Brain cancer treatments in Germany
Glioblastoma is a malignant neoplasm that arises from glial cells of the brain. The tumor is heterogeneous and requires a differentiated therapeutic approach. When elaborating a treatment regimen, German oncologists take into account the molecular and genetic composition of the tumor, its location in relation to vital parts of the brain. The clinics in Germany offer innovative medical devices and drugs, thanks to which the doctors make maximum use of all therapeutic options. These include surgical resection and irradiation, chemotherapy, immunotherapy, therapy with tumor treating fields and experimental gene techniques.
Surgery and radiation therapy are the treatment basis
A surgical procedure is the first step in the comprehensive brain tumor treatment in Germany. The completeness of tumor removal determines largely the success of subsequent therapeutic stages. Glioblastoma can rarely be removed totally, since it has infiltrative growth and affects vital regions of the brain.
It is difficult to distinguish the tumor from healthy brain tissue by a naked eye, and therefore fluorescence-guided navigation with 5-aminolevulinic acid (5-ALA) is used during surgery. 5-ALA selectively accumulates in cancer cells and provides clear imaging of the glioblastoma growth boundary.
To increase the accuracy of neurosurgical procedures even more, the doctors use a stereotactic technique, which allows determining the tumor location in a 3D coordinate system using MRI. The surgery can be performed using an open method or minimally invasive catheter techniques (for example, laser ablation with the Visualase system).
Due to the elimination of the remaining cancer cells in the brain, radiation therapy consolidates the result of surgical treatment. The safest irradiation technique is the proton therapy. Proton therapy in Germany has less pronounced side effects compared to the conventional irradiation.
Supportive chemotherapy
As a rule, chemotherapy for brain cancer is not administered as a first-line option, since tumor cells mutate rapidly and become resistant to drugs. The indications for chemotherapy include:
- Surgical removal of more than 90% of the tumor volume
- Risk of relapse after the initial intervention
- Relapse of the disease (for slowing the disease progression)
Also, the doctors can administer chemotherapy drugs, namely temozolomide, if the surgical intervention is contraindicated. In this situation, the drug is administered orally. When chemotherapy complement surgery, the implant with the active substance is placed in the brain, near the tumor. This method of administration can improve the accuracy of the chemotherapy drug delivery, thereby allowing it to penetrate the blood-brain barrier.
Therapy with the tumor treating fields
In 2012, phase III of a randomized clinical trial was completed. This trial studied a fundamentally new method of treating brain cancer, namely the effect of tumor treating fields (TTF). The TTFs have been used in patients with recurrent glioblastoma who have not tolerated supportive chemotherapy. The study showed the same efficacy of TTF and chemotherapy, while TTF had a significant advantage due to the absence of toxicity and a higher quality of life.
In 2015, scientists received additional data on the increase in survival rates when using TTF, after which FDA, the reputable American organization, approved the use of the “Optune” device. The “Optune” and its analogues create an electric field around the neoplasm that suppresses multiplication of cancer cells. At the same time, the TTF technique guarantees absence of negative effects on healthy tissues.
Immunotherapy – updated information
Glioblastoma has traditionally been considered a “cold tumor”, that is, a type of brain cancer, in which immunotherapy is ineffective. However, the results of the 2019 studies showed an extension of the period of remission and the life expectancy of patients with neoadjuvant immunotherapy. The studies used monoclonal antibody preparations – pembrolizumab and nivolumab.
With neoadjuvant administration, monoclonal antibodies form the antitumor immunity during the active stage of treatment, when the tumor is not able to “mask” and suppress the immune system. As a result, the patient’s own T-lymphocytes can subsequently recognize and destroy cancer cells.
Prescription of immunotherapy is preceded by a mandatory genetic testing, since monoclonal antibodies have the best possible effect on the neoplasms with changed MAPK signaling pathways, while the tumors with PTEN mutations are more resistant.
Experimental gene therapies
Glioblastoma can be different in its histological structure and molecular genetic status. The large University Hospitals and Research Centers carry out genetic testing aimed at finding genes unique to all tumor types.
Such studies resulted in the creation of a MKNK2 hybrid gene. Normally, this gene provides the synthesis of two types of tumor proteins – MKNK2a, which inhibits the tumor growth, and MKNK2b, which stimulates the tumor growth. The MKNK2 hybrid gene shifts this balance towards the MKNK2a protein. As a result, glioblastoma either becomes smaller in size or disappears completely.
At the moment, the safety and effectiveness of the MKNK2 molecule is being studied in the laboratory, on a mouse model. Given the high rates in both parameters, one can hope that the technique will soon be used in people.