling influence usually exercised upon them by their neighbours, and become endowed with greatly enhanced powers of growth . Adami considers that every cell possesses two distinct properties, a See also:

• PROPERTY

property of function and a property of growth, and he regards these as incompatible, that is to say, a cell cannot at the same time be carrying out a specific function and also undergoing active growth . He believes that on occasion some of these cells may abandon their " See also:

• HABIT (through the French from Lat. habitus, from habere, to have, hold, or, in a reflective sense, to be in a certain condition; in many of the English senses the French use habitude, not habit)

habit of work " ,and assume a " habit of growth," and this will lead to the development of a tumour . Neither of the two latter explanations brings us very much nearer the solution of the question—they merely place the unknown See also:

• FACTOR (from Lat. facere, to make or do)

factor one step farther back; but they serve to emphasize the biological aspect of the problem . At the present time the general See also:

• WEIGHT

weight of evidence seems to favour the See also:

• IDEA (Gr. Ibia, connected with i&eiv, to see; cf. Lat. species from specere, to look at)

idea that tumour formation is due to some See also:

• INTRINSIC (through Fr. intrinsique, from Lat. intrinsecus, inwardly; inter, within, secus, following, from root of sequi, to follow)

intrinsic cause, whereby the normal processes of growth are disturbed, rather than to any extrinsic cause such as microbial infection . Therefore it is from a careful study of the See also:

• LAWS

laws of growth, and from See also:

• RESEARCH (O. Fr. recerche, from recercher, re- and cercer, mod. chercher, to search; Late Lat. circare, to go round in a circle, to explore)

research directed along broad biological lines that the best results are to be looked for in the future . See also:

• CLASSIFICATION (Lat. classis, a class, probably from the root cal-, cla-, as in Gr. icaMce, clamor)

Classification of Spontaneous Tumours.—So little is known as to the nature of these tumours that a satisfactory classification on a scientific basis is not yet within reach . The following is merely suggested as convenient I.—Connective-tissue Tumours . Innocent . Malignant . Lipoma (fatty tumour) . Fibroma (fibrous tumour) .

Sarcoma . Myoina (muscular tumour) . Endothelioma . Osteoma (bony tumour) . Chondroma (cartilaginous tumour) . Odontoma (tumour in connexion with See also:

• TEETH (O.E. Eel); plural of tooth, O.E. top)

teeth) . Myxoma (mucoid tumour) . Neuroma (tumour in connexion with nerves) . Glioma (neuroglial tumour) . Endothelioma (endothelial tumour) . Angioma (tumour composed of blood vessels) . I I.Epithelial Tumours .

Innocent . Malignant . Papilloma . Carcinoma . Adenoma . Rodent Ulcer . I . Connective-tissue Tumours.'—Lipoma (fig . 5).—Of the connective-tissue group the fatty tumours are the most common . They often arise from the layer of fat beneath the skin, and a usual site for these subcutaneous lipomata is the back of the See also:

• TRUNK (Fr. tronc, Lat. truncus, cut off, maimed)

trunk, though at times they are found on the limbs and elsewhere . They i Figs. g, 6, 7, 8, 9, 14, 15 and 17 have been redrawn from Bland See also:

• SUTTON
• SUTTON, SIR RICHARD (d. c. 1524)
• SUTTON, THOMAS (c. 1532—1611)

Sutton's Tumours, by permission; figs . 1o, II, 12 and 13 are from See also:

• ROSE
• ROSE (Rosa)
• ROSE, GEORGE (1744-1818)
• ROSE, HUGH JAMES (1795—1838)
• ROSE, WILLIAM STEWART (1775-1843)

Rose & Carless, See also:

• SURGERY
• SURGERY (Fr. chirurgie, from Gr. Xetpoupyfa, i.e. hand-work)

Surgery, by permission .

are soft, painless swellings, sometimes of great size; though usually single, as many as a dozen may be present in the same individual . Lipomata are also found in the abdominal cavity, growing from the subperitoneal layer of fat . Fm . 5.—Lipoma of the See also:

• PALM (Lat. palma, Gr. iraX6.jn )
• PALM, JOHANN PHILIPP (1768-1806)

palm.' What is known as a diffuse lipoma (fig . 6) consists of a generalized overgrowth of the subcutaneous fat of the neck, and this may be so extensive as to obliterate the outline of the See also:

• JAW (Mid. Eng. jawe, jowe and geowe, O. Eng. cheowan, connected with " chaw " and " chew," and in form with " jowl ")

jaw . Fibroma (fig . 7).-0f tumours containing fibrous tissue, by far the most important are the fibroids of the uterus . A better name for these tumours would be Fibromyomata, as they always contain a varying proportion of muscle See also:

