Radiotherapy in Brain Tumors
Radiotherapy in Brain Tumors, In most cases, the operation provides the first therapeutic step with removal of the visible tumor or also for relief, in order to reduce present ailments. In the case of tumors in the region of the posterior cranial fossa, this also affects the pressure on the brain stem and the internal cerebral waterways. In addition, surgery provides the necessary opportunity to gain tumor tissue, which can be characterized in the laboratory. The subgroups of the brain tumors, which are necessary for a subsequent therapy decision, can be identified. For example, tumors that infiltrate the sensitive brain stem or important brain regions that function in the brain are frequently not resectable.
Often, however, the operation is not capable of reliably removing the tumor without leaving microscopic residual tumor tissue. Brain tumors often have the property of infiltrating into the surrounding brain tissue without the possibility of discovering these cell structures with the naked eye during the operation or before the operation with the aid of imaging methods. More extensive operations with the aim of removing these possible cell clusters are usually impossible, since otherwise unacceptable neurological deficits would be caused.
In these situations, the essential aim of the irradiation is to prevent any remaining cell aggregates from further growth, or else to remove visible tumor tissue, which is surgically not completely removable due to the localization, or to treat it in such a way that it does not grow any further.
As a result, in most cases the need for radiation treatment of the so-called “extended tumor region” results. This means that only the area of the original tumor seat and areas of possible tumor infiltration are irradiated by radiotherapy.
Other tumors of the central nervous system, predominantly located in the posterior cranial fossa, show a special tendency to spread tumor cells across the cerebral water passages. These scatterings can occur in the brain, but also in the spinal cord channel. Scatterings of this type can not be surgically prevented. Radiation therapy is able to detect these areas of the central nervous system sufficiently. A sophisticated therapy technique is used.