Spinal meningioma is a neoplasia of the spinal canal, originating in the spinal membranes. It is clinically manifested by progressive radicular syndrome with a transition to the symptoms of half and full damage to the spinal cord diameter at the level of the tumor location. Spinal meningioma is diagnosed according to the neurological status, MRI of the spine, histological analysis of intraoperatively obtained material. Neurosurgical treatment: radical removal is recommended, stereotactic surgery is possible according to indications. If the meningioma is malignant, it requires additional pre- and/or postoperative radiation therapy.
ICD 10
D32.1
General information
Spinal meningioma is much less common than similar brain tumors and occupies 1.2% of the total number of meningiomas. In the structure of primary spinal cord tumors, meningiomas account for 15-30%. In most cases, spinal meningioma is an intradural extramedullary tumor. According to clinical observations, specialists in the field of neurology and neurosurgery have described separate extradural, extraintradural meningiomas. In 99% of cases, meningioma of spinal localization is a benign neoplasm. The most frequent localization of the tumor (70% of cases) is the thoracic spine, typically the ventrolateral location of neoplasia in relation to the spinal cord. More than half of the cases of the disease occur in patients over the age of 60. Women get sick 6-10 times more often than men.
Causes
The etiofactors of the occurrence of neoplasia have not been fully studied. The information about them is of an assumed nature. The most likely is the multifactorial mechanism of the disease development. The known etiological prerequisites can be divided into 3 main groups:
- Exogenous. Assume the harmful effects of various adverse environmental factors: ionizing radiation, nitrates consumed with food, carcinogens contained in food, inhaled air. These influences cause “breakdowns” in the genetic apparatus of the cell, leading to a change in its properties.
- Endogenous. A certain role is played by a decrease in the antitumor protection of the body, which partially explains the predominantly elderly age of patients. The dysfunction of the antitumor mechanism, which normally destroys mutated cells, causes the reproduction of atypical cellular elements of the meninges.
- Hereditary. The increased risk of meningiomas in patients suffering from neurofibromatosis indicates the genetic determinacy of the pathology. The localization of the genetic defect is assumed to be on the 22nd chromosome.
Pathogenesis
The effect of the above mentioned etiofactors leads to a change in the basic properties of individual cells of the soft meninges of the spinal cord. Not destroyed by antitumor protection, altered (atypical) cells begin to divide intensively, forming into neoplasia. Tumor cells have lower differentiation than normal ones. In the vast majority of cases, meningioma is benign. Rarely, it consists of extremely low-differentiated cellular structures that cause the malignant properties of the tumor.
Morphologically, the spinal meningioma is a dense node, more often has a capsule. Extramedullary expansive growth of the neoplasm is typical, pushing apart adjacent tissues. The primary clinical symptoms are caused by compression of the spinal roots. The spinal cord is affected due to ischemia during compression by the tumor of the vessels feeding it and as a result of direct compression by growing neoplasia. Compression of the pathways causes the appearance of neurological deficit below the level of tumor localization.
Classification
By localization, spinal meningioma can be cervical, thoracic, lumbosacral. Neoplasia with expansive growth and multicentric development are isolated from several tumor foci. According to the histological structure, the meningioma is classified into fibroblastic, meningotheliomatous, psammomatous, mixed, light-cell, papillary, choroid, rhabdoid. In clinical practice, the classification that takes into account the nature of growth, the degree of malignancy and prognosis has become the most widespread. In accordance with these criteria , there are 3 main variants of spinal meningiomas:
- Type I. Slow-growing benign neoplasia. They give the least number of relapses after neurosurgical removal. They have the most favorable prognosis. 94.5% of spinal meningiomas belong to this group.
- Type II. Atypical tumors characterized by rapid growth, a high probability of recurrence. Due to the nature of the growth, they were called “aggressive”. Prognostically less favorable than neoplasia of the previous group. Observed in 4.7% of clinical cases.
- Type III. Malignant meningiomas with aggressive invasive growth, recurrence. They are capable of forming metastases. Have an unfavorable prognosis, make up 1%.
Symptoms
A long subclinical course is characteristic, due to the small size and slow increase in neoplasia. Clinically, the disease debuts with the symptoms of the classic radiculopathy. First, there are symptoms of irritation of the spinal root (intense radiating pain, paresthesia). Subsequently, the intensity of the pain syndrome decreases, a neurological deficit appears and increases (decreased sensitivity, muscle weakness, hyporeflexia) associated with loss of function of the root squeezed by the tumor. These clinical manifestations are localized in the innervation zone of the affected root.