• FIBRES
• FIBRES (or FIBERS, in American spelling; from Lat. fibra, apparently connected either with filum, thread, or findere, to split)

fibres . They origi- nate in the wall of the uterus, but generally come to project either internally into the cavity of the uterus, or ex- ternally into the peritoneal cavity; and often their See also:

• SOLE (Solea)

sole connexion with the uterine wall is a stalk or pedicle formed from the capsule of the tumour . Fibromyomata of the uterus are most com- mon from 35 to 45 years of See also:

• AGE (Fr. age, through late Lat. aetaticum, from aetas)

age ; in girls under 20 they are almost unknown . They may attain a great size and are often multiple . They seem to be equally common in married and unmarried cases they are discovered by See also:

• CHANCE (through the O. Fr. cheance, from the Late Lat. cadentia, things happening, from cadere, to fall out, happen; cf. " case ")

chance or not until after death .

On the other hand they may giverise to severe symptoms, and that in many different ways . First, they may cause See also:

• HAEMORRHAGE (Gr. atµa, blood, and prryvvvac, to burst)

haemorrhage prolonged over years so that the See also:

• HEALTH

health is entirely ruined . Secondly, they may become inflamed and septic, and lead to severe blood-poisoning . Next, for some unknown reason, a fibroid tends to prevent conception, whilst, should pregnancy occur, labour is greatly impeded . Finally, it seems to be established that a fibroid may occasionally become converted into a sarcoma . Examples of pure fibrous tissue tumours are the small multiple growths of the subcutaneous tissue, known as Painful subcutaneous nodule, and the irregular outgrowth from the See also:

• GUM (Fr. gomme, Lat. gommi, Gr. Kµµ1, possibly a Coptic word; distinguish " gum," the fleshy covering of the base of a tooth, in O. Eng. gbma, palate, cf. Ger. Gaumen, roof of the mouth; the ultimate origin is probably the root gha, to open wide, seen in

gum known as Epulis . A Myoma is composed of unstriped muscle fibres . It is a rare tumour sometimes found in the See also:

• OESOPHAGUS (Gr. o'lvca=I will carry, and r/)ayeiv, to eat)

oesophagus, See also:

• STOMACH (Gr. vrbsaxos from arbga, a mouth)

stomach and See also:

• BLADDER (from A.S. blaeddre, connected with bl¢wan, to blow, cf. Ger. blase)

bladder . Osteoma (fig . 8).—Bony tumours not infrequently arise from the bones of the See also:

• HEAD (in 0. Eng. heafad; the word is common to Teutonic languages; cf. Dutch hoofd, Ger. Haupt, generally taken to be in origin connected with Lat. caput, Gr. KerbOvi7)
• HEAD, SIR EDMUND WALKER, BART
• HEAD, SIR FRANCIS BOND, BART

head or See also:

• FACE (from Lat. fades, derived either from facere, to make, or from a root fa-, meaning " appear "; cf. Gr. cbatvstv)

face . They grow very slowly, and are so hard that surgical removal may be very difficult . They also occur as irregular outgrowths from the bones of the limbs, and are then known as Exostoses (fig .

9) . A common site for these is the inner and See also:

• LOWER

lower end of the femur, at the point of See also:

• ATTACHMENT

attachment of the adductor muscle, and such a tumour seems to originate from an ossification of the tendon of this muscle . j FIG . 9.—Exostosis of the femur _ produced by the ossification of the FIG. so.—Multiple chondromata tendon of the adductor See also:

• MAGNUS, HEINRICH GUSTAV (1802-1870)

magnus. of the fingers . Chondroma (fig. lo).—Cartilaginous tumours are often found in See also:

• CHILDREN, LAW RELATING TO

children and. See also:

• YOUNG
• YOUNG, A
• YOUNG, ARTHUR (1741-1820)
• YOUNG, BRIGHAM (1801-1877)
• YOUNG, CHARLES MAYNE (1777–1856)
• YOUNG, EDWARD (1683–1765)
• YOUNG, JAMES (1811-1883)
• YOUNG, THOMAS (1773-1829)

young See also:

• PEOPLE

people growing from the bones of the limbs in the neighbourhood of the See also:

• JOINTS

joints . They are frequently multiple, especially in the hands and feet . These tumours grow slowly and are quite painless . Should removal be necessary, it is usually an easy matter . Odontoma.—Several varieties of this tumour have been described arising in connexion with the teeth and due to delayed or faulty development . They may cause great deformity of the jaw . A Myxoma is composed of loose, gelatinous connective tissue similar to that found in the umbilical See also:

• CORD (derived through the Fr. corde, from the Lat. chorda, Gr. xop(5rt, the string of a musical instrument)

cord . Some nasal polypi seem to be of this nature, but true myxomatous tumours are rare .

