This Article, What is a Brain Tumor? New growths of the brain and the surrounding meninges (meninges) are called Brain tumor. These may be benign or malignant and are also referred to as brain or primary brain tumors.
Brain metastases can also occur in the brain. These are secondary tumors of cancers that originate outside the brain (for example, breast or lung cancer). They are therefore not among the primary brain tumors but are called secondary brain tumors.
With about ten new cases per 100,000 inhabitants annually, brain tumors are among the rarer tumors. They occur preferably between the ages of 40 and 75 years. In childhood, malignant neoplasms of the brain are the second most common cancer after leukemia (blood cancer).
Different Areas of the Brain for Different Tasks
The interplay of different brain centers allows memory, learning, sensory and motor skills. Functionally, the brain is divided into three important areas: the cerebrum, cerebellum, and brainstem.
The cerebrum is the largest part of our brain. Here the mental work including movement, language, and eyesight is coordinated.
The cerebellum is the second largest part of the brain. His main tasks are the coordination of the conscious muscle functions, the control of the balance in walking and the coordination of the language.
The brain stem contains vital centers for the regulation of the so-called vital functions such as breathing, heartbeat and body temperature.
Brain Tumors Come From Different Cell Types
The classification of brain tumors is based on developmental aspects or on the cell type from which they emerge. The brain contains tumors that can arise from the following tissues:
Nervous tissue (gliomas: the most common brain tumors, including astrocytoma, glioblastoma, oligodendroglioma, medulloblastoma, and ependymoma).
The Meninges (Meningiomas)
The Non-Developed Embryonic Tissue (Germ Cell Tumors)
The Hormone-Producing Pituitary Gland
Other malignant Tumors in the Body, For Example, Breast Tumors (Metastases)
Classification of Brain Tumors
The brain tumors can be benign or malignant. Benign brain tumors grow slowly and in most cases remain well differentiated from adjacent, healthy brain tissue. Malignant brain tumors often grow larger rapidly, forming metastases and growing destructively into the surrounding tissue (so-called infiltrative growth).
The malignancy of the tumors is divided into different degrees. The most widespread classification of brain tumors is that of the World Health Organization (WHO classification). It provides for four different tumor grades. The subdivision is based on the type of cell from which the brain tumor has developed. In the so-called neuropathological examination, the cells of a tissue sample from the tumor are examined closely in order to be able to classify the brain tumor diagnostically.
The WHO Grading of Brain Tumors is:
WHO Grade I (Benign)
WHO Grade II (Still Benign)
WHO Grade III (Already Malignant)
WHO Grade IV (Vicious)
WHO grade I correspond to a slow-growing, very benign tumor with a favorable prognosis, while WHO grade IV is a fast-growing, particularly malignant tumor with an unfavorable prognosis.
This distinction is important with regard to the therapy to be initiated, the course to be expected and the success of the treatment.
Which are the Most Common Tumors?
With about 50 percent of all brain tumor primary tumors, gliomas are the most common brain tumors. Gliomas can be subdivided into different subgroups. Astrocytomas are the most common glioma and can occur in all four WHO grades. They occur a little more often in men and develop within a few weeks to months. Glioblastoma (Glioblastoma multiforme - WHO grade IV) is a particularly malignant form of glioma.
Medulloblastoma is the most common brain tumor at the age of seven to 14 years, accounting for 20%. Somewhat more often, boys are affected. Vomiting in the morning, severe headaches, and disturbances of the coordination (for example, gait uncertainties) can be first indications. Although medulloblastoma is one of the most malignant tumors, its healing prospects are relatively good. An attempt is made to completely remove the tumor surgically. This is followed by radiation of the head and, if necessary, chemotherapy.
Meningiomas develop from cells of the brain membranes. They account for about 20 percent of all tumors inside the skull; Most affected are middle-aged and older adults and more women than men. Meningiomas grow slowly. Therefore, they often remain undetected for a long time or are only found by chance. In 85 percent of cases, meningiomas are classified as benign tumors in WHO grade I. They can be cured by surgical removal.
However, about ten percent of meningiomas are so-called atypical meningiomas (WHO grade II), which are growing and have a tendency to return after treatment (recurrence). But even for these meningiomas, a favorable prognosis is generally valid. Malignant meningiomas with WHO grade III is only seen in about five percent of those affected. They usually require additional radiation.
What are the Causes of a Brain Tumor?
The exact cause for the development of brain tumors is unclear. However, a number of factors such as cancer-causing viruses and substances (oncogenes) or a hereditary (genetic) bias may possibly benefit them.
What are the Symptoms of a Brain Tumor?
The first signs of a brain Tumor can be manifold. Possible are:
Seizures (epileptic seizures): the most important early symptom. If seizures occur for the first time between the ages of 25 and 60, brain tumors are the most common cause.
