Leukaemia is a cancer of the blood‑forming cells in the bone marrow (the soft centre inside bones). In leukaemia, the marrow makes too many abnormal white blood cells called “blasts”. These blasts do not work properly and crowd out healthy blood cells. Because the bone marrow cannot make enough healthy blood cells, children may get infections, anaemia (low red blood cells), and bruising or bleeding (low platelets). Most leukaemia in children is acute, meaning it develops quickly and needs urgent treatment. [1]
Childhood leukaemia is usually classified into:
Acute lymphoblastic leukaemia (ALL): the most common type in children.
Acute myeloid leukaemia (AML): less common than ALL, and treated with different medicines than those of ALL.
Chronic leukaemias (such as CML or JMML): rarer; treatment and outlook are different.
Leukaemia is the most common childhood cancer. In Singapore, leukaemia accounts for about 30–40% of childhood cancers.
In most children, we cannot point to a single cause. Leukaemia usually happens because of changes (mutations) that occur in developing blood cells as a child grows. These changes are not caused by anything parents did or did not do, and most cases are not inherited.
Some rare genetic conditions and previous high‑dose chemotherapy or radiotherapy can increase the risk. Your doctor will ask about your family history and past medical history to better understand this.
Signs And Symptoms Of Leukaemia
Many symptoms are caused by low blood counts or by leukaemia cells collecting in organs.
Fever or frequent infections
Unusual tiredness, looking pale, shortness of breath
Easy bruising, tiny red/purple spots on the skin (petechiae), nosebleeds or gum bleeding
Bone or joint pain, limping
Swollen lymph nodes (neck, armpit, groin)
Poor appetite or weight loss
Abdominal swelling from an enlarged liver or spleen
Headache, vomiting, seizures, or vision changes (if the central nervous system is involved—less common)
Diagnosis And Treatment Options For Leukaemia
Doctors combine the child’s symptoms, physical examination and blood tests. If leukaemia is suspected, further tests are needed to confirm the diagnosis and plan treatment. These tests are done by paediatric oncology teams and are usually performed with sedation or anaesthesia when needed.
Blood tests (full blood count and blood film): may show low red cells/platelets and abnormal white cells or blasts.
Bone marrow aspirate/biopsy under sedation or anaesthesia: a small sample is taken (usually from the hip bone) to confirm leukaemia and identify the exact type.
Genetic and molecular tests on leukaemia cells: help with risk grouping and choosing the best treatment.
Lumbar puncture (spinal tap): checks if leukaemia cells are in the fluid around the brain and spinal cord; also allows chemotherapy to be given into this space when needed.
Treatment overview (what families can expect)
Treatment is tailored to the leukaemia type (ALL vs AML), risk group, the child’s age, and how well the leukaemia responds early in therapy. Most children start treatment soon after diagnosis.
Treatment is usually given in phases. For ALL, these commonly include induction, consolidation, delayed intensification, and maintenance; AML treatment uses intensive chemotherapy cycles and may include stem cell transplant in selected cases.
Chemotherapy: the main treatment for most childhood leukaemias. Given by mouth, injection, drip (IV), and sometimes into the spinal fluid (intrathecal).
Targeted therapy: medicines that act on specific changes in leukaemia cells (for example, tyrosine kinase inhibitors like dasatinib or ponatinib for Philadelphia chromosome–positive ALL).
Immunotherapy: treatments that help the immune system recognise and attack leukaemia cells. Examples include blinatumomab (a ‘bispecific’ antibody) and CAR T‑cell therapy for some children with relapsed/refractory B‑cell ALL. [2]
Haematopoietic stem cell transplant (bone marrow transplant): used for selected high‑risk or relapsed cases, depending on response and leukaemia features.
At NUH, care has continued to move toward ‘risk‑adapted’ and ‘response‑guided’ treatment—giving enough therapy to cure the leukaemia while reducing side effects where it is safe to do so.
We perform cutting-edge risk stratification using genetic testing and minimal residual disease (MRD) monitoring (very sensitive tests that detect tiny amounts of leukaemia after treatment). These results help us appropriately intensify or reduce treatment. [5]
Upfront role for the use of immunotherapy such as blinatumomab. Large clinical trials and guideline updates have expanded the role of blinatumomab, including earlier treatment for some children, and our centre has started incorporating it as well. [3,6]
At NUH, we provide CAR T‑cell therapy, a cutting-edge option for children with relapsed/refractory B‑cell ALL and T-cell ALL, with high remission rates. We are the first centre to offer CD7 CAR-T to patients and have published the results in our study in Nature Medicine. [4,7]
Depending on your child’s leukaemia risk, our centre performs stem cell transplants using donors who are a full match (such as a sibling or unrelated donor), as well as haploidentical (half-matched) donors, which are often parents. This means that more children can safely receive a transplant even if a fully matched donor is not available. We also have the capability to perform ex vivo T-cell depletion, a specialised laboratory technique that removes specific immune cells from the donor graft before transplantation. This approach helps reduce complications such as graft-versus-host disease (GVHD) while maintaining the anti-leukaemia effect of the transplant.
Supportive care has improved (infection prevention, safer transfusions, and better nausea control), helping children tolerate treatment and recover.
Side effects depend on the treatment phase and the medicines used. The clinical team will explain what to watch for and how to reduce risks.
Infections: chemotherapy lowers immunity. Families are taught when to come to the hospital urgently (for example, fever).
Low blood counts: may need transfusions of red cells or platelets.
Nausea, appetite changes, mouth ulcers: medicines and diet support help a lot.
Hair loss and tiredness: common and usually temporary.
Long‑term effects: some children may have learning, growth, heart, hormone, bone or fertility issues depending on treatments received. Survivorship clinics help monitor and manage these.
Outcomes (Prognosis)
Outcomes depend on the type of leukaemia, genetic features, and early response to treatment. Many children with ALL can be cured, and survival has improved markedly over the decades.
In Singapore, our data indicate that more than 80% of children with ALL are long‑term survivors, with the most favourable groups having more than 95% long-term survival. This is on par with the most developed nations in high-income settings where 5‑year survival for childhood ALL is now commonly reported around the 80-90% range.
Research and Clinical Trials
Clinical trials are an essential reason outcomes have improved over time. When appropriate, your doctor may discuss trial options that compare standard therapy with newer approaches aimed to improve cure rates or reduce side effects. Participation is always voluntary, and children receive excellent standard care whether they join a trial.
At National University Hospital, we take part in leading clinical research to improve treatment for childhood leukaemia. Current studies include:
