Living with and beyond cancer

Vulnerability to infection

The immune system is the body’s natural defence against infection. Cancer or its treatment can affect the way the immune system works. Having surgery can introduce an infection risk at the operation site. Chemotherapy and radiotherapy can weaken the immune system temporarily meaning that people having these treatments are more likely to catch infections for a while after each treatment and for a few months after treatment is completed. They may also find it more difficult to overcome the infection. In lymphoma or leukaemia the condition itself can reduce the effectiveness of the immune system, such that an infection that might be trivial to a healthy person can be debilitating and potentially life-threatening for someone with this type of cancer. For many people treated for cancer, their immune system recovers over time and their resistance to infection returns to normal, while others are left with a compromised immune system for the long-term.
Colds, flu and chest infections were common among people we interviewed but other types of infections also occurred. A woman who had lymphoma 11 years ago with complications including fluid in her lungs said she had had pneumonia twice within the last year. Fourteen years after having radiotherapy for penile cancer, a man still suffers with infections on his penis. A woman who had a colostomy for bowel cancer 16 years ago had occasional gut infections but irrigates her stoma regularly to reduce the likelihood of infection and to get rid of infections quickly when they occur. A woman who had ovarian cancer 7 years ago said that she tried to pace herself because if she did too much she went down with ‘every infection that was going’.
Some people said that an infection they had contracted after their cancer treatment had made them more ill or had a greater impact on them than the cancer and its treatment
In people who are vulnerable to infection due to a weakened immune system it is important to take steps to avoid contracting an infection, and to seek treatment quickly as soon as they suspect they are infected. People who have a weakened immune system as a result of cancer treatment are recommended to have a flu jab each year. Some people we spoke with said that they avoided public places or kept other people who had colds and infections at a distance; others took vitamin C supplements to try to strengthen their immune system. While some people said they went to their GP for antibiotics immediately they suspected they had caught an infection, others had been given a stock of antibiotics to take if the need arose.
The spleen plays an important part in the body’s immune system, and treatment for some types of cancer can include surgical removal of the spleen. Some people we spoke to had lost their spleen as part of treatment for lymphoma, leukaemia or pancreatic cancer, and had to take antibiotics every day to try to prevent themselves catching infections. People who have had their spleen removed, and some other people with cancer, are recommended to take antibiotics for the rest of their life, but Elaine, who has survived 14 years from a pancreatic cancer diagnosis, said she took them for just two years.

People whose cancer treatment includes a stem cell transplant from a donor are advised to repeat all their childhood immunisations and travel inoculations before going abroad.  

Last reviewed October 2018.

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