From Big Medical Encyclopedia

HISTIOCYTOMA (histiocytoma; Greek histion a sail, fabric + kytos a vessel, a cell + - oma; synonym: gistiotsitoksantoma, xanthofibroma, histiocytoma of skin, nevoksantoendoteliom) — benign tumor of a connective tissue origin. It is quite often described together with angiofibromas, to the Crimea this tumor, apparently, is close.

the Microscopic structure of the histiocytoma (a) located in a derma: 1 — atrofichny epidermis; 2 — Tuton's cells; 3 — cells of a tumor; — Tuton's cell at bigger increase.

Macroscopically G. represents the dense, painless node towering over skin (to dia, to 1 — 2 cm), on a section of pinkish-yellowish color. Microscopically under atrofichny epidermis the tumor which is indistinctly delimited from surrounding fabric consisting of a set of cells of various form and the sizes is defined. Small cells meet dark kernels and very scanty basphilic cytoplasm, cells of type epithelioid the foamy cytoplasm containing fat (usually birefringent) and a set of colossal cells of Tuton (fig). These are very large cells with the numerous kernels which are located in the form of a ring or a half ring around the basphilic site of cytoplasm in the center of a cell. The peripheral department of cytoplasm light, a foamy look, contains birefringent lipids. Also accumulations of typical ksantomny cells, a significant amount of vessels of capillary type and gentle friable fibrous fabric, here and there with existence of the rhythmical structures close to moire are found. G.'s fibrosing is considerable less than angiofibromas (see), the tumor contains few haemo siderophages and differs in it from an angiofibroksantoma a little. Grows slowly. It Malignizirutsya exclusively seldom.

The tumor is usually solitary, but sometimes happens multiple, occurs equally often at men and women. Unlike an angiofibroma, the cut is favourite localization skin of the lower extremities, G. is located preferential on head skin, especially on a face, but can appear on any other body part. Quite often develops at children and young men, but sometimes arises also at advanced age. The etiology is unknown. Treatment — excision; as a rule, a recurrence does not arise. Forecast favorable.

See also Tumours .

Bibliography: Niyemi K. M. Benign fibrogistiotsitarny tumors of skin, the lane with English, M., 1973, bibliogr.; The guide to pathoanatomical diagnosis of tumors of the person, under the editorship of N. A. Krayevsky and A. V. Smolyannikov, page 89, M., 1976, bibliogr.; Smolyan-nikov A. V. Morphological diagnosis of tumors of soft tissues, M., 1969, bibliogr.

A. A. Kdimenkov.