It is, however, not uncommon for a fibroma or a sarcoma to be converted by degeneration into myxomatous-like tissue . Neuroma.-A pure neuronia is very uncommon, but a tumour known as a Pseudo-neuroma (fig . II) is often found in the course of a nerve . This is formed by a localized overgrowth of the fibrous tissue of the nerve sheath . Glioma.—This variety of tumour arises from the neuroglia, the supporting tissue of the brain and See also:

• SPINAL

spinal cord . Consequently gliomata are only found in these two structures . Endothelioma.—Of See also:

• LATE

late years a small class of tumour has been described as originating apparently from the endothelium lining the lesser blood and lymph channels . Many of the recorded examples have been connected with the mouth, the tongue, the See also:

• PALATE (Lat. palatum, possibly from the root of pascere, to feed)

palate or the parotid gland . Some of these tumours are quite innocent, others are typically malignant . An Angesoma consists of a mesh-work of blood-vessels See also:

• BOUND, or BOUNDARY (from O. Fr. bonde, Med. Lat. bodena or butina, a frontier line)

bound together by a small amount of fat and fibrous tissue . Two varieties are described : (a) The simple See also:

• NAEVUS

naevus, or See also:

• PORT

port-See also:

• WINE (Lat. vinum, Gr. oivos)

wine stain, scarcely deserves to be called a tumour . It appears as a reddish-See also:

• BLUE (common in different forms to most European languages)

blue discolouration of the skin due to over growth and dilatation of the under-lying blood-vessels .

This condition is most commonly found on the face or See also:

• SCALP (0. Dutch schelpe, a shell)

scalp, and may be of congenital origin . (b) In the cavernous naevus the vascular hypertrophy is on a larger See also:

• SCALE
• SCALE (1) A

scale, and may produce a definite pulsating tumour . Here, again, the head is the usual situation . Sarcoma.—This is the malignant type of the connective-tissue tumour . The general arrangement of a sarcoma shows a mass of atypical cells loosely bound to- gether by a small amount of connective tissue . The cells vary greatly in size and shape in different tumours, and in accordance with the prevailing type the following varieties of sarcoma have been described: (i.) See also:

• ROUND (O. Fr. rond, Lat. rotundus, the Fr. is the source also of Du. rond; Ger., Swed., Dan. and Nor. rond)

round-cell sarcoma, (ii.) spindle-cell sarcoma, (iii.) See also:

• MELA, POMPONIUS (ft. c. A.D. 43)

mela- notic sarcoma, (iv.) myeloid sar- See also:

• COMA (Gr. K(.7)

coma . The first two groups contain the great majority of all sarcomata, and may occur in almost any part of the body, but they are especially liable to attack the bones (fig . Ta) . A sarcoma of bone may be either periosteal when it grows from the periosteum covering the See also:

• OUTER

outer See also:

• SURFACE

surface of the bone, or enrosteal when it' lies in the medullary cavity . A peculiar form of sarcoma is found in the parotid and other salivary glands . The cells are usually spindle - shaped, and among them lie scattered masses of cartilage and fibrous tissue . These tumours are seldom very malignant, and dissemination is rare (fig .

13) . The melanotic sarcoma is of a See also:

• BROWN
• BROWN, CHARLES BROCKDEN (1771-181o)
• BROWN, FORD MADOX (1821-1893)
• BROWN, FRANCIS (1849- )
• BROWN, GEORGE (1818-188o)
• BROWN, HENRY KIRKE (1814-1886)
• BROWN, JACOB (1775–1828)
• BROWN, JOHN (1715–1766)
• BROWN, JOHN (1722-1787)
• BROWN, JOHN (1735–1788)
• BROWN, JOHN (1784–1858)
• BROWN, JOHN (1800-1859)
• BROWN, JOHN (1810—1882)
• BROWN, JOHN GEORGE (1831— )
• BROWN, ROBERT (1773-1858)
• BROWN, SAMUEL MORISON (1817—1856)
• BROWN, SIR GEORGE (1790-1865)
• BROWN, SIR JOHN (1816-1896)
• BROWN, SIR WILLIAM, BART
• BROWN, THOMAS (1663-1704)
• BROWN, THOMAS (1778-1820)
• BROWN, THOMAS EDWARD (1830-1897)
• BROWN, WILLIAM LAURENCE (1755–1830)

brown or See also:

• BLACK
• BLACK, ADAM (1784-1874)
• BLACK, JEREMIAH SULLIVAN (1810–1883)
• BLACK, WILLIAM (1841-1898)

black See also:

