EWING TUMOUR (j. Ewing,
amer. pathologist, 1866 — 1943; a synonym Ewing's sarcoma) — rather rare malignant tumor of a bone.
It is for the first time described in 1921 by Ewing. Among all malignant new growths of bones Yu. the lake makes about 6 — 10%. BB. the lake is, as a rule, observed at children's and youthful age, a thicket at males.
The tumor is usually localized in a metaphysis, a metadiaphysis and a diaphysis of long tubular bones — humeral, femoral, tibial and fibular, but can meet also in pelvic bones, edges, a shovel and other flat bones.
Spread of a tumor on a longitudinal axis of a tubular bone with filling marrowy -
a cash, destruction of cortical substance and the expressed periosteal reaction (fig. 1) is characteristic. Macroscopically fabric of a tumor soft, white or grayish-pink color with numerous sites krovoiz-
Fig. 1. Macrodrug of a fibular bone at Ewing's tumor (a longitudinal cut): considerable
part of a diaphysis of a fibular bone is replaced with the tumoral fabric filling the marrowy channel; shooters specified massive periosteal growths.
liyaniya and necrosis.
Microscopically Yu. the lake consists of small monomorphic cells with rounded oval kernels and almost indiscernible borders of cytoplasm. Chromatin of kernels more often compact, kernels are usually visible. Figures of a mitosis are not numerous. In fabric of a tumor there are no signs of a neoplastic chondrogenesis and bone formation. Rather there are a lot of thin-walled vessels, around to-rykh massive hemorrhages are quite often visible. In some cases cells of a tumor are located around small vessels, creating similarity of pseudo-sockets. With the help CHIC reaction (see) in cytoplasm of cells of a tumor find inclusions of a glycogen. Results electronic mikroskopi-cheskogo researches Yu. islands point to a mezenkhimny origin of cells of a new growth and testify to their low differentiation.
In most cases at the beginning of a disease in a zone of defeat lungs, seldom arising pains appear. In 20 — 22% of observations the first symptom of a disease is the found tumor. Almost in V3 of observations at the beginning of a disease fervescence to 38 — 39 ° is noted. The sizes of a tumor can be various — from the small localized swelling to the massive new growth deforming an extremity. Soft tissues over a tumor are mobile. At a tumor of the big sizes skin over it is usually edematous and hyperemic, with network of expanded venous vessels. The dominating symptom of a disease is pain, various on the intensity — from insignificant, appearing only at an exercise stress, to sharp. Also night pains are characteristic.
In one cases Yu. the lake rather long time is limited to limits of one bone with development of late metastasises in limf, nodes and lungs. Metastasises in other bones appear only in a terminal phase of a disease. In other cases extensive destruction of a bone by a tumor and rough innidiation in other departments of a skeleton is noted. Approximately at 11 — 15% of patients Yu. lakes are observed patol. fractures of bones.
Diagnosis Yu. the lake is based on results of clinical, radiological and morphological researches. Radiological destruction of a bone at Yu. the lake can be melkoochagovy, lamellar and macrofocal. Melkoochagovy destruction meets at localization of a tumor in metaepifizar-ny departments of tubular and flat bones. On the roentgenogram of a bone find a set of the small roundish or oval, indistinctly outlined sites of depression. Lamellar destruction meets at defeat of a diaphysis of tubular bones and leads to longitudinal stratification of cortical substance on a set of plates. At damage of long tubular bones on all their extent melkoochagovy and lamellar destructions can be combined. Macrofocal destruction meets much less often, generally at localization of a tumor in a metaphysis of a tubular bone. On roentgenograms at the same time find the large center of a rounded or oval shape, as if swelling of a bone. Sometimes in the large center of destruction there are partitions that gives it a cellular, cystiform look. Endosteal reaction at Yu. to the lake it is expressed in various degree: from a sclerous border on edge of the center of destruction or insignificant diffusion consolidation of a bone without clear boundary before sharp consolidation of a bone, against the background of to-rogo the marrowy channel is almost not differentiated.
For Yu. the island is characteristic a periostitis (see). At the same time all forms of periosteal growths — linear and layered, hilly and fringed, needle and in the form of a visor meet. They can be hardly expressed or very massive. In the flat bones which do not have a periosteum, this reaction is absent. At defeat of a metaphysis it can be also absent or be expressed only on border with a diaphysis. The linear periostitis meets more often, at Krom reactive bone growths are postponed by parallel layers along a diaphysis. At a needle (spikuloobrazny) periostitis of growth of a periosteum have an appearance of the needles located per-
pendikulyarno to a longitudinal axis of a bone and as if removed from it together with a periosteum the growing tumor (fig. 2).
Variability and variety a wedge, pictures of a tumor of Ewing, from -
Fig. 2. The roentgenogram of a proximal part of a shin at Ewing's tumor (a direct projection): 1 — the diaphysis of a fibular bone is thickened, deformed, the marrowy channel in a zone of a tumor is not differentiated; 2 — massive needle (spikulo-shaped) periosteal growths.
sutstviye pathognomonic rentgenol. signs of damage of a bone, especially in an early phase of development of tumoral process, complicate the correct treatment patol. process.
Differential diagnosis of a tumor of Ewing at patients of young age needs to be carried out with osteomyelitis (see), an eosinophilic granuloma of bones (see), an osteosarcoma (see), a reticulosarcoma of a bone (see the Reticulosarcoma of a bone primary), metastasises to bones of a neuroblastoma (see). At sick 40 — 50 years it is important to exclude also metastasises of cancer in a bone (see the Bone).
