There are many ideas about what causes childhood cancer but no definite answer. Many scientists believe that the most likely reason is simply chance e.g. being born with a faulty gene. As we get older many external factors can increase the risk of cancer including: smoking, not doing enough exercise and a bad diet. Adults are more likely to be affected by these things because they've been in contact with them for longer, but it's very unlikely that these would cause cancer in younger people.
Children and young people with cancer aged 0–18 are treated in specialist treatment centres. Often these are many miles from where they live, though they may receive some care closer to home. When a child or young person is diagnosed with cancer, their medical team puts together an individual treatment plan that takes into account:
- the type of cancer they have
- its stage (such as how big the tumour is or how far it has spread)
- their general health.
The three main ways to treat cancer are:
A treatment plan may include just one of these treatments, or a combination. Children and young people may be in hospital for long periods of time, or they may have short stays and be out of hospital quite a bit. It depends on the type of cancer, their treatment and how their body reacts to treatment.
Some can attend school while treatment continues. When cancer is under control, or in remission, children and young people usually feel well and rarely show signs of being unwell. If cancer comes back after a period of remission, this is known as relapse.
This is when medicines are used to kill off cancer cells. The doctor may use one medicine or a combination. These are usually given by injection into the bloodstream (intravenously). Sometimes they are given by other types of injection or as a liquid or tablet.
Chemotherapy is usually given in cycles. This means having several days or weeks of treatment, then a rest period, and so on. Usually children and young people don't need to stay in hospital and can go home, and often back to school, between cycles.
This uses high-energy X-rays, which are directed at the site of the cancer to kill the cancer cells, while doing as little harm as possible to healthy cells. Radiotherapy doesn't hurt, and it only lasts a few minutes, but it's important to stay very still during the treatment. It is usually given Monday to Friday, with breaks at the weekends.
Proton beam therapy is a special type of radiotherapy that can be used to treat some types of cancer. This type of treatment isn't available in the UK yet, but is sometimes offered abroad, if appropriate.
Many childhood cancers are treated with surgery. Chemotherapy or radiotherapy may be given first to shrink a tumour and increase the chances of successful surgery. Chemotherapy or radiotherapy may also be given after surgery if the cancer hasn't been completely removed or to make sure it's all gone.
Stem cell transplant
This treatment is mainly used for leukaemia but can also be used for other cancers. A stem cell transplant is usually carried out after a child or young person's stem cells have been destroyed through high doses of chemotherapy or radiotherapy. Replacement stem cells are put in through a drip. The child or young person's immune system will be very weak at this time. They will be strictly monitored in hospital for a few weeks and visitors will be restricted until their immune system has recovered.
Different cancer treatments can cause different side effects. Which ones a child or young person experiences depends on their cancer and treatment. Below is some information about some of the side effects children and young people having cancer treatment may experience.
Feeling and being sick
Chemotherapy and radiotherapy can both cause nausea, and chemotherapy can also cause vomiting. Sometimes anti-sickness medicines, called anti-emetics, are given to help relieve this. Problems with nausea and vomiting should be resolved before the child or young person returns to school.
Both chemotherapy and radiotherapy can cause significant tiredness during treatment and for several months afterwards. This can affect mood as well as energy levels. Fatigue can make it harder for children and young people to concentrate and rest is important. Cancer and its treatment also often cause sleeping problems.
Although chemotherapy kills cancer cells, it can kill other fast-growing cells too, including hair cells. This means that chemotherapy can make hair fall out including eyebrows, eyelashes and body hair.
With radiotherapy, hair loss only happens to the area that's treated. Hair usually grows back once treatment has finished, though it may not grow back in an area targeted by radiotherapy. Hair can look different when it grows back, and it might be curlier, finer, or a different colour.
Treatment can cause changes in appetite and weight, as well as other side effects, such as a sore mouth. It can also affect eating habits and can cause increased hunger or a loss of appetite, weight gain or loss. Some children may return to school with a nasogastric (NG) feeding tube in place if they're finding eating and drinking difficult.
Other changes in physical appearance
Some drugs used in cancer treatment can cause the hands, face, feet and ankles to swell. This should reverse once treatment is finished. In some cases, a child or young person may return to school having had a limb amputated or with scars from surgery.
Reduced resistance to infection
Treatment can temporarily reduce a child or young person's immunity, making them more susceptible to infections. At times they may need to avoid crowded places like cinemas, parties or even school. When at school it's particularly important that they avoid contact with pupils who have chickenpox, shingles or measles.
You can download and print a copy of our factsheet for teachers about childhood cancer and its treatment.