How Dendritic Cell Therapy Can Extend Survival in Glioblastoma Patients
Glioblastomas are the most common and aggressive malignant brain tumors. Even when using combination treatment, the median survival rate of patients is 15 months. The efforts of scientists are therefore focused on the development of new techniques that would significantly improve treatment results.
Among these, dendritic cell therapy stands out as a highly promising approach. Emerging research demonstrates that dendritic cells in treatment of glioblastoma improvement in patient survival rates. They allow the patient’s immune system to attack the tumor more effectively, shrinking its size and blocking its further growth. Research shows a significant increase in patient survival with this immunotherapy option.
What is glioblastoma, and how is it treated?
Glioblastomas are highly invasive malignant tumors of the central nervous system. According to the 2021 World Health Organization classification, these are tumors of the fourth (highest) grade. Based on gene expression, they are divided into mesenchymal, proneural, neural, and classical subtypes.
Glioblastomas are not common, but these tumors do not respond well to treatment and often recur even after total removal.
Standard treatment involves surgical resection of the tumor, after which doctors conduct radiation therapy and chemotherapy. In developed countries, glioblastoma proton therapy is often used instead of conventional radiation therapy, which is considered safer for patients. Even this treatment provides patients with a two-year survival rate in 27.2% of cases.
The principle of dendritic cell therapy
Dendritic cells (DCs) are antigen-presenting cells that play a key role in the development of the T cell immune response. They are present in most tissues in an immature form. If DCs encounter antigens, they migrate to the lymph nodes where they demonstrate the antigen to T cells. They learn to recognize it and, as a result, attack the foreign agent, be it a tumor or an infection.
DC vaccination is an active cancer immunotherapy that was first used in 1996 for B-cell lymphoma. Patients are vaccinated with DCs loaded with tumor-associated antigens. These DCs initiate an anti-tumor T cell response, selectively destroying tumor cells and preventing cancer recurrence through immunological memory.
The treatment process involves harvesting immune cells from a person’s blood, treating them with antigens, and then injecting them into the body again. They send information about tumor antigens to T cells. As a result, they begin to attack the tumor. The injections are repeated several times.
So far, only one DC-based vaccine has been used as a standard treatment. It is Provenge, a prostate cancer drug. There are also hundreds of drugs that are being used as part of clinical trials, including those assessing the effectiveness of DCs for glioblastomas.
How effective are DCs for glioblastomas?
Liau et al. first used DCs for glioblastomas in 2000. A patient with recurrent glioblastoma received the vaccine. Although the immune response was activated, there was no objective response to treatment. Since then, the immunotherapy technique has been improved. Numerous studies assessing its effectiveness in glioblastoma treatment have already been published, including six randomized ones. A large number of clinical trials are still ongoing, and their results will be published soon.
Based on the results of the completed studies, glioblastoma immunotherapy is more effective when administered after total tumor resection. This is due to the fact that the microenvironment of glioblastoma depresses the immune response. However, the small residual tumor remains unprotected against attacking T cells.
In the studies, treatment of glioblastoma with DCs was used in different cases, including:
- After surgery
- After radiation therapy and chemotherapy
- As monotherapy (the sole treatment method)
When patients developed an immune response after DC injection, improved treatment outcomes were achieved. For example, in the Wheeler et al. study, the two-year survival rate in the immune response group reached 56%, while in the non-response group it was only 8%.
Randomized trials have shown that DC vaccination increases the median survival rate by 30-50%. Additionally, the use of dendritic cells increases progression-free survival.
The most successful study was carried out by Batich et al. The DC vaccination extended the median survival to 41.1 months, compared to 18.5 months in the control group. One-third of patients survived more than 5 years after the completion of treatment, which is an excellent result considering the high grade of brain tumors.
All studies found that DC vaccination was well tolerated. Severe side effects are very rare. Some patients developed cerebral edema due to inflammation caused by the immune response, but it was controlled with glucocorticoids. Additionally, flu-like symptoms and lymph node inflammation were observed in some cases.
Where can I undergo treatment?
You can undergo treatment abroad. You are welcome to use the Booking Health service. The best glioblastoma treatment centers are presented here. Some of them already perform immunotherapy for brain tumors with dendritic cells.
The Booking Health website lists the current glioblastoma immunotherapy cost. You can sort hospitals and compare prices. The Booking Health specialists will help you select a hospital and arrange your trip abroad. When booked through this service, treatment will cost you less due to the absence of additional fees for foreign patients.