An encapsulated lipoma when thoroughly removed will not return.
Mixed forms of fibrous and fatty neoplasm are occasionally seen, and are referred to as lipoma fibromatosum or fibroma lipomatosum, according as one or the other tissue predominates. These growths are innocent in their character, but call for thorough extirpation. They frequently give rise to considerable discomfort or pain, and are called lipoma dolorosa.
Fibroma.
—Fibromas are tumors composed of fibrous tissue, which, when of pure type, are found to be not so common as was formerly supposed, the majority of tumors hitherto roughly grouped as fibromas containing either muscle tissue or sarcomatous elements, which takes them out of the category of pure fibroma. A typical fibroma is ordinarily dense, and is composed of wavy bundles of fibrous tissue whose cells are long and slender and closely packed together, the mass being permeated by distinct bloodvessels.
Fibroma occurs most commonly in the ovary, the uterus, the intestine, the gum (epulis), in nerve sheaths, and in the skin in the form of so-called painful subcutaneous tubercles and molluscum fibrosum. There is also a fibrous tumor of the skin, known as keloid, sustaining to fibroma the same relation that exists between exostosis and osteoma.
Painful subcutaneous tubercle is a sample of pure fibroma in the shape of a small, flattened, pea-like tumor which never attains great size. It is situated loosely in the subcutaneous structure and may form a visible prominence. Insignificant as it would thus appear, it becomes the seat of exasperating pain, particularly when touched or handled, which may radiate to considerable distances. The etiology of these growths is unknown.
In the ovary, the uterus, the intestine, and the larynx true fibrous tumors are pathological curiosities rather than common lesions.
Fig. 74
Keloid of external ear: a, dense tissue of skin; b, fibrous connective tissue; c, epidermis. (Klebs.)