GEMANGIOPERITSITOMA (haemangiopericytoma; grech, haima blood + angeion a vessel + peri-near, near + kytos a vessel, a cell + - oma) — the vascular tumor formed by a set of the capillaries surrounded with spindle-shaped and round cells — pericytes.
The term «Gemangioperitsitoma» is offered by Stout and Mari (And. P. Stout, M. R. Murray). There is an opinion that G. of a gistogeneticheska is connected with the hemoretseptorny device, i.e. belongs to neuroectodermal tumors of type paragangliomas (see). Distinguish differentiated and undifferentiated.
The differentiated G. meets seldom, can arise at any age, is frequent at children. As a rule, it is characterized by slow growth, usually reaches the large sizes, keeping at the same time accurate contours and mobility. It is localized preferential in skin, soft tissues of a trunk and extremities, is more rare — in retroperitoneal space, a mediastinum, an epiploon, language and internals (a liver, intestines, a brain, etc.)*. A macroscopic structure — a tumor of a knotty form, on the section of pinkish-red color, a porous structure, with abundance suitable it vessels. It is microscopically characterized by a large number of the capillaries covered by an endothelium and surrounded with roundish, oval or spindle-shaped cells with dark kernels and light cytoplasm (fig. 1). Cells are braided by dense network of argyrophil fibers. The main difference of G. from a capillary angioma is massive proliferation of perivascular cells most of which of researchers carries to pericytes.
Differentiated.are, as a rule, delimited from soft tissues by a layer of the hyalinized fabric, edges, however, on many sites it is couched by tumor cells that demonstrates mestnodestruiruyushchy growth. The differentiated G. are potentially malignant tumors since have high tendency to a recurrence after insufficiently broad surgical excision. In rare instances of differential
Undifferentiated. (synonym: gemangioperitsitarny sarcoma, peritelialny sarcoma, a perithelioma, a periendothelioma) is a malignant tumor. At an early stage of development undifferentiated G. clinically and even on the basis morfol, researches it is difficult to distinguish from differentiated. The tumor meets seldom, is localized preferential in soft tissues of extremities, is more rare in retroperitoneal cellulose, internals, bones. In most cases the undifferentiated G. which are localized in soft tissues keep accurate contours and only in late stages skin, bones, sosudistonervny educations are surprised. At microscopic examination polymorphism of cells is observed; among cells spindle-shaped forms prevail, the abundance of figures of division (fig. 2), germination of cells in a gleam of vessels, infiltration of surrounding fabrics is observed. Differs in aggressive growth, often metastasizes (up to 15% in regional limf, nodes and to 50% in lungs) and recurs (in 40 — 50% of cases).
Treatment both forms surgical, the forecast adverse — after treatment apprx. 50% of patients live up to 5 years and only 20% — up to 10 years.
Bibliography: Klimenkov A. A. The long-term results of treatment of malignant tumors of soft tissues, in book: Tumors of a musculoskeletal system, under the editorship of H. N. Trapeznikova, century 3, page 43, M., 1971; P e r e with l of e of and I. A. N and d river. Radiation therapy gemangioperitsity, Medical radio-gramophones., t. 13, JVe 1, page 15, 1968; The Guide to pathoanatomical diagnosis of tumors of the person, under the editorship of N. A. Krayevsky and A. V. Smolyanniko-va, page 68, M., 1971. And _ „
A. A. Klimenkov.