Rentgenol. diagnosis of a tumor of Ewing in that phase when the tumor did not extend to soft tissues yet, is extremely complicated. In these cases Yu. the lake it is often indistinguishable from osteomyelitis. The acute beginning of the disease which is quite often developing after an injury and recurrence of a current, to-ruyu against the background of treatment by antibiotics often estimate as subsiding of inflammatory process, complicate a diagnostic task. Reduction of pains and the termination of growth of a tumor after antiinflammatory treatment are not reliable differential diag-nosticheskimi signs since the specified effects are observed also in a wedge, a picture Yu. lake. In favor of the diagnosis of osteomyelitis detection of the sequester testifies, to-ry is always absent at Ewing's tumor.
Rentgenol. the manifestations characteristic for Yu. lakes, can be observed also at an eosinophilic granuloma of bones (see). For the correct interpretation patol. process it is necessary to consider distinctions in a wedge, a picture of a disease (considerable destruction of a bone against the background of poorly expressed a wedge, manifestations in case of an eosinophilic granuloma of a bone) and data
gistol. researches of the fabric received from the center of defeat.
Differential diagnosis of a tumor of Ewing and an osteosarcoma in some cases happens simple. At an osteosarcoma of pain appear early and have more intensive character; process proceeds with the progressing deterioration, without remissions and temporary delay or a stunt of a tumor. At rentgenol. a research the center of defeat comes to light preferential in the field of a metaphysis of a long tubular bone (most often distal department femoral or proximal department tibial bones), further the center reaches a bast layer of a bone with the subsequent distribution to surrounding soft tissues and emergence of spikuloobrazny reaction of a periosteum — on border with not changed bone the periosteal visor comes to light. An important distinguishing character of an osteosarcoma are the centers of an osteogenesis in a myagkotkanny part of a tumor. Diagnostic difficulties are usually presented by metafizarny localization Yu. the lake, as revealed at rentgenol. a research reaction of a periosteum can be in the form of so-called spicules and a periosteal visor. A biopsy from the center of defeat with the subsequent morfol. a research of fabric of a tumor allows to make the correct diagnosis.
Differential diagnosis Yu. the lake and reticulosarcomas of a bone presents great difficulties and the hl is based. obr. on results gistol. researches of a tumor. However in some cases the nek-ry wedge, signs allow to distinguish these tumors: a top general condition of patients with a reticulosarcoma and its disturbance at patients Yu. lake; a difference in growth rate of a tumor — Yu. the lake develops much quicker than a reticulosarcoma; identification of a reticulosarcoma at more advanced age; big frequency patol. changes at a reticulosarcoma. Specified a wedge, signs have no crucial importance in diagnosis. They can be found at localization of tumors in long tubular bones (at damage of flat bones a wedge, a picture Yu. the lake and reticulosarcomas it is almost identical); these signs can be revealed only by comparison a wedge, these big groups of patients. Plays a crucial role in diagnosis systematic gistol. a research taking into account all clinicoradiological symptomatology. But also at gistol. a research of these new growths differential diagnosis is complicated. Distinguishing characters are the developed network of argyrophil fibers at a reticulosarcoma and existence of a glycogen in cells at Ewing's tumor.
At metastasises of cancer in a skeleton the differential diagnosis with Yu. the lake is based on the detailed accounting of all clinicoradiological data and on an obligatory morfol. research of a tumor.
The treatment combined (see Tumours, treatment). Considering high radio sensitivity Yu. the lake conventional by method of local influence is radiation therapy (see). The remote gamma therapy is most widespread (see). In view of distribution inherent to this tumor on the marrowy channel and quite often considerable extent of process, all bone with the center of defeat is subject to radiation. Only at children because of danger of dead stop of growth of a bone switching off from the radiation zone of area of an opposite epiphysis is reasonable. The single focal absorbed dose makes 180 — 200 is glad (1,8 — 2 Gr), a total focal dose — 5000 — 6000 is glad (50 — 60 Gr). The technique of radiation therapy of a tumor of flat bones (an edge, pelvic bones, a skull) depends on localization, a form and the sizes of a new growth. Within the first week of radiation pains decrease, the general condition of the patient improves, the myagkotkanny component of a tumor is reduced. For impact on primary center and clinically not revealed metastasises Yu. lakes along with radiation therapy carry out treatment by antineoplastic means (see). At inefficiency of radiation therapy and chemotherapy an operative measure — more often amputation of an extremity is shown.
The forecast is adverse though recently in connection with use of modern antineoplastic means the tendency to improvement of results of treatment is planned.
Bibliography: Blochin H. N and Pere-vodchikova N. I. Himioterapiya of tumoral diseases, M., 1984; In and-nogradova T. P. Tumors of bones, page 183, M., 1973; Reynberg S.A. Radiodiagnosis of diseases of bones and joints, book 2, page 432, M., 1964; Shai-ovich F., etc. Histologic classification of bone tumors, the lane with English, page 39, Geneva, 1974; Ewing J, Diffuse endothelioma of bone, Proc. N. Y * Path. Soc., y. 21, p. 17, 1921; Lichtenstein L. Bone tumors, p. 267, St Louis, 1977; Pomeroy T. C. a. Johnson R. E. Combined modality therapy of Ewing’s sarcoma, Cancer, v. 35, p. 36, 1975; Schajowicz F. Tumors and tumorlike lesions of bone and Joints, p. 244, N. Y. a. o., 1981; Sherman R. S. a. Soong K. Y. Ewing’s sarcoma, Radiology, v. 66, p. 529, 1956.
BB. H. Nightingales, JI. A. Eremina;
I. G. Lagunova (rents.).,