Astrotsitoma of a brain
Astrotsitoma of a brain — primary intracerebral neyroepitelialny (glial) tumor originating from star-shaped cages (astrotsit). Astrotsitoma of a brain can have various degree of a zlokachestvennost. Its manifestations depend on localization and are subdivided into the general (weakness, appetite loss, headaches) and focal (a hemiparesis, a gemigipesteziya, an incoordination, a hallucination, speech disturbance, change of behavior). Astrotsitoma of a brain is diagnosed on the basis of clinical yielded, results of KT, MPT and a histologic research of fabrics of a tumor. Treatment of an astrotsitoma of a brain usually represents a combination of several methods: surgical or radio surgical, beam and chemotherapeutic.
Astrotsitoma of a brain
Astrotsitoma of a brain is the most widespread kind of glial tumors. About a half of all gliomas of a brain is presented by astrotsitoma. Astrotsitoma of a brain can arise at any age. More often than others the astrotsitoma of a brain is noted at men aged from 20 up to 50 years. At adults the most characteristic localization of an astrotsitoma of a brain is white substance of hemispheres (a tumor of hemispheres of a brain), at children damage of a cerebellum and a trunk of a brain meets more often. Occasionally at children damage of an optic nerve (a glioma of a hiazma and a glioma of an optic nerve) is observed.
Brain astrotsitoma etiology
Astrotsitoma of a brain is result of tumoral regeneration of astrotsit - the glial cages having the form of a star for which they are also called star-shaped cages. Until recently was considered that astrotsita perform the support supporting function in relation to TsNS neurons. However the last researches in the field of neurophysiology and neurology showed that astrotsita perform protective function, preventing traumatizing neurons and absorbing the excess chemicals which are formed as a result of their activity. They provide food of neurons, participate in regulation of functions of a hematoencephalic barrier and condition of a brain blood-groove.
Exact data on the factors provoking tumoral transformation of astrotsit are absent so far. Presumably a role of the trigger as a result of which the astrotsitoma of a brain develops play: excess radiation, chronic influence of harmful chemicals, onkogenny viruses. The essential part is assigned to also hereditary factor as genetic breakages in TP53 gene are found in patients about astrocytomine of a brain.
Classification of an astrotsitoma of a brain
Depending on a structure of the cages of an astrotsitom of a brain making it can be "usual" or "special". Treat the first group a fibrillyarny, protoplasmatic and gemistotsitarny astrotsitoma of a brain. The piyelotsitarny (pilloidny), subependimalny (glomerulyarny) and mikrotsistny tserebellyarny astrotsitoma of a brain enters into group of "special".
According to the WHO classification of an astrotsitoma of a brain are subdivided on zlokachestvennost degree. The "special" astrotsitoma of a brain — piyelotsitarny belongs to the I degree of a zlokachestvennost. The II degree of a zlokachestvennost is characteristic for "usual" good-quality astrotsity, for example, fibrillyarny. To the III degree of a zlokachestvennost the anaplastichesky astrotsitoma of a brain, belongs to the IV degree — a glioblastoma. About 60% of tumors of a brain while the high-differentiated (good-quality) astrotsitoma make only 10% are the share of a share of a glioblastoma and an anaplastichesky astrotsitoma.
Brain astrotsitoma symptoms
Clinical manifestations by which the astrotsitoma of a brain is followed can be divided into the general, noted at any arrangement tumors, and local or focal, depending on process localization.
The general symptoms of an astrotsitoma are connected with the increase in intra cranial pressure caused by it, the irritativny (irritating) influence and toxic influence of products of metabolism of tumor cells. Treat the general manifestations of an astrotsitoma of a brain: headaches of constant character, lack of appetite, nausea, vomiting, doubling in eyes and/or emergence of fog before eyes, dizzinesses, changes of mood, an adynamy, decline in the ability to concentration of attention and a memory impairment. Epileptic seizures are possible. Often the first manifestations of an astrotsitoma of a brain have the general nonspecific character. Over time depending on degree of a zlokachestvennost of an astrotsitoma there is a slow or bystry progressing of symptomatology with the advent of the neurologic deficiency testifying to the focal nature of pathological process.
