Immunotherapy: Information and Immunotherapy Specialists

The use of immunotherapy to fight cancer is also known in medical terms as immuno-oncology.

The human immune system is very effective at fighting foreign and harmful cells. As a rule, it also recognizes and fights cancer cells. Under certain circumstances, however, this natural self-healing mechanism may no longer function properly.

This happens, for example, when tumor cells and their surface markers have undergone significant changes. The immune cells can then no longer recognize them. Cancer cells can also produce defense molecules that signal to the immune system that they are harmless. This allows them to evade the immune system.

In both cases, the immune system no longer responds to the malignant cancer cells, and the tumor is able to grow.

The goal of immunotherapy is to show the immune system which cells it needs to destroy. This allows the body to fight the cancer on its own.

Checkpoint inhibitors

Checkpoint inhibitors are antibodies. They block certain communication signals between a cancer cell and an immune cell. Most often, these are signals that allow the cancer cell to deactivate immune cells and thus evade the immune response.

The best-known examples here are the PD-1/PD-L1 system and CTLA-4 as surface molecules. Antibodies that act as PD-1 inhibitors, for example, block a tumor’s ability to suppress immune cells. This allows the immune cells to remain active and attack the cancer cells.

Checkpoint inhibitors are currently approved for the following cancers:

• Malignant melanoma (black skin cancer),
• lung cancer,
• Renal cell carcinoma,
• Osteosarcoma,
• Hodgkin lymphoma,
• Bladder cancer (as adjuvant therapy—that is, after cancer surgery—since April 2022),
• head and neck tumors.

However, some approvals are contingent on patients having what is known as PD-1-positive status. This means that patients must have certain surface molecules on their tumor cells. Only then can the immune system respond positively to checkpoint inhibition.

The use of immunotherapy with checkpoint inhibitors is evaluated on a case-by-case basis for each patient. It also depends on any prior treatments.

CAR-T Cell Therapy

In CAR-T cell therapy, T cells are harvested from the patient and genetically modified outside the body. The cells are equipped with an artificial T-cell receptor. This allows them to bind to very specific tumor cells in the patient’s body, thereby triggering an immune response. The patient then receives the modified CAR-T cells back in the form of a “medication.”

These new T-cells enable the immune system to recognize and fight the malignant cancer cells.

Cytokines

Cytokines are one of the best-known immunotherapies in oncology. Cytokines are small, hormone-like molecules. They are exchanged between immune cells to transmit information or regulate the cells’ activity.

Adding certain cytokines can enhance the immune response, for example, against cancer cells.   

One area of research within oncology that is currently being actively pursued is cancer vaccination. In principle, this works much like a flu shot. The immune system is prepared in advance to fight specific cells.

In the case of a tumor, antibodies bind to specific surface molecules on the tumor. Like a beacon, they attract additional immune cells, which then destroy the cancer cells.

Such a vaccine has been used successfully for years. STIKO recommends vaccination against human papillomaviruses (HPV) for boys and girls between the ages of 9 and 17. It prevents infections with tumor-causing HPVs, which are responsible, among other things, for

• cervical cancer,
• penile cancer,
• anal cancer, and
• oral and throat cancers

.

As the name suggests, immunotherapies influence the human immune system. Effects on a variety of other immune responses cannot be ruled out. The immune response is activated, and important control mechanisms are temporarily suspended. For example, the immune system may overreact and damage healthy tissue as well.

Typical symptoms include flu-like symptoms such as

• fever,
• headaches and body aches,
• chills,
• fatigue, or
• fatigue.

However, it can also lead to

• edema (fluid buildup in the tissues),
• diarrhea, or
• an increased susceptibility to infections

.

Very rarely, severe allergic or inflammation-mediated side effects may also occur. In isolated cases, these have already led to fatalities. 

Immuno-oncology offers certain patients an additional treatment option. However, immunotherapy is not a cure-all for cancer. Its effectiveness depends heavily

• on the individual condition of the patient,
• the specific tumor, and also
• on any prior treatments the patient may have already undergone

.

Immunotherapies cause fewer and less severe side effects than conventional cancer treatments, such as radiation therapy or chemotherapy.

In most cases, immunotherapies are also more specifically effective against cancer than chemotherapy. Chemotherapy always damages healthy cells and tissues as well.

Immunotherapies are now routinely used at specialized oncology centers and university hospitals. At these facilities, specialized physicians can monitor the treatments and provide outpatient care for patients. 

Due to the wide range of oncological diseases, a variety of medical disciplines are involved. These include, among others, 

• neurology,
• hematology,
• urology,
• gynecology,
• pulmonology,
• Psycho-oncology,
• Palliative Care,
• Radiology, and
• Surgery.