• COLOUR (Lat. color, connected with celare, to hide, the root meaning, therefore, being that of a covering)

colour owing to the presence of granules of pigment (melanin) in and among the tumour cells . A melanotic sarcoma may arise from a pigmented See also:

• WART (Lat. verruca)

wart or See also:

• MOLE
• MOLE, LOUIS MATHIEU, COMTE (1781—1855)
• MOLE, MATHIEU (1584—1656)

mole, or throughout the body . The myeloid sarcoma, or myeloma (fig . 14), is composed of very large cells like those of bone-marrow from which it is probably derived . It is only found in the interior of bones, chiefly in those of the See also:

• ARM (a common Teutonic word; the Indo-European root is ar, to join or fit; cf. the Lat. armus, shoulder, and the plural word arma, weapons, Gr. apphs, joint, and the reduplicated apapilKSV, to join)

arm and See also:

• LEG
• LEG (a word of Scandinavian origin, from the Old Norwegian leggr, cf. Swed. lagg, Dan. laeg; the O. Eng. word was sceanca, shank)

leg . The degree of malignancy is See also:

• LOW, SETH (1850- )
• LOW, WILL HICOK (1853- )

low, dissemination never occurs, and recurrence after operation is rare . myeloma . II.—Epithelial Tumours . Papilloma.—The familiar example of a papilloma is the simple wart, which is formed by a proliferation of the squamous epithelium of the skin (fig . 3) . It seems probable that some warts are of an infective nature, for instances of direct contagion are not uncommon .

Occasionally warts are pigmented, and are then liable to be the seat of a melanotic sarcoma . Papillomata are also found in the bladder (fig . 15), as See also:

• LONG, GEORGE (1800-1879)
• LONG, JOHN DAVIS (1838– )

long delicate filaments growing from the bladder wall . These consist of a connective-tissue core covered by a thin layer of epithelium . Adenoma . — (Figs. la and lb) . The glandular tumours are of very common occurrence in the breast, the ovary and the intestinal See also:

• CANAL
• CANAL (from Lat. canalis, " channel " and " kennel " being doublets of the word)

canal . The structure of an adenoma of the breast has already been described (vide supra), and the structure of other adenomata is on the same general plan . The main features of an innocent. glandular tumour are: (a) the presence of a rounded, painless swelling with a well-defined margin; (b) the swelling is freely movable in the surrounding tissues, and if it lies close beneath the skin it is not attached thereto; (c) there is no enlargement of the neighbouring lymphatic glands . arcinoma.—The following varieties of carcinoma are described: i . Squamous-cell carcinoma (fig . 4), arising from those parts of the body covered by squamous epithelium, namely the skin, the mouth, the pharynx, the upper part of the oesophagus and the bladder .

ii . Spheroidal-cell carcinoma (figs. za and zb), arising from spheroidal epithelium, as in the breast, the pylorus, the See also:

• PANCREAS (Gr. rag, all; 1cpks, flesh)

pancreas, the kidney and the prostrate . iii . Columnar-cell carcinoma (figs . 16 and 17), arising from columnar epithelium, as in the intestine . The general histology of these tumours corresponds to that of a spheroidal-cell carcinoma already described (vide supra), the only variation between the three groups being in the shape of the cells . The clinical characteristics of a carcinoma, whatever its situation, are: (a) the presence of a swelling which has no well defined margin, but fades away into the surrounding tissues to which it is fixed; (b) when the tumour lies near the skin (e.g. a carcinoma r from the pigmented layers of the retina . The primary growth is usually small, but dissemination occurs with great rapidity sarcoma of fibula . of the breast) it becomes fixed to this at an early date; (c) the tumour is painful and See also:

• TENDER

tender, the degree of pain varies widely, d I r° (Redrawn from Ziegler's Pathological See also:

• ANATOMY
• ANATOMY (Gr. avaroyil, from ava-silo c', to cut up)

Anatomy, by permiss?on of See also:

• MACMILLAN

Macmillan & Co.) cancer of stomach . and in the early stages there may be none; (d) the neighbouring lymphatic glands soon become enlarged and tender, showing that they are the seat of metastatic deposits; (e) in squamous carcinoma of the skin, ulceration speedily occurs . Rodent Ulcer.—This shows itself as a slowly progressing ulceration of the skin, and is especially common on the face near the eye or See also:

• EAR (common Teut.; O.E. are, Ger. Ohr, Du. oor, akin to Lat. auris, Gr. ovs)

ear . The condition is one of purely See also:

• LOCAL

local malignancy, and. dissemination does not occur .

It is believed to be a carcinoma of the sebaceous glands of the skin . (L .