CHORDOMA (Greek chorde a string + - orna) — the malignant tumor developing from the remains of a back string (chord) representing jellylike pulpozny kernels of intervertebral disks.
The term is offered in 1858 by I. Müller. The chordoma meets seldom and makes no more than 1% of all malignant tumors of a skeleton. The tumor arises in zones of regression of a chord more often (see the Backbone; embryology), it is preferential in occipital and basilar area (a cranial chordoma) or a sacrococcygeal zone of a backbone. Less often the chordoma is found in cervical, chest or lumbar departments of a backbone and it is exclusively rare — in jaws, paranasal sinuses and a shovel. Cranial chordomas are found in, to a yozrasta of 30 — 50 years, sacrococcygeal chordomas — aged apprx. 50 years, is preferential at men.
Macroscopically the chordoma represents the lobular masses to a greater or lesser extent destroying a bone and getting into adjacent soft tissues. In most cases the chordoma looks encapsulated, but on a marrowy cavity extends without clear boundary. Fabric of a tumor myag Kaya, places jellylike, grayish or bluish-white color. On a section gelatinous translucent sites alternate with cystous cavities and the centers of hemorrhages. Along with it rather dense or crumbling sites of fabric can meet. Existence of the centers of obyzvestvle-N iya is possible (with m. To it is scarlet tsinoz).
Gistol. the picture is very characteristic — uneven lobular and tyazhisty or trabecular accumulations typical large polygonal or j of cylindrical cells of various sizes with eosinophilic plentiful cytoplasm and a significant amount of vacuoles, small round usually eccentric the located kernel (fi-zaliformny cells) are visible. Cells of a chordoma along with mucin contain a significant amount of a glycogen. The amount of basphilic interstitial substance between segments, tyazha and separate cells varies over a wide range. In some cases tumor cells differ in special polymorphism — have various sizes and the form, contain sharply hyperchromic or doubled kernels, mitoses quite often come to light. These signs optional correlate with the growth rate or emergence of metastasises.
Wedge, symptoms are defined by localization of defeat, are connected with destruction of bone structures and infiltration of adjacent fabrics and bodies. In most cases the chordoma arises and develops imperceptibly. The wedge, symptoms at a cranial chordoma appear earlier, the sacrococcygeal chordomas and chordomas which are localized in chest department of a backbone can proceed long time asymptomatically. The cranial chordoma is followed golovnykhm by pains, vision disorders, quite often for a row of years disorders of function of a nasopharynx are observed that is caused by growth of a tumor in its party. The mass of a tumor burgeoning in a pelvic cavity at sacrococcygeal localization of a chordoma can lead to the shift and a prelum of a rectum, bladder and the corresponding dysfunctions of these bodies. The expressed local and remote symptomatology results from a prelum the growing tumor of nerves and nervous trunks.
Radiological the most constant sign of a chordoma is destruction of a bone tissue. Usually it is the osteolytic center of irregular shape with destruction of compact substance of the corresponding bone educations (see Ossifluence) and an ekstraossalny component of the bigger or smaller size. Approximately in half of cases on roentgenograms it is possible to find intra-tumoral calcificats. Significant assistance in diagnosis, especially establishment of extent of defeat at chordomas of various localization, can render an angiography (see), a pneumoencephalography (see), scanning (see) a brain, a computer tomography (see the Tomography computer).
Treatment operational with removal of the greatest possible volume of a tumor. When the full oncotomy is impossible, attempts of performing radiation therapy (see) with use of perhaps high exposure doses are made. There are data that the incomplete oncotomy can lead to long remission.
Remote forecast always adverse. Metastasises usually appear after long a wedge, currents and a repeated recurrence.
See also Bone, tumors. Bibliography: Vinogrado in and T. P. Tumors of bones, page 50, M., 1973; Pathoanatomical diagnosis of tumors of the person, under the editorship of N. A. Krayevsky, etc., page 416, M., 1982; Sh and y about in and the p F. and d river. Histologic classification of bone tumors, page 45, Geneva, WHO, 1974; S with h a j about-w i with z F. Tumors and tumorlike lesions of bone and joints, p. 377, N. Y. a. o., 1981.
BB. H. Nightingales.