Polyps

POLYPS (polypus), growths sitting on one surface or another and connected to the latter by a stalk of varying thickness. A polyp is a broadly morphological concept, under which formations of the most diverse character may be implied. Thus, for example, cardiac polyps are what are called parietal thrombi of the atrial appendages and heart ventricles, in view of the fact that these thrombi, being connected to the inner surface of the heart (between the trabeculae), protrude into the cavity of the heart in the form of spherical formations. By placental polyps, one understands an organizing necrotic mass protruding on a broad base into the uterine cavity and representing a retained and dead part of the placenta. The term hair polyp (German: Haarpolyp) is applied to a teratoma covered with hair, sometimes encountered in the nasal cavity, pharynx, or mouth, and hanging in the form of a pear-shaped formation on the mucosa. The most typical polyps are those that form on mucous membranes and consist, as it were, of the tissue of the mucous membrane itself. However, these true polyps of mucous membranes can in turn be formations that are different in their essence. The greater part of them relates to limited hyperplasias of the mucosa of inflammatory origin; in other cases, a polyp of the mucosa may represent a true neoplasm of the mucosa and its glands, a polypous adenoma; finally, some polyps are a peculiar manifestation of a developmental defect of the mucosa. Furthermore, tumors of the wall of one cavity or tube or another can take on a polypous appearance if they, by lifting the mucosa, hang into the lumen of the cavity (e.g., polypous fibromas, myxomas, lipomas of the nose, larynx, intestines). By their macroscopic appearance, polyps of mucous membranes can appear as limited bulges sitting on a broad base and having the appearance of folds of the mucosa, or they have the shape of a mushroom (fungous polyp), or finally, the polyp represents a pear-shaped body connected to the mucosa by a thin stalk. Sometimes polyps are observed with the formation of papillae on the surface (papillomatous polyps). The sizes of polyps can be different: from the size of a millet seed to a large pear and larger; however, ordinary inflammatory polyps of mucous membranes rarely reach large sizes. By their histological structure, a polyp is often built in the same way as the given mucous membrane, i.e., its base is formed by proliferated submucosal tissue, and the surface is covered with an epithelial covering with glands corresponding to the given mucous membrane (simple mucous polyps, p. mucosus). In some of these polyps, the connective tissue base turns into mucous tissue, in connection with which the polyp becomes soft and translucent; such polyps are called myxomatous polyps (p. myxomatosus, see Myxoma). Sometimes in a polyp there is a significant development of blood vessels of the venous type, which is the reason for calling such polyps, which usually bleed heavily, vascular or angiomatous polyps (p. vasculosus, angiomatosus). Those polyps in which a proliferation of glands is microscopically detected border on adenomas and are called adenomatous polyps (p. adenomatosus). If in a polyp one or several glandular cavities are strongly dilated by secretion, then one speaks of a cystic polyp. The places where the aforementioned polyps most often develop are the mucous membranes of the nose, larynx, uterus, stomach, and intestines. The number of polyps in individual cases is different: in the nose, larynx, and uterus, the development of solitary polyps is more often observed, or the formation of a group of polyps in a limited place takes place, which gives a picture of local polypous proliferation of the mucosa. In the stomach and intestine, especially in the large intestine, besides individual polyps, multiple polyps are often encountered, which is called polyposis of the stomach or intestines. In the intestine, these multiple polyps, sometimes dotting the mucosa in a huge quantity throughout the entire extent from the exit of the stomach to the anal opening, usually have an adenomatous character (polyposis adenomatosa intestinalis); the circumstance that such multiple adenomatous polyposis is sometimes encountered in childhood forces one to think about the congenital basis of this affliction; Borst classifies these polyps as hamartomas (see). Polyps of different types often ulcerate; very often inflammatory changes are observed in them, and as a consequence of circulatory disturbance—hemorrhages, edema, etc. Twisting and compression of the polyp stalk can lead to its necrosis, sometimes resulting in the spontaneous detachment of the polyp. Adenomatous polyps of the stomach, intestines, and uterus often transform into glandular cancer. The significance of polyps is very diverse. Some polyps, for example of the stomach or intestines, do not cause any disturbances and are very often discovered at autopsy as an incidental finding. In other cases, polyps bleed or maintain an inflammatory state of the given area; sometimes they narrow or close the corresponding passages, for example in the nose—the nasal passages, choanae; in the stomach—the exit orifice; in the intestine—its lumen [see separate plate (cols. 23-24), figs. 1 and 2]. In some cases, a large polyp can strongly pull the wall of a cavity, which, for example, in the intestine can result in intussusception of the intestines or, in the rectum, its prolapse. The treatment of polyps is surgical.