Brain tumors constitute approximately 5% of all tumoral diseases. There are various types of brain tumors. Some brain tumors are benign – slowly growing – low grade (benign), while some brain tumors are malignant – capable of growing – spreading – high grade (malignant). Brain tumors can be tumors that develop from intracranial structures (brain-cerebellum-brain membrane-nerves, etc.) (primary brain tumors) or tumors that spread into the skull from other organs of the body through blood or neighborhood (secondary or metastatic tumors).
Brain tumors seen in children are mostly located in the lower part of the brain and the cerebellum region (infratentorial).
In adults, it is located in the upper part of the brain (supratentorial).
The most common tumors in children are brainstem, cerebellum and optic nerve gliomas, congenital craniopharyngiomas and teratomas.
Glial tumors that develop from brain tissue, meningiomas of meningeal origin, acoustic neuromas of nerve sheath origin, and pituitary gland tumors are common in adults and middle ages.
In older ages, metastatic tumors that spread from other organs to the brain are common.
Symptoms of Brain Tumors
Brain tumors give different findings depending on their location in the brain, type and size. Headache, nausea, vomiting, and increased intracranial pressure are the most common symptoms.
- Headache that gets worse in the morning and continues throughout the day,
- Seizures,
- Nausea-vomiting,
- Loss of sensation or weakness in arms and legs,
- Difficulty walking, balance disorder
- Change in vision and/or abnormal eye movements,
- Insomnia,
- Personality and memory changes
- Speech changes
These changes may also occur due to another problem, such as brain tumors.
Diagnosis of Brain Tumors
First of all, detailed questioning of complaints, family history and a complete physical examination are required. After the general examination, a detailed “neurological examination” should also be performed. Whether there is insomnia, muscle strength, coordinated movements of muscles, reflexes and response to pain should be examined. Eye movements should also be examined in detail. Depending on the results of the physical and neurological examination, one or more of the following “radiological examinations” may be requested:
Brain Tumor Examinations
- Computerized brain tomography,
- Magnetic resonance imaging (MR) examination, MR-angiography, MR-Spectroscopy, Diffusion MR, Functional MR, MRtractography
- Cerebral angiography,
- Positron emission tomography (PET), SPECT
- Electroencephalography (EEG)
Treatment of Brain Tumors
Treatment of brain tumor depends on many factors. Type of brain tumor, location, diameter of the tumor, age and general health of the patient; It is important in choosing the treatment method. The treatment method and method of application are different for child and adult patients.
In the treatment of brain tumors; “Surgery”, “Radiotherapy”, and “Chemotherapy” can be used. The type of surgery is decided according to the diameter and location of the tumor. Radiotherapy kills cancer cells using high-energy rays. The use of anticancer drugs is called Chemotherapy. These treatment methods are used separately in some patients and together in some patients.
In the treatment team of brain tumors; There must be a neurosurgeon, “radiation oncologist”, “medical oncologist”, physical therapist, speech therapist and dietician.
Before starting treatment, patients are given “steroids” to prevent brain edema and “anticonvulsant” drugs to prevent and control seizures. If there is hydrocephalus, which means enlargement of the brain waterways due to blockage, malabsorption or increase in the brain waterways, a shunt can be installed.
Surgical Treatment of Brain Tumors
It is the method primarily used in the treatment of brain tumors. The aim is to remove the entire tumor without damaging normal brain tissue. The tumor should be removed as much as possible. For this purpose, technological methods that support surgery such as microsurgical technique, endoscopy, mapping, awake surgery and navigation can be additionally used depending on the location and location of the tumor.
However, if the tumor cannot be removed without damaging the brain tissue, some of it can be left. For pathological diagnosis, partial tumor removal may be performed to reduce the increased intracranial pressure due to the mass effect of the tumor and correct the associated findings, and to increase the effect of other treatment methods by reducing the size of the tumor as much as possible. Even removing a part of the tumor reduces symptoms of pressure in the brain, and the remaining part can be treated with radiotherapy and/or chemotherapy.
Biopsy
By taking a very small part of the tumor with a biopsy, pathological diagnosis can be made and it helps to choose the treatment method.
Radiotherapy in Brain Tumors
Radiotherapy is the use of powerful radioactive rays to damage cancer cells and stop their growth. This treatment is not used as a substitute for surgery for brain tumors. It is generally used for the treatment of tumor tissue remaining after surgery or if surgery cannot be performed.
Radiotherapy in Brain Tumors
Radiotherapy is the use of powerful radioactive rays to damage cancer cells and stop their growth. This treatment is not used as a substitute for surgery for brain tumors. It is generally used for the treatment of tumor tissue remaining after surgery or if surgery cannot be performed.
