What is immunosuppression?
What you need to know:
- Your immune system protects you from infection.
- Blood cancer and its treatment can weaken your immune system – this is called immunosuppression or being immunosuppressed.
- Ask your hospital team whether you are immunosuppressed and whether this is likely to change.
Understanding your immune system
Your immune system is a network of cells, tissues and organs that work together to protect you from infection. White blood cells play a particularly important role, killing germs that could cause you harm.
Blood cancer often affects parts of your immune system, especially white blood cells. This makes you more vulnerable to infection. The medical word for this is immunosuppression, or immunocompromise.
People with blood cancer can get more infections than normal. Infections might last longer and develop more quickly. They may be more serious than normal.
It is important to know that you may be at higher risk from infection if you have blood cancer. The level of risk varies – it depends how the blood cancer is affecting you at a particular time. It is normally highest while you are having treatment.
Ask your hospital team or GP whether you are immunosuppressed.
Read our information about infection and who is at risk.
How blood cancer causes immunosuppression
There are several ways that blood cancer causes immunosuppression:
- It can affect your bone marrow, so it can’t make enough healthy white blood cells.
- Your white blood cells may develop abnormally and not work properly.
- Cancerous blood cells can build up in your lymph nodes (glands) which are an important part of your immune system.
- Active treatment for blood cancer can lower the number of white blood cells in your blood.
I can't be overly careful
"I have blood tests every month and I haven't been neutropenic since my stem cell transplant. So I'm reassured by the fact that I do have some sort of immune system.
I can't really be overly careful about it because I work with kids."
David, diagnosed with myeloma
Blood cancer treatment and immunosuppression
Nearly all treatments for blood cancer can cause immunosuppression. This is usually temporary. Your immune system should get stronger when the treatment stops, although this may happen gradually.
Some people will stay in hospital for their blood cancer treatment. Some will have treatment as an outpatient and go home in between doses. Others will have their treatment entirely at home.
- If you are staying in hospital, always tell staff if you feel unwell so you can get treatment for an infection if you need it.
- If you are at home, make sure you and the people close to you know the symptoms of infection and how to get medical help.
As well as killing abnormal white blood cells, chemotherapy can lower the number of healthy white blood cells in your blood.
The risk of infection is highest around one to two weeks after having chemotherapy. After that, your white blood cell count should start to go up again.
It may take time to get back for your white blood cell count to get back to normal levels after you have finished treatment with chemotherapy.
Targeted therapies specifically target cancer cells. They are less likely to lower your level of healthy white blood cells, but some do. It depends on the specific drug you are taking.
Many drugs are classed as targeted therapies, including inhibitors (for example, imatinib, bortezomib and venetoclax), monoclonal antibodies (such as rituximab and daratumumab), immunomodulators (for example, thalidomide and lenalidomide).
Ask your hospital team about your targeted treatment and how it will affect your immune system.
Radiotherapy doesn’t usually affect your white blood cells significantly if it is given to a specific area of the body (local radiotherapy).
If you have radiotherapy to your whole body (total body irradiation) before a stem cell transplant, your immune system will be affected, but should recover after a while.
Steroids can cause a higher risk of infection so you may need to be more careful if you are taking them as part of your treatment. Ask your hospital team for advice.
If you are having a stem cell transplant, you will have treatment with chemotherapy before the transplant. This destroys abnormal blood cells but also healthy ones. So your immune system will be weak.
It can take several days for the newly transplanted stem cells to start producing white blood cells. This is called the graft. At this point your immunity will be very low.
After the graft, your immunity should start to improve, although it may take some time to recover fully.
CAR T-cell therapy can affect healthy white blood cells called B cells as well as killing abnormal ones. This one way it weakens your immune system.
To help with this, you are likely to be given preventive antibiotics for an extended time. Your hospital team may also give you antibody treatments. Antibodies play an important role in fighting infection.
How will my treatment affect me?
If you are having any treatment for blood cancer, ask your hospital team:
- How will my treatment affect my immune system?
- Will my immune system recover?
- How long will it take to recover?
If you are not having treatment, ask your hospital team or GP:
- Am I immunosuppressed?
- How is this likely to affect my daily life?
- Will this change?
There are things you can do to protect yourself if you are immunosuppressed. Read our information about general hygiene and food safety, and our frequently asked questions about specific activities.