Leiomyoma (leiomyoma; from Greek. Leios - smooth and mys, myos - muscle) - is a benign tumor originating from smooth muscle fibers.
Leiomyomas can occur in all organs where smooth muscle fibers are present, but are more common in the uterus, in the digestive tract, bladder, prostate gland and skin. By origin, the leiomyoma of the skin, esophagus, intestine is considered as a dysontogenetic formation, the uterine leiomyoma - as a consequence of endocrine disorders.
The tumor is round, clearly delimited from the surrounding tissues; its consistency is dense, especially with a high content of connective tissue (leiomyofibroma). Leiomyoma nodes are often multiple, sizes vary from microscopic to the diameter of the head of a full-term fetus and more; on the section - pinkish, gray-white color with a peculiar layered pattern due to the intersection of differently located muscle bundles. Microscopically, leiomyoma is made up of muscle fibers, which are somewhat larger than normal fibers. The nuclei of tumor cells are also relatively larger and richer in chromatin. In the leiomyoma, the muscle fibers form randomly arranged bundles, and around the vessels they are sometimes placed concentrically, in the form of couplings. Vessels are usually few; they are thin-walled, with a narrow gap; rarely, leiomyomas contain a large number of dilated vessels (cavernous leiomyoma).Go
In long-existing leiomyomas, dystrophic and atrophic changes in muscle fibers can be observed as a result of circulatory disorders, replacing them with connective tissue; the latter may undergo hyalinosis, petrification, less ossification. In addition, in leiomyomas foci of necrosis, hemorrhage with the formation of cysts can occur. The malignancy of a leiomyoma is possible (see. Leiomyosarcoma). Surgical treatment, the prognosis is favorable.
Skin leiomyoma (synonym: myoma cutis, dermatomyoma) is usually a benign tumor of the skin, originating from smooth muscle tissue. There are single leiomyomas of the skin, single leiomyomas of the genital organs (these leiomyomas have some structural features) and multiple leiomyomas of the skin. Histologically, all skin leiomyomas are characterized by interlacing bundles of smooth muscle fibers with bundles of collagen tissue.
Single leiomyomas of the skin (synonym for single angioleiomyomas) are formed from the smooth muscles of the venous wall, are nodes that do not usually exceed 1 cm, less often 1.5 cm in diameter. Located in the thickness of the dermis, protrude above the surrounding skin in the form of oval or rounded tumors of a pinkish-yellow color, sometimes with a brown tinge. Borders are clear (tumors are encapsulated), the consistency is dense. Often, tumors are permeated with blood vessels. On the skin of the face and limbs, often the upper, there may be groups of mobile tumors that are not interconnected. On palpation there is a sharp pain, but it can occur spontaneously. Hot flashes develop suddenly and also suddenly disappear in 1.5-2 hours. The pain and "tension" of the tumor can intensify under the influence of cold.
Single leiomyomas of the genital organs can develop on the scrotum, labia, in the nipple area of the mammary glands. These tumors are pinkish-yellow in color, up to the size of a hazelnut, usually unstressed.
Multiple leiomyomas of the skin - no more than 0.5–0.7 cm in diameter, often strained, can be located disseminated and in groups, often combined with uterine fibroids. Cases of the disease of several family members are described, as well as the development of multiple skin leiomyomas at the site of injury.
Single genital leiomyomas and multiple skin leiomyomas are not encapsulated; the number of blood vessels in them is small, the amount of collagen is usually very significant; are located in the dermis.
The course of skin leiomyoma is long, the prognosis is favorable, malignant degeneration is extremely rare. Treatment: surgical, electrocoagulation, the use of carbonic snow.