Leukemia in children and teenagers
A leukemia diagnosis in a child shakes the whole family. But this is an area where medicine has achieved one of its greatest successes: today, in well-resourced health systems, most children with leukemia reach long-lasting remission. This topic explains what is special about leukemia in children and teenagers, the treatment journey, and what families can prepare for.
01Short answer
02Simple explanation
The signs of leukemia in children often look like ordinary childhood illnesses: tiredness, paleness, a fever that lingers, frequent infections, easy bruising and nosebleeds. Bone and joint pain is especially typical in children — a child may limp, refuse to walk or want to be carried.
Most childhood leukemias are ALL, and with modern treatment the great majority of these children reach long-lasting remission. AML is less common in children and needs more intensive treatment, but it often responds well to treatment too.
The cause of leukemia in children is usually unknown and is not linked to anything the parents did or did not do. This is very important: no one is to blame. Some inherited conditions (such as Down syndrome) raise the risk, but in most children no such cause is found.
Treatment usually takes place in a specialised pediatric hematology centre with a large team: doctors, nurses, psychologists, social workers and teachers. ALL treatment lasts about 2–3 years, but much of it happens at home on tablets, and children can often go back to school.
Teenagers are a special group: their disease is sometimes harder to treat, and during treatment issues such as school, friendships, body image and independence come to the fore. Treating teenagers with pediatric-style protocols has improved results considerably.
03Scientific explanation
According to the NCI, ALL accounts for about 25% of childhood cancers and is most common at ages 1–4; the ACS notes that ALL peaks at ages 2–5, while childhood AML is more common in the first year of life and in the teenage years. In the US, 52.1% of ALL cases occur in people under 20 (SEER). Chronic leukemias are rare in children; JMML is most common around age 2 (NCI). Down syndrome, Fanconi anemia, Li–Fraumeni syndrome, neurofibromatosis type 1 and other inherited conditions are among the factors that raise risk (NCI).
In childhood ALL, the risk group (NCI PDQ) is based on B or T lineage, age and white count (for example, standard risk: age 1 to under 10 and white count <50,000/µL), genetic findings, CNS or testicular involvement and early treatment response (MRD). Favourable genetic findings include high hyperdiploidy (51–65 chromosomes) and ETV6::RUNX1; unfavourable ones include BCR::ABL1, KMT2A::AFF1 and hypodiploidy (<44 chromosomes). About 98% of children with ALL reach remission (NCI). In infants under 1 year, ALL often carries a KMT2A rearrangement and is harder to treat.
Childhood AML is usually treated with courses of intensive chemotherapy; for high-risk disease, an allogeneic stem cell transplant is considered in first remission. In children with Down syndrome, AML often responds well to chemotherapy, but doses are adjusted because of a higher risk of toxicity; these children may also have transient abnormal myelopoiesis (TAM) as newborns. APL in children is also treated with ATRA and arsenic trioxide.
According to the NCI, survival for teenagers with ALL has risen over recent decades from about 28% to more than 75%; in adolescents and young adults (AYA), pediatric-style protocols have shown better results. Overall 5-year relative survival for childhood leukemia in the US is 86.7% (SEER). However, according to the WHO, more than 80% of children with cancer survive in high-income countries, compared with less than 30% in many low- and middle-income countries; the WHO Global Initiative for Childhood Cancer aims for at least 60% survival for all children by 2030. Survivors are advised to have long-term follow-up of the heart, endocrine system, fertility, cognitive function and the risk of second cancers.
04What happens in the body?
A growing body, a different disease
In children, red marrow is active in almost all bones, so when leukemia cells “push” on the bones from inside, it causes pain. Childhood leukemias are biologically different from adult ones: different genetic changes are more common, and many of them respond well to treatment.
The treatment journey: protocols and team
Children are usually treated on established international protocols or within clinical trials. This means every step is planned in advance and the results are continually studied. Writing down questions and talking openly with the team helps parents a great deal.
Family, school and everyday life
Leukemia affects the whole family — brothers and sisters too. It is important to talk with children honestly and at their level, keep familiar routines where possible and make use of psychological support. Many centres have a hospital school or back-to-school programmes.
After treatment: long-term follow-up
Regular follow-up continues for years after treatment ends. The aim is both to catch any relapse early and to spot and manage late effects of treatment in good time — for example those involving the heart, hormones, growth, learning and fertility.
05The path through childhood leukemia
Four steps — from symptoms to life after treatment.
