What are the side effects of immunotherapy

Immunotherapy

Immunotherapy is a relatively new form of cancer treatment that uses the multiple capabilities of the immune system in a number of ways to fight cancer cells.

Short version:

  • In addition to classic cancer treatments (e.g. surgical tumor removal, radiation therapy and / or chemotherapy), immunotherapy is now available to medicine in the fight against cancer.
  • Immunotherapy aims to bypass the cancer cells' evasive strategies and to direct the body's own immune system against the cancer.
  • The following forms of immunotherapy are currently available: treatment with monoclonal antibodies, vaccinations with tumor antigens, immunotherapy with "checkpoint inhibitors" and CAR-T-cell therapy.
  • With immunotherapies, cancer can be combated in a much more targeted manner and therefore usually has fewer side effects than conventional therapies.

So far, the classic treatments for cancer have included:

Today medicine has a fourth pillar in the fight against cancer - immunotherapy.

What role does the immune system play in the development of cancer?

Our immune system has the task of protecting our body from viruses, bacteria and other pathogens. The Immune cells (e.g. lymphocytes and other white blood cells) act like a kind of body's own police force and constantly migrate through our body via the bloodstream. They detect pathogens such as viruses, bacteria or damaged cells and eliminate them.

+++ More on the subject: The immune system - our body's own police +++

Form the second level of the defense system antibody (Protein bodies) produced by B lymphocytes and plasma cells. These antibodies can recognize pathogens or foreign cells based on certain structures on their cell surface (antigens), bind them and thus render them harmless. Today it is possible to artificially produce antibodies against various target structures on an industrial scale in laboratories and to use them for treatment. A typical example of this are vaccinations against influenza viruses, which lead to the formation of antibodies against the influenza pathogen and render them harmless upon contact.

In principle, antibodies also recognize recognition features of cancer cells (tumor antigens) and render them harmless. However, some cancer cells are able to camouflage themselves and protect themselves from the "attack" of the immune system. For example, they inhibit the immune system in its function or do not form suitable antigens to which the antibodies can dock. As a result, they escape the immune system ("Immunescape") and multiply unhindered, which facilitates cancer growth. This is exactly where immunotherapy comes in. It aims to bypass the cancer cells' evasion strategies and to direct the body's immune system against the cancer. There are different approaches to this.

What types of immunotherapy are there?

  • Treatment with monoclonal antibodies: These are genetically engineered protein bodies that bind to certain surface structures of tumor cells.
  • Vaccinations with tumor antigens or so-called dendritic cells, which present the tumor antigen particularly effectively to the other immune cells in order to recognize and attack the cancer. However, there is currently no corresponding drug available for treatment.
  • Immunotherapy with "checkpoint inhibitors": Immunotherapy with "checkpoint inhibitors" starts with the structures formed by the tumor, which inhibit the activity of defense cells against the tumor.
  • CAR T cell therapy: Defense cells (T cells) are taken from the patient and genetically engineered in the test tube with a "visual aid" (CAR-T receptor) with which the defense cells can recognize and attack the tumor cells.

+++ More on the topic: CAR T cell therapy +++

How does immunotherapy work and how is it carried out?

Immunotherapy with monoclonal antibodies

This form of immunotherapy, which is directed against structures on tumor cells, has been used successfully for lymph gland and breast cancer for more than 15 years. The aim of the treatment is to directly kill the tumor cells by the monoclonal antibodies or to offer the cells of the immune system a better point of attack for their "anti-cancer attacks". Immunotherapy with monoclonal antibodies is mainly carried out by intravenous infusions. Recently, new preparations have been introduced that allow administration under the skin (subcutaneously), which significantly simplifies the administration procedure for the therapist and for the patient. The injection time can thus be reduced to a few minutes.

Immunotherapy with checkpoint inhibitors

In principle, immunotherapy with checkpoint inhibitors is also carried out with the help of monoclonal antibodies. They bind and neutralize structures on the tumor cells, which hinder the immune defense like a "brake" pulled. By releasing these “brakes”, the immune cells can do their job and attack the tumor successfully. The administration of the immunotherapy with checkpoint inhibitors takes place via infusion, which takes between one and several hours depending on the preparation and tolerability.

+++ More on the topic: Immunotherapy with immune checkpoint inhibitors +++

Immunotherapy with CAR-T cells

This treatment takes several weeks, as sufficient T lymphocytes from the patient must first be obtained by cell separation (separation of the T cells from the blood). These T cells are sent to special laboratories. There they are genetically modified and provided with a receptor (CAR-T receptor; English "chimeric antigen receptor") against certain structures on the tumor cells. This is followed by the multiplication of the changed cells in the test tube. After the desired number has been reached, the cells are frozen and sent to the treatment center in this state. There they are thawed and given to the patient by infusion.

+++ More on the topic: CAR T cell therapy +++

Where are immunotherapies used?

Immunological therapeutic approaches are already used for the following cancers:

What side effects can I experience with immunotherapy with checkpoint inhibitors?

Since this form of cancer therapy affects the immune system, it can lead to an autoimmune reaction - i.e. an overreaction of the body against the body's own substances. Some of these complaints can be brought under control with medication. If this is not the case, patients must also expect an interruption or discontinuation of the cancer therapy.

The following side effects can occur with immunotherapy, among others:

What are the pros and cons of immunotherapy?

Immunotherapies open up a broad field for new therapeutic strategies in the fight against cancer. They can be used to combat cancer in a much more targeted manner and therefore usually have fewer side effects than conventional therapies such as chemotherapy. Another advantage is that immunological therapies are often effective in types of cancer and disease stages for which other therapeutic agents do not provide sufficient or no longer help. Treatment with the listed immunotherapies can lead to complete tumor control and to prolonging survival or healing.

However, the new immunotherapies are still very expensive. In Austria, however, the costs are covered by the health insurance companies. Another weak point of this therapy is currently that it cannot be used for every type of cancer and only some of the patients benefit from it. However, studies suggest that the combination with various forms of immunotherapy or conventional cancer therapies could lead to an improvement in the success of cancer treatment.

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Authors:
Tanja Unterberger, Bakk. phil.
Medical review:
Prim. Univ.Prof. Dr. Heinz Peter Ludwig
Editorial editing:
Mag. Julia Wild

Status of medical information:
swell

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