Childhood cancer is a devastating disease and is a leading cause of illness related death in the UK. Whilst adults also get cancer, it is not the same as childhood cancer. The word ‘cancer’ isn’t that specific - it is used to describe over 200 different diseases.
These diseases have a lot of differences between them. Some form solid tumours, some live in the blood, some grow slowly and some are more aggressive and fast growing. There is a mix of diseases that children can get, and they can behave differently to adult cancers.
Despite cancer being a big issue for children and young people, the public has much lower awareness of childhood cancer, its causes, and its symptoms. Not only do children get different types of cancer, but there are also big differences in the treatment, diagnosis, and the cause of their cancer.
So, what are the 6 ways childhood cancer is different to adult cancer?
1. The types of cancer are different
The top cancers that children get are different to the types most often seen in adults. The most common type of cancer in children is leukaemia, a type of blood cancer, and around three in ten children diagnosed with cancer will have some form of leukaemia. A quarter of children will have tumours in their brain or spinal cord while the remaining children diagnosed have other types of childhood cancer such as lymphoma, kidney and bone – there are 76 types in all. For adults, the top three most common cancers are breast, prostate, and lung cancer.
The most common cancers for children are leukaemia, brain and spinal tumours, and lymphoma. The most common cancers for adults are breast, prostate, bowel, and lung cancer.
Some types of childhood cancer can also occur in adults - leukaemia is one example of this. However, adult leukaemia is normally different to the type of leukaemia a baby or child would get. For example, children are more likely to get acute lymphoblastic leukaemia than acute myeloid leukaemia, which is more common in adults.
The difference between the names might seem small, but it is very important. The difference is in where the cancer comes from, meaning which type of blood cell first became cancerous. As these different cells naturally have different properties, they need to be treated differently.
However, there’s not just differences between the overall types of cancer children get – even within a specific cancer type, children’s cancer cells can have completely different genetic mutations to adult cancers. For example, ependymoma tumours are most often seen growing in the spinal cord in adults, but only 10% of children with ependymoma have a spinal tumour as they most often appear in the brain.
2. Treatment has additional considerations
Now that more and more children are surviving cancer, there is a huge focus on finding better and safer treatments. The trouble is that, whilst cancer treatments are designed to kill cancer cells, they are often harmful to healthy cells too. This is a particular problem for children, because their bodies are still developing, and their organs have not fully matured which can impact a doctors treatment choice.
Some treatments, like radiotherapy, are used much less intensively in children than in adults because of this. Surgery can also put more of a focus on preserving healthy tissue in children, to make sure the child’s growth and development won’t be severely affected.
Therefore, the goal of childhood cancer treatment is much bigger than just immediate survival. As children have their future adult lives ahead of them, doctors have to also consider the potential long-term effects of treatment on a child's development.
Despite these difficulties, children with cancer have a much higher chance of survival compared to adults – over eight in ten children survive their cancer for ten years or more, but only five in ten adults do. This is a fantastic improvement compared with only around one child out of ten surviving in the 1950s.
Over eight in ten children now survive their cancer, but only around half of the adults diagnosed with cancer survive.
An explosion in the number of clinical trials, the introduction of specialist childhood cancer treatment centres, and the refinement of treatments have been key to this progress. It’s important to remember that some childhood cancers still have very low survival rates, which means that there is still a lot of work to do.
3. The cause is different
Most adult cancers are caused by natural aging, environmental and lifestyle factors. For example, smoking too much and being exposed to UV rays from the sun can damage your cells’ DNA, causing cancer mutations.
Childhood cancers are also caused by genetic mutations, however, they are rarely due to environmental factors like too much alcohol or cigarettes. There are a few different ways that cells get genetic mutations in childhood cancer, which you can read about in our ‘What are genetic errors in childhood cancer and where did they come from?’ blog. For a lot of childhood cancers, we don’t know exactly why a cell became cancerous, but researchers are working hard to figure it out.
4. Childhood cancer is less common
Adult cancers are more common than childhood cancer. In 2020, there were over 280,000 adults diagnosed with cancer, whereas researchers believe that around 2000 children are diagnosed each year in the UK. Whilst this is lower, the risk is not to be ignored.
To put it another way, for every group of 320 children and young people, one child will be diagnosed with cancer before their 20th birthday. There are on average 280 pupils in a primary school - you can imagine, or may have experienced, the impact that one child's diagnosis can have on a school and its community. Childhood cancer is a huge challenge, one we need to face head on.
Every day, five families will hear the devastating news that their child has cancer. Sadly, one of these families will not see their child cured. That has a huge effect on the family and their community – they will never know who their child would have grown up to be.
5. Better survival means more focus on quality of life
Cancer has a huge effect on childhood cancer survivor lives too. Over 80% of children survive cancer, compared to just 50% of adults. This makes quality of life after treatment very important - one of the top research priorities for childhood cancer is finding a way to prevent the long-term effects of cancer and its treatment.
Around two in three survivors will have one of these long-term effects, known as ‘late effects’. These can have a big impact both physically and emotionally, for example, impact on mental health, fertility, heart disease and growth.
Our Living Beyond Cancer factsheets were developed to help survivors struggling with late effects.
Late effects are still an issue for adult cancer survivors. However, their bodies are fully developed, so their bodies are less sensitive to damage. Children with cancer are still growing and have a whole lifetime in front of them so the effects of treatment have a bigger impact. They have yet to go through key stages in their lives such as finishing education, getting their first job, having children, and much more. Late effects can make this difficult.
6. People don't know the symptoms
Childhood cancer is a leading cause of death in the UK – but over two thirds of the general public say they do not feel confident in identifying its signs and symptoms. Although adult cancer symptoms such as unexplained lumps or weight loss still apply to children, many symptoms can be vague or look like other common childhood illnesses. For example, lots of repeated infections such as chest, throat and ears can be a cause for concern as well as developmental issues such as slow growth, and early or late puberty.
This lack of awareness can cause delays in diagnosis, which can make a big difference to a child’s chance of survival. The number of children surviving cancer in the UK is lower than other countries in Europe and there is evidence that, in one type of cancer, children are diagnosed later. This is why researchers are working hard to understand more about how childhood cancer is diagnosed in the UK, and how we can speed up the process. You can find out more about how awareness matters in our webinar about diagnosing childhood cancer.
Overall, the main thing to remember is that childhood cancers are different to adult cancers. The reality is that childhood cancers behave very differently to adult cancers, are susceptible to different treatments, and even look different down the microscope.
It’s important that people understand the differences, so they can learn the signs and symptoms of cancer in children. Greater awareness can mean faster diagnosis – and faster diagnosis can save lives.
Ellie Ellicott is CCLG’s Research Communication Executive.
She is using her lifelong fascination with science to share the world of childhood cancer research with CCLG’s fantastic supporters. You can find Ellie on X: @EllieW_CCLG
