Glioma represents a collective term for brain tumors or tumors of the central nervous system that develop from the glial cells (supporting cells of the nervous system). There are both benign and malignant forms of these tumors. Most commonly, gliomas develop in the brain, but the spinal cord can also be affected.
What are gliomas?
Gliomas are tumors that develop from glial cells in the central nervous system. Glial cells represent what are called support cells of neurons. They can be divided into astrocytes, oligodendrocytes, and ependymal cells:
- The majority of glial cells can be classified as astrocytes. These are stellate branching cells that form boundary membranes to blood vessels and the brain surface.
- Oligodendrocytes form the myelin sheaths of axons and present as satellite cells in the white and gray matter of the nervous system.
- The ependymal cells form a single layer of cells around the brain ventricles, separating the cerebrospinal fluid from the brain tissue.
In Greek, the word glia also means glue. So glial cells are connecting cells in the central nervous system. Increased cell growth of these glial cells forms a tumor, which is called a glioma. Gliomas can be classified as astrocytomas, oligodendrogliomas (formerly oligodendrocytomas), ependymomas and mixed gliomas. Their malignancy grade is divided into WHO grades I – IV according to the WHO. Thus, WHO grade I gliomas are considered benign. Gliomas of WHO grade IV are already highly malignant. However, tumors of low malignancy can transform into tumors of high malignancy over time. Astrocytomas account for more than 60 percent of gliomas. An astrocytoma with malignancy grade IV is called a glioblastoma and is the most common malignant brain tumor.
Causes
Not much is known about the causes of gliomas. Only up to five percent of all gliomas are hereditary. They form in neurofibromatosis, Turcot syndrome, or Li-Fraumeni syndrome, among others. In all other cases, the gliomas occur sporadically. An association of ionizing radiation with a clustered occurrence of gliomas has already been established. In addition, it is reported that, based on studies conducted, WHO also classifies intensive use of cell phones as a risk for the development of gliomas.
Symptoms, complaints, and signs
Symptoms of glioma depend on the degree of malignancy and the location of the tumor. Slow-growing tumors may remain asymptomatic for a long time. Only when a certain degree of displacement of the remaining brain tissue occurs do symptoms develop. The first symptom may be an epileptic seizure. Due to the increasing intracranial pressure, severe headaches, constant nausea and vomiting are typical. In fast-growing tumors, headache and paralysis symptoms may occur suddenly. Therefore, there is a risk of confusion with a stroke. As the disease progresses, changes in character may also occur.
Diagnosis and course
To diagnose glioma, an extensive history of the patient’s medical history is first required. If long-lasting headaches occur that are associated with constant nausea and vomiting, glioma may be considered along with many other conditions. If a mass has been confirmed by imaging techniques such as MRI or CT, the next step is to find out what the tumor is. For this purpose, a tissue sample is taken for histological examination in the laboratory. A glioma can be detected in this way. However, it is more difficult to determine the extent of the tumor. Especially malignant gliomas grow into the brain tissue and show a particularly inhomogeneous structure. Thus, it is possible that the glioma cannot be completely detected. Thus, the biopsy may well have detected less malignant areas, even though the tumor is more aggressive elsewhere.
Complications
Glioma usually causes the usual symptoms and complications of a tumor. In this case, the further course also depends greatly on whether the tumor is benign or malignant and whether it has already spread to other regions of the body. It is not uncommon for a glioma to lead to epileptic seizures and other symptoms in the brain. The intracranial pressure may increase, which can lead to severe headaches. Vomiting and nausea also occur.The patient’s quality of life is considerably reduced by the disease. Without treatment, the glioma can also lead to the death of the patient in the worst case. The pain occurs very suddenly. Furthermore, it can also lead to a stroke, which is associated with various complications and discomfort. Complaints in the brain can also have a negative effect on the patient’s psyche and can also lead to depression. If the glioma can be surgically removed, there are no further complications. Furthermore, chemotherapy or radiation may be necessary. If the removal is successful, the quality of life is usually not reduced. However, it cannot be ruled out that a glioma will recur. For this reason, the patient is dependent on regular checkups.
When should you see a doctor?
It is imperative that such a brain tumor be treated by a doctor, otherwise the chances of survival for the affected person are very low. Early diagnosis is very important in the case of an existing brain tumor, because the earlier it is detected, the higher the chances of a complete and quick recovery. Certain signs and symptoms should therefore not be ignored. Inexplicable and constantly persisting headaches may possibly indicate a brain tumor. If the tumor presses on the auditory nerve from the inside, the result is a stabbing earache that general practitioners usually cannot explain. For an exact diagnosis the early visit to the doctor is very important. Only in this way can an appropriate therapy be initiated, so that the chances of survival of the sick person are significantly increased. However, if medical and drug treatment is waived, then the chances of recovery or survival are extremely low.
