Manual of Surgery Volume First: General Surgery. Sixth Edition.

by Alexis Thomson; Alexander Miles

Papilloma.—A papilloma is a tumour which projects from a cutaneous or mucous surface, and consists of a central axis of vascular fibrous tissue with a covering of epithelium resembling that of the surface from which the tumour grows. In the papillomas of the skin—commonly known as warts—the covering consists of epidermis; in those growing from mucous surfaces it consists of the epithelium covering the mucous membrane. When the surface epithelium projects as filiform processes, the tumour is called a villous papilloma, the best-known example of which is met with in the urinary bladder. Papillomatous growths are also met with in the larynx, in the ducts of the breast, and in the interior of certain cystic tumours of the breast and of the ovary. Although papillomas are primarily innocent, they may become the starting-point of cancer, especially in persons past middle life and if the papilloma has been subjected to irritation and has ulcerated. The clinical features and treatment of the various forms of papilloma are considered with the individual tissues and organs.

Adenoma.—An adenoma is a tumour constructed on the type of, and growing in connection with, a secreting gland. In the substance of such glands as the mamma, parotid, thyreoid, and prostate, adenomas are met with as encapsulated tumours. When they originate from the glands of the skin or of a mucous membrane, they tend to project from the surface, and form pedunculated tumours or polypi.

Adenomas may be single or multiple, and they vary greatly in size. The tumour is seldom composed entirely of gland tissue; it usually contains a considerable proportion of fibrous tissue, and is then called a fibro-adenoma. When it contains myxomatous tissue it is called a myxo-adenoma, and when the gland spaces of the tumour become distended with accumulated secretion, a cystic adenoma, the best examples of which are met with in the mamma and ovary. A characteristic feature of the cystic variety is the tendency the tumour tissue exhibits to project into the interior of the cysts, constituting what are known as intracystic growths. They are essentially innocent, but intracystic growths, especially in the mamma of women over fifty, should be regarded with suspicion and therefore should be removed on radical lines. Transition forms between adenoma and carcinoma are also met with in the rectum and large intestine, and these should be treated on the same lines as cancer.

Carcinoma or Cancer

A cancer is a malignant tumour which originates in epithelium. The cancer cells are derived by proliferation from already existing epithelium, and they invade the sub-epithelial connective tissue in the form of simple or branching columns. These columns are enclosed in spaces—termed alveoli—which are probably dilated lymph spaces, and which communicate freely with the lymph vessels. The cells composing the columns and filling the alveoli vary with the character of the epithelium in which the cancer originates. The malignancy of cancer depends on the tendency which the epithelium has of invading the tissues in its neighbourhood, and on the capacity of the cells, when transported elsewhere by the lymph or blood-stream, of giving rise to secondary growths.

Cancer may arise on any surface covered by epithelium or in any of the secreting glands of the body, but it is much more common in some situations than in others. It is frequently met with, for example, in the skin, in the stomach and large intestine, in the breast, the uterus, and the external genitals; less frequently in the gall-bladder, larynx, thyreoid, prostate, and urinary bladder.

Tissues appear to be most liable to cancer when, having attained maturity, they enter upon the phase of decadence or involution, and this phase is reached by different tissues at different periods. It is not so much, therefore, the age of the person in whom it occurs, as the age of the tissue in which it arises, that determines the maximum incidence of cancer. Cancer of the stomach appears and attains a maximum frequency earlier than cancer of the skin; cancer of the uterus and mamma is more frequent towards the decline of reproductive activity than in the later years of life; rectal cancer is not infrequently met with during the second and third decades. There is evidence that the irritation caused by alcohol and tobacco plays a part in the causation of cancer, in the fact that a large proportion of those who become the subjects of cancer of the mouth are excessive drinkers and smokers.

A cancer may appear as a papillary growth on a mucous or a skin surface, as a nodule in the substance of an organ, or as a diffuse thickening of a tubular organ such as the stomach or intestine. The absence of definition in cancerous tumours explains the difficulty of completely removing them by surgical measures, and has led to the practice of complete extirpation of cancerous organs wherever this is possible. The boundaries of the affected organ, moreover, are frequently transgressed by the disease, and the epithelial infiltration implicates the surrounding parts. In cancer of the breast, for example, the disease often extends to the adjacent skin, fat, and muscle; in cancer of the lip or tongue, to the mandible; in cancer of the uterus or intestine, to the investing peritoneum.

In addition to its tendency to infiltrate adjacent tissues and organs, cancer is also liable to give rise to secondary growths. These are most often met with in the nearest lymph glands; those in the neck, for example, becoming infected from cancer of the lip, tongue, or throat; those in the axilla, from cancer of the breast; those along the curvatures of the stomach, from cancer of the pylorus; and those in the groin, from cancer of the external genitals. In lymph vessels the cancer cells may merely accumulate so as to fill the lumen and form indurated cords, or they may proliferate and give rise to secondary nodules along the course of the vessels. When the lymphatic network in the skin is diffusely infected, the appearance is either that of a multitude of secondary nodules or of a diffuse thickening, so that the skin comes to resemble coarse leather. On the wall of the chest this condition is known as cancer en cuirasse. Although the cancer cells constantly attack the walls of the adjacent veins and spread into their interior at a comparatively early period, secondary growths due to dissemination by the blood-stream rarely show themselves clinically until late in the course of the disease. It is probable that many of the cancer cells which are carried away in the blood or lymph stream undergo necrosis and fail to give rise to secondary growths. Secondary growths present a faithful reproduction of the structure of the primary tumour. Apart from the lymph glands, the chief seats of secondary growths are the liver, lungs, serous membranes, and bone marrow.

It is generally believed that the secondary growths in cancer that develop at a distance from the primary tumour, those, for example, in the medullary canal of the femur or in the diploë of the skull occurring in advanced cases of cancer of the breast, are the result of dissemination of cancer cells by way of the blood-stream and are to be regarded as emboli. Sampson Handley disagrees with this view; he believes that the dissemination is accomplished in a more subtle way, namely, by the actual growth of cancer cells along the finer vessels of the lymph plexuses that ramify in the deep fascia, a method of spread which he calls permeation. It is maintained also that permeation occurs as readily against the lymph stream as with it. He compares the spread of cancer to that of an invisible annular ringworm. The growing edge extends in a wider and wider circle, within which a healing process may occur, so that the area of permeation is a ring, rather than a disc. Healing occurs by a process of “peri-lymphatic fibrosis,” but as the natural process of healing may fail at isolated points, nodules of cancer appear, which, although apparently separate from the primary growth, have developed in continuity with it, peri-lymphatic fibrosis having destroyed the cancer chain connecting the nodule with the primary growth. This centrifugal spread of cancer is clearly seen in the distribution of the subcutaneous secondary nodules so frequently met with in the late stages of mammary cancer. The area within which the secondary nodules occur is a circle of continually increasing diameter with the primary growth in the centre.