Despite intensive research, the causes of central nervous system tumours are still largely unknown. Most patients develop this type of tumour without apparent contributing factors. The widely discussed suspicion that electromagnetic fields, from mobile telephones or power lines for instance, could be responsible for causing brain tumours was not confirmed in several studies.

The answer to the question whether gliomas are hereditary is negative for most patients. Even though there are very rare cases of hereditary tumours these were caused by known hereditary genetic syndromes such as Turcot’s syndrome or Li-Fraumeni syndrome. In medicine, a syndrome is a group of different symptoms that occur consistently together.

The cause of these is usually more or less known or can be suspected at the very least. The origin and development of the disease, however remains unknown.  The word syndrome is often used when the symptoms are at least to some extent consistent and similar in comparable cases.

Neurological disorders or functional impairment often mean that patients cannot continue with their usual day-to-day lives. Intensive rehabilitation measures including speech and occupational therapy can have positive results for patients when they have to re-learn certain body functions, how to speak and train their memory.

A healthy diet lowers the risk of developing cancer and prevents recurrence after overcoming the disease. It provides patients with important protective substances that can have a positive impact on the course of the disease and boost the immune system.

Experts assume across the board that glioma patients will not be able to drive temporarily. These patients should urgently consult their doctors before taking up driving again so as not to jeopardise their insurance in case of an accident.

If patients’ limitations are of such an extent that they can no longer work, an application for early retirement may be possible. Many brain-tumour patients, however find it helpful to continue working. It takes their mind off the disease and gives them a feeling of being needed.

If a brain tumour is suspected, after taking a detailed history treating physicians have several different diagnostic methods at their disposal:

• Neurological exam
• The patient’s history in combination with a thorough physical exam can already provide physicians with initial clues as to a tumour in the brain.
• Computer tomography

The brain is screened with the help of x-rays and visualised in cross sections. This allows physicians to detect tumours, calcifications and bleeding.

Magnetic resonance imaging
Magnetic resonance imaging (MRI) is a radiological procedure during which high-contrast cross sections in an excellent resolution and any slice orientation desired can be taken. This radiation-free technique is based on the magnetic properties of tissue, in particular that of tissue water. As their hydrogen content often differs it is possible to differentiate between tissue with mutations and normal tissue.

Abnormalities in the brain can be visualised in greater detail than with a CT scan. An MRI is usually recommended after the CT scan has resulted in a suspicious finding, or in no finding even though there was a reasonable case for suspicion.

An MRI not only allows for the imaging of the body in any slice orientation desired, it also offers a great variety of contrasts. This is useful for differentiating between different types of tissue and between malignant changes and healthy tissue. In some cases an MR contrast agent is used to allow for even sharper contrasts.

Magnetic resonance spectroscopy (MRS)
can determine metabolic products and metabolic processes in the brain, such as glucose, neurotransmitters or their metabolites. In this, the substance is identified by its individual pattern. Like a fingerprint, this pattern is unique to every molecule. On the respective spectrum, every peak can be matched to a specific molecule.

PET (Positron emission tomography)
This technique is used to visualise metabolic processes in the body. Patients are given glucose labelled with a radioactive tracer before the examination. The body breaks down the glucose, which leaves a trace thanks to the radioactive substance. The special imaging technique of the PET visualises that trace. As malignant tumours have greater metabolic activity than healthy tissue they stand out in the PET image.

SPECT (Single Photon Emission Computed Tomography)
Single Photon Emission Computed Tomography (SPECT) is an examination technique to visualise the metabolism of different organs in an image. This is made possible by using radioactive substances (tracers) that are injected into the patient before the examination. These are distributed throughout the body and accumulate in the organ to be examined. A special camera then measures the radiation emitted by the tissue. The results are added back together to form a three-dimensional image.

The most important aspects when selecting a treatment for gliomas in the brain are the patient’s condition and the tumour’s location.

Different treatment methods are available:

1. Surgery
2. Radiation
3. Chemotherapy

1. Surgery 
Surgery is the most important treatment option and the first step of the therapy. Only very few gliomas are inoperable due to their location in the brain.

The aim of surgical resection of a glioma is to reduce the tumour mass as much as possible. This can improve the patient’s quality of life. Removing as much of the brain tumour as possible, a so-called complete resection, ensures that concomitant treatments such as a subsequent chemotherapy are more effective.

Physicians decide on surgery if the tumour is well-accessible and resectable with the techniques and instruments available, and if the patient’s overall condition allows for an operation. In order to safely remove as much of the tumour mass as possible, this type of resection is partly performed as an awake surgery. This allows surgeons to perform the best possible resection at the lowest possible risk.

Biopsy
A biopsy is the extraction of tissue. The tissue is then examined for malignant changes under a microscope. Further insights on the type and characteristics of the tumour cells are gained in this way.

Follow-up
Three to seven days after surgery, most of the patients take cortisone; the dose is reduced gradually depending on the clinical and radiological findings. Depending on the histological results, additional treatments such as radiation therapy and chemotherapy are administered subsequently.

2. Radiation therapy
Often, surgery alone is not enough to remove the tumour entirely without microscopic residual tumour tissue remaining. In a lot of cases brain tumours grow into the surrounding brain tissue. Those cell clusters cannot be detected with the naked eye before or during surgery or using imaging techniques. Radiation attempts to inhibit residual cells from growing or to remove visible tumour tissue. For this, a certain dose of radiation is needed, which can be higher or lower depending on the type and size of the tumour, the surrounding normal, healthy tissue and the individual disease character. Treatment can last over a longer period of several weeks. The effects and side effects in need of treatment, are mostly limited to the radiated body region.

To keep radiation therapy as gentle as possible, it is administered fractionally in the vast majority of cases, i.e. small amounts of the total dose are given every day. This achieves damage to the tumour cells and better protection of the surrounding normal and healthy tissue. The exact individual dose and total dose and the size of the radiated area depend on the type and extent of the cancer.

3. Chemotherapy
Chemotherapeutic medicinal products are used to destroy tumour cells or prevent them from growing further.
Depending on the type of tumour, different chemotherapeutic agents, also called cytostatics, are used alone or in combination.
Chemotherapy always strives to achieve the strongest possible effect on the tumour while protecting healthy tissue as far as possible.

There are different types of cytostatic (inhibiting cell division) medicinal products. The substances used most commonly in the treatment of glioma include temozolomide, lomustine, bevacizumab/irinotecan, carmustine, procarbazine and vincristine. Substances such as carboplatin, cisplatin and methotrexate are used relatively rarely. Currently, many new substances are being investigated in a number of studies.

These substances mainly have an effect on the control centre of the cell, the cell nucleus. There, they cause damage to the hereditary molecule, the DNA (deoxyribonucleic acid). As a result, the cell either dies or becomes unable to divide.

As opposed to surgery and radiation, medicinal products have the advantage of allowing for systematic treatment, i.e. treatment of the whole body. Given as an infusion, a tablet or with a syringe, the cytostatics are distributed by the bloodstream to all tissue and organs in the body, thereby reaching and destroying even “hidden” tumour cells. An exception to this is the brain, which can only be reached by certain cytostatics.

Chemotherapy is given in several cycles: Usually, the medicinal products are administered over one to five days. This is followed by a rest period to allow the healthy tissue and organs of the body, for example the bone marrow or the gastrointestinal mucosa to recover from the cell-damaging effects of the cytostatics.
Most cytostatics are injected or given over a “drip” (infusion). Some of the medicinal product can be taken by mouth in the form of tablets.