Treatment and therapy
A WHO grade I glioma can be completely removed surgically. Tumors of this malignancy grade have not yet migrated to brain tissue and have not metastasized. Complete removal of the tumor in this case also means a complete cure. In the case of gliomas with a higher degree of malignancy, surgery is usually no longer sufficient. Radiotia (radio radiation treatment) must be added. This involves targeted radiation of the tumor bed. Currently, investigations are being conducted to determine the extent to which whole-brain irradiation promises success in combating glioma. In the case of glioblastomas, chemotherapy is administered at the same time. The results of glioma treatment are currently not satisfactory. While a low-malignant brain tumor can heal completely after surgery, the life expectancy of a glioblastoma barely exceeds one year after its discovery. But even for gliomas of malignancy grades II and III, therapy is often difficult. These gliomas are characterized by infiltrative growth on the one hand and irregular growth on the other. During surgery often not all tumor foci can be removed. Diffuse infiltration of tumor cells into adjacent healthy tissue eventually makes complete resection of the tumor impossible. However, extensive resection of the glioma is quite reasonable, because then only smaller residual tumors need to be subjected to follow-up therapy. This may delay the formation of a recurrence. In the case of astrocytomas, either radiotherapy or chemotherapy is performed as follow-up therapy. Oligodendroglial tumors are treated exclusively with chemotherapy with PCV.
Prospect and prognosis
As with many other tumor diseases, the prognosis for glioma depends on how early the disease was discovered and how advanced the tumor is. Because of its location in the brain, glioma has two additional characteristics with regard to the prospects for cure that are generally not present in this way in tumors of other organs:
First, with glioma it plays a major role in which part of the brain the tumor is located. If the mass is located in a less important area, it may be possible to operate with a large safety margin in healthy tissue. If this is the case, the chance that all the cells of the tumor can be removed increases and the probability of recurrence decreases significantly, especially in the case of benign tumors. On the other hand, a distinction can also be made between benign and malignant tumor neoplasms in brain tumors. However, this is not always helpful with regard to the prognosis.If a benign tumor is located in an important center of the brain, i.e., if it is inoperable, it is dangerous despite its benign nature. As it grows, it displaces brain structures whose function becomes increasingly compromised. This is due to the fact that cells are destroyed because the rigid skull capsule offers no possibility of escape. For this reason, the prognosis of a benign but fast-growing tumor is also not too favorable if the glioma does not respond adequately to radiation or chemotherapy.
Prevention
There are no general recommendations for prevention from glioma. The causes of gliomas are largely unknown today. According to the WHO, there is some risk of developing glioma from intensive use of cell phones. In the work area, ionizing radiation should also be avoided because all studies agree that it is a high risk factor for glioma development.
Follow-up
Glioma is a disease of the brain that requires consistent follow-up after treatment is complete. Here, on the one hand, it is a matter of regenerating the consequences of the stressful therapy in order to offer the body, but also the mind and soul, the opportunity to recover. On the other hand, of course, it is also a matter of detecting a possible recurrence as early as possible and implementing adequate therapy. Follow-up care is usually carried out by the attending physician, for example a neurologist, in conjunction with the family doctor. Physiotherapists, speech therapists and occupational therapists are often involved in glioma follow-up. The radiologist also provides monitoring through imaging techniques. The patient can effectively support aftercare measures with a healthy lifestyle in everyday life. Sufficient sleep is just as much a part of this as a healthy diet with adequate drinking. Sports and exercise are discussed with the physician and can positively influence motor function problems. Self-help groups support the psychological handling of the disease. Relaxation methods and yoga also help the mind and soul to regenerate. Among relaxation methods, Jacobsen’s Progressive Muscle Relaxation and Autogenic Training are recommended. Conversations with relatives and friends help to cope better with the situation. Social activities not only provide company, but also the distraction that is sometimes needed.
Here’s what you can do yourself
Glioma is a type of tumor that generally requires medical treatment. Nevertheless, there are also some measures for the patient that can be taken in the context of self-help in everyday life. First of all, it is a matter of supporting the regeneration after a treatment such as an operation, radiation therapy or chemotherapy has been carried out. This can be done, for example, by having the patient perform exercises learned in physiotherapy or occupational therapy at home. Often, after an intensive therapy, the affected person also experiences exhaustion. This can often be countered by moderate sporting and fun training. For some sports, such as swimming or climbing, it is important that a possible tendency to seizures is well prevented by medication. Of course, this also applies in particular to driving. In the mental area, dysfunctions can be improved by special memory training or puzzles on one’s own. After being diagnosed with a brain tumor, many of those affected also feel emotionally burdened. The psychological tension can be reduced in different ways: Affected persons who want to come to terms with the disease directly can address their glioma in conversations with familiar people or in self-help groups. Those who do not want to make glioma an issue after therapy and outside of important follow-up visits can stabilize their mental state through yoga or relaxation methods.