Focal symptoms of an astrotsitoma of a brain result from destruction and a sdavleniye a tumor of cerebral structures, close to it. For polusharny astrotsity a brain decrease in sensitivity (gemigipesteziya) and muscular weakness (hemiparesis) in a hand and a leg opposite to the struck hemisphere of the side of a body is characteristic. Tumoral damage of a cerebellum differs in violation of stability in a standing position and when walking, problems with coordination of movements.
Location of an astrotsitoma of a brain in a frontal lobe is characterized by the inertness which is sharply expressed by the general weakness, apathy, decrease in motivation, attacks of mental excitement and aggression, a memory impairment and mental abilities. The people surrounding such patients note changes and strangenesses in their behavior. At localization of an astrotsitoma in a temporal share take place of speech disturbance, violations of memory and hallucinations various in character: olfactory, acoustical and flavoring. Visual hallucinations are characteristic of the astrotsitoma located on border of a temporal share from occipital. If the astrotsitoma of a brain is localized in occipital shares, then along with visual hallucinations it is followed by various violations of sight. The parietal astrotsitoma of a brain causes frustration of a written language and violation of small motility.
Diagnostics of an astrotsitoma of a brain
Clinical examination of patients is conducted by the neurologist, the neurosurgeon, the ophthalmologist and the otolaryngologist. It includes neurologic survey, ophthalmologic inspection (visual acuity definition, a research of fields of vision, an oftalmoskopiya), a threshold audiometriya, a research of a vestibular mechanism and the mental status. Primary tool inspection of patients about astrocytomine of a brain can reveal the increased intra cranial pressure according to Ekho-EG and existence of paroksizmalny activity according to an electroencephalography. Identification of focal symptomatology during neurologic inspection is the indication to carrying out KT and MPT of a brain.
Astrotsitoma of a brain can be found also at an angiography. Allows to establish the exact diagnosis and to define tumor zlokachestvennost degree a histologic research. Receiving histologic material is possible during a stereotaksichesky biopsy or intraoperatsionno (for the solution of a question of the volume of surgical intervention).
Treatment of an astrotsitoma of a brain
Depending on brain astrotsitoma differentiation degree its treatment is carried out by one or several of the specified methods: surgical, chemotherapeutic, radio surgical, beam.
Stereotaksichesky radio surgical removal is possible only at the small size of a tumor (to 3 cm) and is carried out under tomographic control by means of the patient of a stereotaksichesky frame who is put on the head. At a brain astrotsitoma this method can be used only in rare instances of the good-quality course and limited growth of a tumor. The volume of the surgical intervention which is carried out by cranial trepanation depends on the nature of growth of an astrotsitoma. Often because of diffusion growth of a tumor in surrounding brain fabrics its radical surgical treatment is impossible. In such cases palliative operation for reduction of the sizes of a tumor or the shunting operation directed to decrease in hydrocephaly can be performed.
Radiation therapy of an astrotsitoma of a brain is carried out by way repeated (from 10 to 30 sessions) external radiation of the struck area. The chemotherapy is carried out by cytostatics with use of oral medicines and intravenous administrations. It is given preference in cases when the astrotsitoma of a brain is observed at children. Active developments on creation of the new chemotherapeutic medicines capable to influence selectively tumor cells are lately conducted, without having at the same time the damaging effect on healthy.
Forecast of an astrotsitoma of a brain
The adverse forecast of an astrotsitoma of a brain is connected with its mainly high degree of a zlokachestvennost, frequent transition of less malignant form to more malignant and almost inevitable retsidivirovaniye. At persons of young age more widespread and malignant current astrotsity is observed. The forecast is optimum if the astrotsitoma of a brain has the I degree of a zlokachestvennost, but even in this case longevity of the patient does not exceed 5 years. For an astrotsitoma of the III-IV degree it is time averages 1 year.