Headaches that worsen when bending, straightening or pressing
Behavioral and essential changes such as irritability, forgetfulness, listlessness and uncontrolled tantrums
Later, depending on the area of the brain in which the tumor grows, the following symptoms may occur:
Speech and Smell Disorders
Nausea and Vomiting
Visual Disturbances such as Blurred Vision, Defaults in the Field of Vision
Numbness
Paralysis and Difficulty in Coordinating Movements
On the one hand, the symptoms are caused by the displacement of the intact brain tissue by the growing tumor and, on the other hand, by the destruction of the tissue in and around the tumor. Some tumors grow quickly and symptoms appear after days or weeks. Others grow over years and are barely noticeable.
How is a Brain Tumor Detected?
After a conversation with the doctor, a physical and intensive neurological examination is carried out. The doctor checks, among other things, reflexes, balance, muscle strength and sense of touch.
Further Investigations which are carried out are:
Electroencephalogram (EEG, Measurement of Brainwaves)
X-rays of the Head
Computed Tomography of the Head (CT) and/or Magnetic Resonance Imaging (MRI, NMR)
Optionally, a tissue sample (biopsy) from the tumor through a small hole drilled in the skull under local anesthesia (stereotactic biopsy) to determine the tumor type
Laboratory Examination of Cerebral Water (CSF)
Also, the examination of the ocular fundus (ophthalmoscopy) is a common diagnostic method in suspected brain tumor and can provide information about a possible brain tumor.
What Treatment Options are there?
The treatment of a brain tumor depends on its nature and its malignancy. The goal of therapy is to cure the patient or, if that is not possible, at least to reduce the size of the tumor and alleviate symptoms.
The Following Therapy Options are available:
The Operation
Typically, the tumor is removed through an opening of the skull while the patient is anesthetized. Lately, the so-called endoscopic operations are on the rise, the skull does not have to be opened, but only operated through a small hole.
The operation also carries risks. Blood vessels, nerves, and brain substance can be damaged. On the other hand, surgery can be life-saving if the brain no longer has enough space through the tumor. In some cases, the tumor is so unfavorable that its surgical removal is not possible.
The Radiotherapy
In non-operable tumors, but also in combination with surgery, the tumor cells can be destroyed by X-rays. Healthy cells, on the other hand, recover faster because of better repair mechanisms. However, as the healthy tissue is affected, it can cause side effects such as tiredness, vomiting, diarrhea, inflammation of the mucous membranes and headache. But medications can relieve these symptoms.
A combination of surgery and radiation is also possible. Benefits include a short treatment time and relatively few side effects.
Radiosurgery
In this form of high-precision radiotherapy, the patient's head is fixed by a helmet, whose small openings direct a very high dose of radiation to the target to destroy the tumor. Experts call this "stereotactic one-time radiation". More than 200 individual Telecobalt sources produce a radiation beam with the smallest diameter. The bundles cross at one point. Bundling can be achieved through the special helmet mentioned.
The biological effect of the high single dose used to irradiate the tumor in this method of treatment is much greater than with conventional radiotherapy, which is distributed over many small single doses. Thus, with the "radiometer", benign and malignant tumors in the head can usually be removed on an outpatient basis with a single irradiation, even with multiple metastases.
Lengthy rehabilitation measures and associated work breaks are not necessary with this form of therapy.
Chemotherapy
In chemotherapy, prescribed drugs are used to kill the malignant tumor cells, while the healthy cells in the body get away relatively unscathed. For example, according to one scheme, the drug is taken for four days and then paused for two weeks. This process can then be performed three times and more frequently.
Most chemotherapeutic agents used in brain tumor therapy directly damage the genetic material (DNA) of tumor cells. Examples are nitrosoureas (ACNU (Nimustin), BCNU (carmustine) and CCNU (lomustine)), temozolomide and procarbazine.
Other substances have a disruptive effect on the metabolism of the tumor cells, especially on the metabolic processes that are important for the formation of new genetic information (DNA). Examples include methotrexate (MTX) and cytarabine (Ara-c).
Side effects include an increased risk of infection and bleeding, nausea, vomiting and general fatigue and hair loss.
Further Treatment Measures
The tumor, as well as the treatment, can lead to cerebral edema (accumulation of water in the brain tissue). This is improved by the administration of cortisone. Very effective painkillers help against pain.
Pastoral care for Patients and Their Relatives
It is important that the patient is accompanied and supported by relatives and friends on his path of illness and treatment. Brain tumors are treatable diseases. In many cases, effective help is possible and often a cure. The prognosis of some brain tumors is still very bad. Self-help groups, psychologists, and pastors can assist the patients and their relatives.
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