Spinal neoplasia of the thoracic region can give symptoms that mimic the defeat of somatic organs. When the tumor is localized at the level of the lower thoracic segments, epigastric pains occur, resembling manifestations of gastritis, shingling pains characteristic of acute pancreatitis. With the left-sided location of the formation, cardialgia occurs, requiring differentiation from angina pectoris. The radicular stage of the tumor lasts from several months to five years.
As the spinal meningioma grows, it causes compression of the spinal cord, manifesting Brown-Sekara syndrome. Below the level of neoplasia location, central paresis and loss of deep sensitivity are observed in the homolateral half of the body, and superficial hypesthesia is observed in the contralateral half. Neurological deficit increases rapidly, acquires a symmetrical character with symptoms of complete damage to the spinal diameter. Below the lesion level, there is a rough central paresis, pronounced total hypesthesia, trophic disorders; arbitrary control of pelvic organ function is violated.
Complications
Over time, compression of the spinal cord leads to degeneration and death of its neurons, atrophy of nerve fibers of the pathways. The resulting neurological deficit becomes irreversible, even after the removal of the tumor, the patient remains disabled. At the level of the lesion, muscle atrophy occurs, below the spastic increase in muscle tone leads to the development of joint contractures. Trophic disorders in denervated tissues are accompanied by a decrease in the protective function of the skin, which is accompanied by their slight injury and difficult regeneration. These changes favor infection with the penetration of infectious agents into the bloodstream, the development of sepsis. Pelvic organ disorders require constant catheterization of the bladder, which increases the risk of infection with the occurrence of urethritis, cystitis, ascending pyelonephritis. The most dangerous complication of malignant meningiomas is metastasis.
Diagnostics
Early diagnosis is difficult, since spinal meningioma debuts with symptoms of sciatica, typical for manifestations of osteochondrosis, and the age of most patients coincides with the period of manifestation of degenerative changes in the spine. It is possible to suspect a neoplasm in the case of a young patient, frequent recurrence of pain syndrome, the appearance of symptoms of “loss” (neurological deficit), low effectiveness of standard therapy for sciatica. The main stages of diagnosis are:
- Neurologist’s examination. In the neurological status, depending on the stage and localization of the process, radicular sensitivity disorders, central mono-, hemi-, para- or tetraparesis, Brown-Secar dissociation, total loss of sensitivity, etc. are determined. The results of the neurologist’s examination suggest the level and prevalence of the lesion.
- Spinal MRI. It is the main method of diagnosis of neoplasia. MRI of the spine helps to determine the size, exact location, the nature of the growth of the formation, the degree of spinal compression. If there are contraindications to magnetic resonance imaging, CT myelography is performed.
- Histological examination. Histology of the surgical material is carried out, in doubtful cases — intraoperative examination. Microscopic and histochemical analysis makes possible accurate morphological verification of the tumor, allows you to establish a definitive diagnosis.
Spinal tumor is differentiated from radiculitis, intervertebral hernia, spinal root neurinoma, hematoma, myelitis, syringomyelia. When located in the thoracic region, there is a need to exclude gastroduodenitis, acute abdomen, coronary heart disease. During MRI, meningioma requires differentiation from other extramedullary spinal tumors: neurofibromas, lipomas, hemangiomas, chondromas.
Treatment
The most acceptable method of treatment is radical removal of tumor formation. The choice of therapeutic tactics is carried out by a neurosurgeon in accordance with the localization, nature and prevalence of the process, the general somatic condition of the patient. There are 3 main methods of treatment:
- Open operation. Radical removal of meningioma is performed using microsurgical techniques. Access to the tumor is a laminectomy. To prevent relapse, complete removal of tumor tissues is important. In order to increase the radicality of the operation, embolization of the vessels feeding the meningioma is pre-performed.
- Stereotactic surgery. The meningioma is subjected to remote, precisely directed irradiation with ionizing (gamma ray) or X-ray (cyberknife) radiation. Stereotactic removal is the most gentle technique that does not require an incision, minimizing the impact on surrounding tissues. Its use is limited by a high percentage of recurrence.
- Antitumor therapy. Radiation therapy is prescribed postoperatively or palliatively if it is impossible to completely remove the neoplasm, a malignant process. Dosimetric planning is carried out by a radiologist on an individual basis.
Prognosis and prevention
Spinal meningioma has a predominantly favorable prognosis. After radical surgical treatment of type I tumors, the risk of recurrence is 15%. Late diagnosis and treatment aggravate the unfavorable prognosis, as they lead to the formation of irreversible changes, disability of the patient. Specific prevention has not been developed, general preventive measures are reduced to limiting adverse oncogenic effects. Secondary prevention is aimed at earlier detection of relapses, includes regular monitoring of the patient by a neurosurgeon, and control MRI.