EPENDYMOMA (ependymoma) — the neuroectodermal tumor developing from the ependimotsit covering ventricles of a brain and the spinal channel.
According to JI. I. Smirnova (1962), AA. make apprx. 3% of all tumors of c. N of page (see the Brain, tumors). AA. it is observed preferential at persons of young age (middle age sick 22 years).
Ependymomas of a brain are located intraventrikulyarno more often, paraventrikulyar-ny localization of these tumors meets less often. AA. a spinal cord, coming from ependymas of the central channel, are located intramedullyarno, and developing from an ependyma of a terminal ventricle or terminal thread — ekstramedullyarno. Macroscopically E. has an appearance it is accurate the delimited node (fig. 1) more often, in Krom on a section large smooth-bore cysts can be defined. Intramedullary E. quite often takes the form of a pin or a spindle. In a zone of initial growth of a tumor, as a rule, its clear boundary is not with tissue of a brain.
According to the International histologic classification of tumors of the central nervous system (1979) allocate four types E. Basic gistol. type is actually E., for a cut existence of perivascular and true «sockets» is characteristic. Perivascular «sockets» («pseudo-sockets», «radiant crown») are formed by the cells of a tumor located around blood vessels (fig. 2). In true «sockets» tumor cells are located around the channels covered by an ependimarny epithelium. Meets papillary E.T less often consisting from vorsin and the trabeculas covered with an ependimarny epithelium. This type of a tumor has extramedullary localization (an ependymoma of a horse tail) more often. At gistol. a research in cases papillary E. it is necessary to carry out the differential diagnosis with polecats-oidpapillomoy (see). Miksopapil-
Fig. 1. Macrodrug of a brain (a frontal section) at an intraventricular ependymoma of the third ventricle:
shooters specified a tumor in the form of accurately delimited node filling a gleam of the third ventricle of a brain.
Fig. 2. Microdrug of an ependymoma of a brain (the main histologic type — actually an ependymoma): shooters are specified characteristic p by e r 11 in and with to at l I r in N y e structures — «pseudo-sockets»; coloring hematoxylin-eosine; x 4 00.
lyarny E. also it is localized ekstramedullyarno, is more often in a horse tail, and it is characterized by mucous dystrophy (see) and edematous fusion of fabric with formation of mucous cysts. The sub-ependymoma (a subependimarny nodal astrocytoma, ependimoastrotsi-volumes, an ependimoglioma), develops from subependnmarny clays and consists of islands of the monomorphic ependi-marny cells lying in a dense stroma from glial a demon of cellular fibers. More often the page of an ubependimom has the form of a node and is located intra-ventrikulyarno.
Krom of these gistol. types allocate malignant option E. (anaplastic E., an ependymoblastoma), characterized typical morfol. signs anapla-31Sh. At this option E. metastasises can extend on a subarachnoid space. P. Bailey, X. Cushing (1926), L. I. Smirnov (1962), B. S. Homin-sky (1969) allocate also very rare option of a tumor — epithelial E. (ependimoeshgteliy, or a neuroepithelioma of a brain), consisting of epithelial-like cells.
Wedge, picture E. is defined by localization of a tumor. At intraventricular E. with occlusion liquor-nykh of ways most often the first and main symptom of a disease is gipertenzionno-gidrotse-falny a syndrome, for to-rogo the headaches which are followed by vomiting, hypostasis of disks of optic nerves, secondary giperten-zionny changes on a kraniogramma are characteristic (see. Hypertensive syndrome). At E. a side ventricle symptoms of intracranial hypertensia can be followed by moderately expressed signs of focal defeat of the corresponding hemicerebrum. For E. the third or fourth ventricles, along with the gipertenzionno-guide-rotsefalnym a syndrome, clearer local (focal) symptoms are typical. At a tumor of the third ventricle hormonal disturbances (obesity or a cachexia, not diabetes mellitus, sexual disturbances) are noted; at a tumor of the fourth ventricle — symptoms of irritation of the educations creating it — the fixed position of the head, paroxysmal headaches, the vomiting which is not connected with a headache, cerebellar frustration, symptoms nuclear or radicular p about r and e in N and I che r e p in N about - brain nerves, Bruns's attacks (sharp dizziness, change of pulse rate, breath, a kollai-toidny state).
Intramedullary E. causes a picture of gradually developing cross damage of a spinal cord. For E. a horse tail radicular pains, disorders of function of pelvic bodies, muscular atrophies, paresis, disturbance of sensitivity, loss of tendon jerks on the lower extremities are characteristic.
Diagnosis E. a brain is based generally on data of methods of visualization of ventricles of a brain — a computer tomography (see the Tomography computer), ventrikulografiya (see), a pneumoencephalography (see). Diagnosis E. a spinal cord it is based on the general principles of diagnosis of all tumors of a spinal cord — a spinal puncture (see) with l ikvo r about d and N and m and ches to both m and test of m and (see) and definition of protein content in tserebros i of and and and l and about y and dkos in t and (with m), the ascending and (or) descending mi-elografiya (see).
Treatment E. operational, in some cases with the subsequent remote radiation therapy (see), edges it is most shown at malignant option of a tumor. As a rule, AA. it is possible to remove considerably, but at tumors, coming from walls of the third ventricle, a bottom of the fourth ventricle, at intramedullary E. big extent and AA. a horse tail, acquiring roots of the lumbar nerves forming a horse tail, operation is accompanied by considerable difficulties. In these cases use of the microsurgical equipment is required (see M an ikrolirurgiya).
The forecast rather favorable is also defined by localization of a tumor and radicalism of operation. The forecast at an anaplastic eiyendimoma is less favorable.
See also Brain, tumors; Spinal cord, tumors.
Bibliography: Badmayev K. N. and
With m and r N about in R. V. Radionuclide diagnosis and radiation therapy of diseases of a nervous system, M., 1982; R and z d about l ý-with to and ii I. Ya. Klinika of tumors of a brain, L., 1957; it, Tumours of a spinal cord and backbone, L., 1958; With m and r N about in L. I. Tumors of a head and spinal cord. M, 1902; X about m and not to and y B. S. Histologic diagnosis of tumors of the central nervous system, M., 1969; Brain tumors, ed.
by D. G. T. T ho mas a. DIG r a li a m, L. — In about s to n, 1980; Ziilch K. J. Die H i rn-gesclnvulste in biologischer und morpliolo-gischer Darstellung, Lpz., 1958; about N of e, Atlas of the histology of brain tumors, V. a. o., 1971; about N of e, Histological typing of tumors of the central nervous system, Geneva, 1979.
T. M. Vikhert, B. A. Kadashev.