The pathology of tubercular ulceration of the rectum is graphically described in Ziemssen's Encyclopædia as follows: "These [ulcerations] begin in the follicular apparatus with swelling of the individual follicles and their vicinity from tuberculous deposit. The newly-formed cells become caseous, the superficial layer of the tubercle breaks down, and thus ulcerations arise of a round funnel shape. The enlargement of these ulcerations is probably produced by the constant formation in the base and edges of the ulcers of new nodules, which themselves caseate and ulcerate. This process of extension, to which these tuberculous ulcerations of the intestines exhibit a marked tendency, takes place chiefly in a transverse direction (girdle-shape), following the direction of the blood-vessels. The infiltration and necrosis may advance longitudinally, and, finally, the individual ulcerations coalesce with each other: in this way may be explained in part the dentate appearance of the edges of these ulcerations. The ulceration extends also in depth, although usually the muscular coat appears to be covered by a thick layer of connective tissue: the destruction advances slowly in the muscularis, but in the lymphatic vessels which pierce the muscularis less opposition is presented to the progress of the tuberculosis; and thus it is not uncommon to find tubercles ranged one after the other, like links in a chain, from the base of the ulcer directly down to the serosa. Healing is extremely rare. The most frequent situation is the lower end of the ileum, but the process may extend upward to the stomach, or downward, involving the rectum. There is almost invariably unmistakable signs of tuberculosis in other organs. It is possibly never primary, but this is a still-disputed point. It usually occurs with tuberculosis of the lungs, and when so occurring it is always secondary. The clinical symptoms of this state are by no means characteristic."
Dwelling upon the subject of intestinal tubercle, it has been suggested by Klebs18 that the intestinal disease is produced by swallowing morbid products derived from phthisical lungs—an hypothesis supported also by the fact that tubercle in the intestines tends so strongly to spread downward. "The seat of the deposit is the submucous tissue or the corium of the mucous membrane: it is certainly subjacent to the basement membrane, and not contained in the follicles, as Creswell taught."
18 Jones and Sieveking, London, pp. 593-595.
Woodward, in his article upon diarrhoea,19 says: "The lesions, whether mild or severe, are most generally seated in the cæcum and colon, but more or less extensive tracts of the small intestine, especially of the ileum, are often involved also." He continues: "Tubercular disease of the lung was noted in nearly one-sixth of the autopsies of fatal cases of forms of flux heretofore described. Possibly the frequency in chronic cases may be explained by the fact that protracted intestinal flux forms the development of lung phthisis in the predisposed."
19 Med. and Surg. History of the War of the Rebellion, p. 266.
The rectal fissure or painful ulcer may be connected with diathetic causes, as struma or scrofula: it is doubtful if syphilis should be included among its causes.
Cancer, Malignant Stricture, and Malignant Ulceration.
The forms of cancer met with in these regions are epitheliomatous, scirrhous, encephaloid, and colloid. Considerable diversity of opinion has existed as to which variety occurs most frequently; but it is now probably a matter of absolute knowledge that the epithelial form is the one most commonly observed, and next to that in frequency the scirrhous form. Encephaloid and colloid are of quite infrequent occurrence. Again, as to the sex in which this affection appears the most often, there is much disparity existing between surgical writers: it is usually thought to be much more prevalent among women than among men. This is not the experience of many of the authorities upon this subject, yet the statistics of the Hôtel Dieu, Paris, furnish overwhelming evidence in favor of its preponderance in women. Carcinoma of the rectum, occurring as a primary infiltration in the rectum, probably occurs oftener in men, but there are among females so many contiguous structures prone to cancerous degenerations, as the uterus, the vagina, the ovaries, the Fallopian tubes, tumors and cancerous masses occupying Douglas's cul-de-sac, that it would seem likely that they would be more frequently the victims of secondary cancerous deposit in the bowel or of erosion and extension of disease by contiguity or continuity. Epithelioma in other situations attacks men much more frequently than women. This form of disease usually occurs in middle life and in old age, but to this general rule there have been many exceptions; it has been seen in children. Allingham quotes its occurrence in a lad of seventeen, and Gowland in one of thirteen. It very rarely occurs as a secondary deposit of cancer in a remote region or organ. In the table of 4000 cases of rectal and anal disease, before referred to, cancer existed in 105. This disease is usually within easy reach of the finger, except when the growth is in the sigmoid flexure, being within an inch or two of the anus or from two and a half to three inches above it. The epithelial form, when it commences at the anus, is closely analogous to epithelioma of the lip: from the anal outlet it spreads upward into the bowel, or it may be primarily seated there. When occupying the junction of skin with mucous membrane it is sometimes sluggish, and a long time may elapse before it takes on aggressive action: induration, nodulation, obstinate fissure, or fungous growth marks its inception; as the condition proceeds, infiltration of surrounding structures takes place and large, hard, irregular masses form, which ulcerate, split, and form cauliflower excrescences. The rectum becomes blocked with fungoid growths: both these and the cancer proper are very vascular, and frequent hemorrhages occur, and an offensive muco-purulent discharge constantly oozes from the bowel.
Scirrhus of the rectum commences as an infiltration of the submucosa, which rapidly involves the other elements of the bowel, pushing hard nodules upward into the lumen of the intestinal tube: these break down and form ragged ulcers with indurated margins, and bleed profusely. Its situation is usually not higher than three inches above the anus. It has a tendency to invade all the neighboring organs and soft structures, to bind them to itself in a firm, dense mass, and to form communications with the vagina, bladder, uterus, perineum, and penis. Abscesses and fistulæ are common complications.
These neoplasms are insidious in their onset, and when seated at some little distance from the anus do not excite much pain at first. In the epithelial form the anus presents an abnormal appearance: it is inflamed and is covered with irritated, hypertrophied tags of integument bathed in a sanious, offensive fluid. Difficult defecation, of which the natural form is absent, with inordinate tenesmus, a sense of weight and fulness in the bowel, and an irritable condition of the bladder, are among the symptoms. The feces are passed in little, irregular lumps or broken fragments, or this state is accompanied by or alternates with small, liquid, offensive stools. As the diseased action proceeds, very severe local and general pain is endured: this is of a dull, lancinating character, and affects not only the diseased bowel, but involves the entire contents of the pelvis, shoots down the thighs, up the back, and into the penis: frequent and exhausting hemorrhages take place; the patient exhales a peculiar sickening odor; his complexion becomes cachectic; his strength fails; and death ensues, after a variable period of intense suffering, from a few months to two or three years after the first symptoms appeared. The modes of termination of life in these cases are—exhaustion, secondary deposition, septicæmia, peritonitis, and hemorrhage. Stricture of the bowel and very extensive ulceration attend all of these advanced cases of malignant rectal disease.