From Big Medical Encyclopedia

TERATOMA (Greek teras, terat[os] the freak, ugliness + - oma; synonym: withpseudoneoplasm, an embrioma, the mixed teratogenic tumor, a tridermoma, a monodermoma, the parasitizing fruit) — the tumor consisting of fabrics of several types derivative of one, two or three germinal leaves presence to-rykh is not peculiar to those bodies and anatomic areas of an organism, in to-rykh the tumor develops.

There is a large number of hypotheses of an origin of T. On modern representations, T. treats group of germinogenny tumors. Germinogenny tumors develop from polipotentny (the development of any body tissues which is a source), highly specialized germinogenny epithelium of gonads capable to be exposed to a somatic and trophoblastic differentiation and to be a gistogenetichesky source of tumors, various on a structure, napr, seminomas (see) a small egg, dysgermoinomas (see) an ovary, embryonal cancer (see), horionepitelioma (see. Trophoblastic disease ), poliembrioma, teratomas, and also tumors combining structures of these new growths (a tumor more than one gistol. type). T., as well as other germinogenny tumors, it can initially be localized in testicles (see) and ovaries (see), and also to be located ekstragonadno (in presakralny area, retroperitoneal space, a mediastinum, in vascular textures of cerebral cavities, in the field of an epiphysis, in a nasal cavity and jaws). Ekstragonadnye T. develop also from a germinogenny epithelium. Developing of a tumor out of gonads is explained by a delay of a germinogenny epithelium a way of its migration from a wall of a vitellicle to the place of laying of gonads on 4 — 5 weeks of embryonic development.

In favor of the germinogenny nature of T. their most frequent localization in gonads, an arrangement of ekstragonadny T testifies. preferential along the central axis of a body on the way of migration of a germinogenny epithelium during pre-natal development, experimental data about the beginning of growth of T. within tubules of a small egg, cytogenetic data on an origin of T. from diploid germinogenny cells, similarity of ultrastructure of tumor cells and a germinogenny epithelium at experimental animals. Microscopic structure of germinogenny tumors, including and teratomas of various localizations, the same. Morphogenesis of T. also the hl is studied a little. obr. in an experiment.

On gistol. to a structure distinguish a mature teratoma, an unripe teratoma, a teratoma with malignant transformation.

The mature teratoma consists of several mature, well differentiated fabrics derivative of one, two or three germinal leaves (see). Mature T. can be a solid and cystous structure. Mature T. a solid structure (a solid teratoma of adult type, a high-quality teratoma) represents a tumor of various sizes with a smooth chicken skin. On a section it has an appearance uneven, dense, places of the tyazhisty, whitish-gray fabric containing the centers of cartilaginous and bone density, small cysts filled with transparent liquid or slime.

Mature T. a cystous structure — tumoral education, as a rule, the big sizes, with a smooth surface. On a section it is visible that the tumor is formed by one or several cysts filled with muddy gray-yellow liquid, slime or kashitseobrazny, grease contents. In a gleam of cysts there can be hair, teeth, fragments of a cartilage.

Morphologically mature T. a solid and cystous structure significantly do not differ from each other. They consist of fibrous connecting fabric, in a cut sites of well differentiated mature multilayer flat epithelium, an epithelium of intestinal and respiratory type creating organoid structures randomly alternate. Quite often fabric of peripheral nerves, apocrenic glands, bones, a cartilage, teeth, tissue of a brain and cerebellum, a fatty tissue, unstriated muscles meets. Less often in a tumor it is possible to find fabric of a sialaden, pancreas, adrenal gland, kidney, lung, mammary gland. Vast majority of mature T. a cystous structure are dermoid cysts (see. Dermoid ). Dermoid cysts are covered by a multilayer flat keratosic epithelium; in the thickness of a wall of a cyst, unlike an epidermoid cyst (see), there are appendages of skin — sweat and sebaceous glands, follicles of hair. Besides, in a wall of a dermoid cyst and in connecting fabric between cysts fragments and other mature fabrics which are listed above can be found.

Mature T. is a benign tumor and, as a rule, does not give metastasises though there are single messages on implantation of a tumor on a peritoneum at a rupture of T. ovary.

An unripe teratoma — the tumor consisting of unripe fabrics, the derivative all three germinal leaves reminding fabrics of an embryo in the period of an organogenesis. Macroscopically unripe T., as a rule, happens a solid or solidnokistozny structure. The sizes of a tumor vary over a wide range. It has uneven tes-tovatuyu a consistence, serovatobely color, on a section with small cysts and sites of sliming.

Microscopically in a tumor the centers of proliferation of an unripe intestinal, respiratory, multilayer flat epithelium, unripe cross-striped muscles, a cartilage which are located among unripe, friable, with places of myxomatous mesenchymal fabric are defined. Presence at unripe T is very characteristic. fabrics of a neurogenic and ectodermal origin (the neurogenic epithelium creating sockets of a glia, sites corresponding to a neuroblastoma, a ganglioneuroma, the structures reminding an eye of an embryo). Sites of fabric of a mature teratoma occur among unripe elements of embryonal type.

In a crust, time is not present a certain opinion on degree of a zlokachestvennost of unripe T., there are no accurate proofs that unripe fabrics of embryonal type are capable to to innidiation (see). In the International histologic classification of tumors of testicles and ovaries there are no instructions on the fact that unripe T. is a malignant analog of T. Obshcheprinyato that unripe T. represents potentially malignant tumor. Only those mature and unripe T possess symptoms of the real malignant tumor., to-rye are combined with embryonal cancer, a tumor of a vitellicle, a seminoma (dysgermoinoma) or horionepiteliomy. Depending on morfol. features of the second component a tumor call a teratoma with embryonal cancer, a teratoma with a seminoma or a teratoma with horionepiteliomy. Metastasize T. such structure in the lymphogenous and hematogenous way. The structure of metastasises can correspond to primary node or in them one of its components prevails.