06Types of leukemia in children at a glance
| Type | How common? | Most common age | Outcome (overall) |
|---|---|---|---|
| ALL | About 3/4 of childhood leukemias | Ages 2–5 | 5-year survival about 90% |
| AML | Most of the rest | First year of life and teenage years | 5-year survival about 65–70% |
| APL (a type of AML) | Rare | Can occur in children | Very good with ATRA + arsenic trioxide |
| JMML | Rare | Around age 2 | Usually needs a transplant |
| CML | Rare | More often teenagers | Good control with TKIs |
* Survival figures are averages from ACS and SEER data and reflect results in high-income countries. Your child’s outlook depends on the features of their disease — the pediatric hematologist will explain this.
07Key terms
- Pediatric hematologist
- A doctor who treats blood diseases in children.
- Protocol
- A treatment plan set out step by step in advance.
- Risk group
- A category that determines how intensive treatment is.
- MRD
- Measurable residual disease — the depth of response to treatment.
- Hyperdiploidy
- Extra chromosomes in the cell; a favourable finding in childhood ALL.
- Down syndrome
- A condition linked to an extra chromosome 21; it raises leukemia risk.
- AYA
- Adolescents and young adults (roughly ages 15–39).
- Late effects
- Health problems that appear months or years after treatment.
- Hospital school
- A programme that lets a child keep learning during treatment.
- Clinical trial
- A study of a new or improved treatment.
08Key points
- Leukemia is the most common cancer in children.
- About 3/4 of childhood leukemias are ALL.
- Bone pain and limping are common signs in children.
- Parents are not to blame — the cause is usually unknown.
- About 90% of children with ALL live at least 5 years.
- Treatment takes place in a specialised pediatric centre with a large team.
- Teenagers benefit from pediatric-style protocols.
- Long-term follow-up after treatment is important.
09Frequently asked questions
Did I cause my child’s leukemia?
No. In most cases of childhood leukemia the cause is unknown and is not linked to parents’ diet, lifestyle or other choices. This feeling is natural, but sharing your guilt with your team or a psychologist can help.
How much should I tell my child, and how?
Talking simply, honestly and at your child’s level is recommended. For young children, an explanation such as “there are sick cells in your blood and the doctors are treating them with medicine” may be enough. Child psychologists and nurses can help you prepare for these conversations.
How can I support brothers and sisters?
They may also feel anxious, jealous or guilty. It helps to explain what is happening, spend time with them on their own and involve them where possible. Some centres have support programmes for siblings.
Can my child go to school during treatment?
Often not during intensive phases, but many children return to school during maintenance. The decision depends on infection risk and your child’s condition. The team can advise on working with the school and on vaccinations.
Is childhood leukemia inherited? Will my other children get it?
In most cases, no. Siblings may have a slightly higher risk, but the absolute risk is still low. If an inherited syndrome is suspected in the family, your doctor may offer genetic counselling.
What follow-up will be needed after treatment?
In the first years after treatment, regular blood tests and check-ups are done, followed by long-term follow-up focused on late effects. International guidelines (such as those of the Children’s Oncology Group) set out which checks are needed and when.
10Questions for your doctor
Take these questions to your appointment. The ones you save are collected on the “My questions” page and stay on this device only.
Which risk group is my child's leukemia in?
How can school and learning continue during treatment?
How do you suggest we talk with our child about the illness?
How will long-term follow-up and late effects be monitored?
12Sources
- American Cancer Society. Childhood Leukemia
- American Cancer Society. Prognostic Factors and Survival Rates for Childhood Leukemia
- American Cancer Society. Signs and Symptoms of Childhood Leukemia
- National Cancer Institute (NCI). Childhood Acute Lymphoblastic Leukemia Treatment (PDQ®) — Patient Version
- National Cancer Institute (NCI). Childhood Acute Lymphoblastic Leukemia Treatment (PDQ®) — Health Professional Version
- National Cancer Institute (NCI). Childhood Acute Myeloid Leukemia and Other Myeloid Malignancies Treatment (PDQ®) — Patient Version
- National Cancer Institute (NCI), SEER. Cancer Stat Facts: Childhood Leukemia (Ages 0–19)
- World Health Organization. Childhood cancer — Fact sheet
- National Cancer Institute (NCI). Late Effects of Treatment for Childhood Cancer (PDQ®) — Patient Version
- National Cancer Institute (NCI). Adolescents and Young Adults with Cancer
- Children’s Oncology Group. Long-Term Follow-Up Guidelines for Survivors of Childhood, Adolescent and Young Adult Cancers
- National Cancer Institute (NCI). Cancer in Children and Adolescents — Fact Sheet