What causes brain tumors

Brain tumors

The therapy methods depend on the tissue type of the tumor, the age and general condition of the patient and the size and location of the tumor in the brain. In principle, the earlier a brain tumor is detected, the more favorable the prognosis for the patient. Depending on the WHO classification of the tumor, however, there is usually no cure, but symptom control, possibly with prolongation of survival and stabilization or reduction of the tumor size.

Three different therapy options can be used alone or in combination


Ideally, which occurs very rarely, the brain tumor can be surgically removed completely without leaving tumor cells behind. Often, however, it is only possible to remove a large part of the tumor. In some cases, e.g. if the general condition of the patient is poor or the tumor is in an unfavorable position, it may only be possible to take a small tissue sample (biopsy) to confirm the diagnosis.

Operation followed by radiation therapy with / without chemotherapy

Since in the vast majority of cases it is not possible to completely remove the tumor cells and an extensive operation would damage vital structures of the brain, follow-up treatment with radiation therapy and / or chemotherapy is advisable. Even if the tumor has been completely removed, follow-up treatment is advisable, depending on the WHO grade of the tumor

Radiation therapy as initial therapy

Radiation therapy as an initial therapy is used in particular when the tumor is at a particularly critical point in the brain and therefore only a biopsy and no operation is possible. The number of radiation sessions and the radiation intensity depend on the tissue type. During radiation therapy, side effects such as head pressure, headache, nausea, hair loss and possibly fatigue can occur. However, most side effects can often be alleviated with the use of various medications.

Mode of action of radiation therapy

Radiation therapy, like chemotherapy, aims to destroy cancer cells. A targeted concentration of radiation is intended to damage the cancer cells while sparing healthy tissue.

Since most tumors in the brain cannot be completely removed surgically, the remaining tumor cells should be destroyed by irradiation following surgical removal of the tumor or a biopsy. This is to prevent renewed local tumor growth or further tumor spread with recurrence of symptoms. For this reason, radiation therapy, which can often be carried out on an outpatient basis, is usually carried out after the operation of brain tumors.

Radiation can reduce the risk of tumor growth again. Radiation therapy can also be used in the case of advanced tumor diseases with large tumors or metastases, in this case in particular to control the symptoms and to relieve pain.


Chemotherapy alone, without surgery and radiation therapy, has little effect on most brain tumors. However, when used in combination with radiation therapy, chemotherapy can improve the effectiveness of radiation therapy. After the end of the irradiation, the chemotherapy can be continued with proven effectiveness in order to maintain and further improve the effect achieved up to that point (symptom control, size stabilization or size reduction). Even with the use of chemotherapy after radiation therapy, if this is no longer possible, e.g. in the event of a recurrence of a tumor, symptoms can be controlled through various substances and through various combinations, possibly with a response of the tumor (size stabilization or size reduction).

Recently, newer, well-tolerated substances have become available for the chemotherapy of brain tumors, for which it has been possible to show effectiveness in various tumors of the brain and for other tumors still has to be shown below. Since the effectiveness of many known and newly developed substances in the therapy of brain tumors is being investigated on the basis of new findings, it is generally advisable for patients with a brain tumor to have these tumor-specific therapies carried out by specialized doctors at "therapy centers" and, if possible, within "clinical studies" . Some of these therapies can be carried out on an outpatient basis.

In contrast to this, some tumors are treated: In children with medulloblastoma, chemotherapy is carried out up to the age of 4 after an operation, as the radiation exposure would be too great for the child's brain.

In the case of lymphoma, chemotherapy is used, which is followed by radiation therapy only in individual cases, depending on the response, in order to achieve a more effective effect.

Here, too, the therapy takes place within the framework of a strictly defined protocol.