The centers of a malignant germino-gene tumor in mature and unripe T. even at their small volume substantially define the forecast of a disease. In this regard necessary condition correct morfol. diagnoses the research of perhaps bigger number of pieces from different sites of a tumoral node is. Most likely, it is possible to explain with not care of a research of primary tumor that, according to many researchers, metastasises at obviously high-quality mature T. are defined at 30% of patients, and at unripe T. more than 2 years there live only 28% of the diseased. Essential help in differential diagnosis of mature and unripe T. and their combinations to malignant germinogenny tumors reaction can render It is Abelian — Tatarinova on alpha-fetoprotein (at a combination to different types of embryonal cancer) and definition of a caption of a chorionic gonadotrophin (see) — at a combination to horionepiteliomy.

A teratoma with malignant transformation — extremely rare form of a tumor. Its feature consists in emergence in T. malignant tumor of so-called adult type, such as planocellular cancer, adenocarcinoma or melanoma. E.g., cases of the planocellular cancer which developed in a dermoid cyst are described.

Rare kinds of T. so-called monodermalny highly specialized T. K are it the struma of an ovary, carcinoid of an ovary, a combination of these two tumors, etc. belong. The struma of an ovary is formed by tissue of a thyroid gland of a usual structure and can be followed by a hyperthyroidism (see). In a struma of an ovary there can be adenocarcinomas similar on a structure to crayfish of a thyroid gland (see). At carcinoid of an ovary patients can have an expressed carcinoid syndrome (see. Carcinoid ).

Wedge, picture is defined by hl. obr. T. Sushchestvuyut's localization nek-ry sexual and age features of primary localization and wedge, currents of various forms T. So, mature T. a cystous structure (dermoid cysts) seldom meet in testicles and it is quite frequent in ovaries and make apprx. 20% of all tumors of this body at women in childbearing age. Unripe T. a solid and solid and cystous structure meet more often in testicles, than in ovaries. Men up to 20 years are ill preferential. At boys aged from 7 up to 13 years of T. make about 40% of all tumors of testicles. At children of T. various localization can be inborn; more often than at adults, their ekstragonadny forms meet. So, ekstragonadny T. are often noted at girls, it is preferential in sacrococcygeal area. From ekstragonadny forms T. the sacrococcygeal T is most often observed. The tumor has the rounded or irregular form, is located in the field of a tailbone or in a crotch. Sacrococcygeal T. can reach the big sizes and interfere with the normal birth of the child. At localization in a crotch sacrococcygeal T. sometimes leads to disturbance of the act of defecation and an urination. Differential diagnosis is carried out with spinal hernia (see. Spinal cord ).

T. mediastinums it is, as a rule, localized in a front mediastinum (see), kpered from a pericardium and the main vessels, in process of growth can press in this or that pleural cavity or in a postmediastinum. For a long time T. mediastinums can clinically not be shown and are found accidentally at rentgenol. research. On the roentgenograms executed in a direct projection, T. mediastinums it is characterized by existence of the semicircular or semi-oval blackout with accurate, equal contours adjoining a median shadow. Intensity of blackout increases in process of its increase in sizes. In a side projection blackout is defined in retrosternal space, directly behind a shadow of a breast; in this projection it has the rounded or oval shape. Existence in a tumor of inclusions of bone density (teeth, phalanxes) is the most typical. T. a cystous structure with calcification at the edges comes to light on the roentgenogram or the tomogram as the intensive ring-shaped shadow bordering a shadow of a tumor in the form of a shell. In some cases T. a cystous structure the horizontal level, a shadow of T is visible. is more intensive in the lower half and is less intensive in upper (Phemister's symptom). At suppuration of T. a cystous structure and formation of the fistulas opening on skin of a thorax, their configuration can be specified by means of a fistulografiya. Relationship of T. mediastinums best of all decide on surrounding bodies and fabrics at a pnevmomediastinografiya (see).

Retroperitoneal T. the hl meets. obr. at children of early age it is also quite often shown the same as a nefroblastoma (see. Vilmsa tumor ) or retroperitoneal neuroblastoma (see). Importance in diagnosis of retroperitoneal T. the angiography, and also a X-ray analysis in the conditions of a pneumoperitoneum has.

Treatment of mature and unripe T. operational. At T., combined with other malignant germino-gene tumors, and also at T. with malignant transformation apply complex treatment. It includes an operational oncotomy, use of antineoplastic means and radiation therapy.

The forecast is defined by option gistol. structures, primary localization of a tumor, timely and adequate treatment. At mature and unripe T. forecast favorable. However for patients from unripe T. dynamic observation is, as a rule, recommended. The forecast at T., combined with embryonal cancer and horionepiteliomy, the most adverse. Is more good-quality the T proceeds., combined with a seminoma.

See also Tumours , Cancer .

Bibliography: Durnov L. A. Tumors at children, page 379, M., 1970; Kuznetsov I. D. and Rozenshtraukhl. C. Radiodiagnosis of tumors of a mediastinum, M., 1970; Pathoanatomical diagnosis of tumors of the person, under the editorship of N. A. Krayevsko-go, etc., page 298, M., 1982; Mor son B. C. Histological typing of intestinal tumors, Geneva, 1977; M about s t about f i F. K. a. Price E. B. Tumors of the male genital system, Washington, 1973; S with u 1 1 at R. E. Tumors of the ovary and maldeveloped gonads, Washington, 1979; Serov S. A. Histological typing of ovarian tumors, Geneva, 1973.

H. H. Pokrovsk, L. A. Durnov; L. S. Ro-zenshtraukh (rents.).