Leukaemia is a blood cancer that causes an uncontrolled production of abnormal and immature white cell, impacting normal blood cell production in the bone marrow and reducing the number of healthy mature cells.

There are three types of leukaemia that affect children and young adults, which are named according to the type of white blood cell affected (lymphoid or myeloid) and how the disease appears and progresses (acute or chronic):

• acute lymphoblastic leukaemia (ALL) – affects immature cells known as lymphocytes developing in the bone marrow
• acute myeloid leukaemia (AML) – develops in myeloid cells in the bone marrow
• chronic myeloid leukaemia (CML) – a slow growing leukaemia associated with a chromosomal abnormality that impacts the development of white blood cells

According to the Singapore Childhood Cancer Registry, leukaemia is the most common type of childhood cancer in Singapore comprising 44% of all cancers. ALL is the most common leukaemia, while CML is extremely rare. With recent advancements in cancer treatments, overall survival rates for childhood leukaemia now sit at 86.9%.

As acute leukaemia, including ALL and AML, is a rapidly progressing disease, symptoms may only be experienced for a short period of time (days or weeks) prior to diagnosis. In comparison, CML progresses slowly over months to years and symptoms may only occur at an advanced stage.

Signs and symptoms of leukaemia in children include:

• Anaemia
• Increased bleeding or bruising
• Repeated infections
• Bone pain
• Swollen lymph nodes
• Chest pain
• Abdominal pain due to enlarged liver or spleen