What is immunotherapy?
Immunotherapy uses our immune system to fight cancer. It works by helping the immune system recognise and attack cancer cells.
You might have immunotherapy on its own or with other cancer treatments. Immunotherapy is a standard treatment for some types of cancer. And it is in 
for other types of cancer.
There are different types of immunotherapy. We have information about the following types of immunotherapies:
- monoclonal antibodies (MABs)
- checkpoint inhibitors
- vaccines
- cytokines
- CAR T-cell therapy
Some types of immunotherapies are also called targeted treatments or biological therapies.
The immune system and immunotherapy
Our immune system works to protect the body against infection, illness and disease. It can also help protect us from the development of cancer.
The immune system includes the , and . Normally, it can spot and destroy faulty cells in the body, stopping cancer developing. But a cancer might develop when:
-
you have a low number of white blood cells so the immune system is too weak to be able to recognise and kill the cancer cells
-
the cancer cells produce signals that stop the immune system from attacking it
-
the cancer cells hide or escape from the immune system
Knowing this helps doctors understand and find ways to develop treatments. There are several different types of immunotherapy treatments. These work in different ways to help our immune system recognise and attack cancer cells.
Who has immunotherapy?
Whether you have immunotherapy depends on:
- the type of cancer you have
- how far your cancer has spread (the stage)
- other cancer treatments you’ve had
Testing
Before you have some types of immunotherapy you might need to have tests using some of your cancer cells or a blood sample. This is to find out whether the treatment is likely to work. These tests look for changes in certain proteins or .
Your cancer specialist can tell you if this applies to your treatment. This is not the case for all immunotherapies and you don’t always need this test.
To test your cancer cells, your specialist needs a sample (biopsy) of your cancer. They might be able to use some tissue from a biopsy or operation you have already had.
Types of immunotherapy
Immunotherapy treatments do not always fit easily into a certain type or group of treatments. This is because some drugs or treatments work in more than one way and belong to more than one group. So you might hear the same drug or treatment called different things.
For example, a type of immunotherapy called checkpoint inhibitors are also described as a monoclonal antibody or targeted treatment.
Ask your specialist about immunotherapy. They can explain:
- whether this treatment is suitable for you
- what the aim of treatment would be
- what it would involve and the side effects
Monoclonal antibodies (MABs)
Antibodies are found naturally in our blood and help us to fight infection. MAB therapies mimic natural antibodies but are made in a laboratory. Monoclonal means all one type. So each MAB therapy is a lot of copies of one type of antibody.
MABs recognise and attach to specific proteins on the surface of cancer cells. Many different MABs are available to treat cancer. They work in different ways and some work in more than one way. They might do one of the following:
- trigger the immune system
- help the immune system to attack cancer
Checkpoint inhibitors
Cancer can sometimes switch off the immune cells, so it isn't able to recognise and attack cancer cells. Checkpoint inhibitors are MABs that work by switching the immune system back on to recognise and attack cancer cells.
Checkpoint inhibitors stop the proteins on the cancer cells or T cells from pushing the stop button. This turns the immune system back on. The T cells are then able to grow and attack the cancer cells.
Vaccines to treat cancer
Vaccines can help the immune system to recognise and attack cancer cells.
In the same way that vaccines work against diseases, the vaccines are made to recognise proteins that are on particular cancer cells. This helps the immune system to recognise and attack those particular cancer cells.
Some people with melanoma skin cancer have a drug called talimogene laherparepvec (T-VEC). It’s a weakened form of the cold sore virus that has been changed in the laboratory. The changed virus grows in the cancer cells and destroys them. It also works by helping the immune system recognise and attack cancer cells.
Researchers are looking at other vaccines to help the immune system fight cancer.
Cytokines
Cytokines are a group of proteins in the body that play an important part in boosting the immune system.
Interferon is a type of cytokine found in the body. Scientists have developed man made version of this to treat a group of cancers called myeloproliferative disorders such as polycythaemia vera (PV) and essential thrombocythaemia (ET).
CAR T-cell therapy
This treatment changes the genes in a person’s to help them recognise and kill cancer cells. T cells are a type of white blood cell. Changing the T cell in this way is called genetically engineering the T cell.
It is available as a possible treatment for some people including children with leukaemia and some adults with lymphoma. People with other types of cancer might have it as part of a clinical trial.