External radiotherapy: It is radiation therapy given from outside with the help of large devices. It is given for 5-6 weeks, 5 days a week. The treatment regimen depends on the type and size of the tumor and the location of the disease.
Brachytherapy: It is a treatment performed by placing radioactive material directly into the tumor. The implant is left in the brain for a short time or permanently. The implant treats the patient by giving some radiation every day.
Stereotaxic radiosurgery: It is a method used especially in small and deep-seated tumors. It is a form of treatment performed by applying multiple beams at different angles to focus on the target point after the location of the tumor is determined by CT or MRI.
Chemotherapy in Brain Tumors
Chemotherapy is the killing of cancer cells with medication. One or more drugs can be administered together. It is usually given orally, intramuscularly or intravenously. Giving chemotherapy directly into the cerebrospinal fluid is called “Intrathecal chemotherapy”.
Chemotherapy is usually administered in cycles and repeated every 21-28 days. It is decided whether the patient can receive chemotherapy or not, and if so, how many cycles it will take, based on the type of tumor, the age and general condition of the patient.
In cancer treatment, not only tumor cells but sometimes healthy cells can be destroyed as well. For this reason, most patients experience unpleasant side effects during treatment. Side effects; It depends on the type of treatment and the area being treated and may differ from person to person. The patient’s doctor chooses the treatment plan that will minimize side effects. These side effects usually end with the end of treatment.
During surgical treatment; Due to damage to normal brain tissue, weakness, coordination disorder, personality changes, speech and thinking difficulties may occur. Patients may experience seizures. Side effects worsen immediately after surgery, but disappear over the following days.
Radiotherapy in pediatric patients; It may cause learning difficulties, visual impairment, and growth and development retardation.
Major Brain Tumors
Glial tumors: Glial tumors constitute 45-50% of brain tumors. They consist of glial cells, which are the support cells of the brain. They infiltrate into the brain. Its borders are not clear. There may be different pathological types such as Astrocytoma, Glioblastoma, Oligodendroglioma, Ependymoma. Pathological staging is important in treatment. Glioblastomas (GBM) are among the most malignant tumors of the body. It constitutes 40-50% of all glial tumors. It is common in people aged 50-60. They show rapid growth.
Meningiomas: They constitute 20% of all intracranial tumors. They are most commonly seen between the ages of 40-60. It is twice as common in women. Meningiomas originate from spider-like structures called arachnoid structures. They are benign tumors. They show symptoms due to the effect of pressure. Location is important. Those located in the base and sensitive parts of the brain pose danger.
Pituitary Tumors: They constitute 5% of all intracranial tumors. They originate from the anterior lobe of the pituitary gland (neuropituitary tumors are rare) and are usually benign. It can cause headaches, visual field losses by compressing the optic nerve, effects of excessive hormone secretion, or endocrine disorders by suppressing the pituitary gland.
Nerve sheath tumors: They constitute 6% of all intracranial tumors. They originate from the nerve sheaths coming out of the brain. Vestibular schwannoma originates from the sheath of the vestibular (hearing-inner ear balance) nerve. It is benign. It is common in women. Headache, hearing loss, imbalance, facial numbness, pain, facial paralysis, paralysis in the opposite half of the body, difficulty in swallowing may occur.
Metastatic Tumors: They constitute 30% of all brain tumors. Any malignant tumor can metastasize to the brain. The most common malignant melanoma, AC, breast, colon and kidney cancers metastasize to the brain. 50% of metastases are multiple.
Risk Factors of Brain Tumors
Age: Although brain tumors can occur at any age, they are generally more common in adults and older ages. Some types of tumors are more common in childhood.
Chemical substances: Solvents, pesticides, petroleum by-products, toxic substances are known to increase the risk of brain tumor development.
Radiation: Exposure to high doses of radiation increases the risk of brain tumors.
Electromagnetic fields: Although long-term exposure to high electromagnetic effects such as high voltage lines, base stations, mobile phones, microwave ovens, etc. is thought to increase the risk of brain tumor formation, it has not yet been fully proven.
Genetic factors: It has been determined that some brain tumor types are associated with some genetically inherited diseases (such as neurofibromatosis, tuberous sclerosis, Von Hippell Lindau disease, Turcot syndrome, etc.).
N-Nitroso products: Products containing nitrite and nitrate found in some processed foods, cigarettes, some cosmetics, etc. are thought to pose a risk.
Infection, viruses and allergens: Viral agents such as Epstein-Barr virus and Cytomegalovirus have been identified to play a role in the formation of some brain tumors.