Acute Lymphoblastic Leukemia

[Original article on NHS Choices website]

Leukemia is cancer of the white blood cells. Symptoms of leukemia include:

  • pale skin
  • tiredness
  • breathlessness
  • having repeated infections over a short space of time

Acute leukaemia means that the condition progresses rapidly and aggressively and requires immediate treatment. These pages focus on acute lymphoblastic leukemia (Also see Types of acute leukaemia).

Bone marrow

All of the blood cells in the body are produced by bone marrow. Bone marrow is a spongy material that is found inside the bones. It is important because it produces special cells that are called stem cells. Stem cells are very useful because they have the ability to create other specialized cells that carry out important functions. The stem cells in bone marrow produce three important types of blood cells:

  • red blood cells – which carry oxygen around the body
  • white blood cells – which help fight infection
  • platelets – which help stop bleeding

Usually the bone marrow produces stem cells which are allowed to mature into “adult” blood cells. However, in cases of acute leukemia, the affected bone marrow begins to release a large number of immature white blood cells that are known as blast cells. The immature white blood cells begin to rapidly disrupt the normal balance of cells in the blood. This means that the body does not have enough red blood cells or platelet cells. This can cause symptoms of anemia, such as tiredness, and increase the risk of excessive bleeding. Also, as the white blood cells are not properly formed they become less effective at fighting bacteria and viruses, making you more vulnerable to infection. If you have acute leukemia that is left untreated, you will not be able to survive because your blood supply will not function properly.

Types of acute leukemia

Acute leukaemia is classified according to the type of white blood cells that are affected by cancer. There are two main types of white blood cell:

  • lymphocytes – which are mostly used to fight viral infections
  • myeloid cells – which perform a number of different functions, such as fighting bacterial infections, defending the body against parasites and preventing the spread of tissue damage

There are two main types of acute leukemia that are related to the two main types of white blood cells. They are:

  • acute lymphoblastic leukemia – which is cancer of the lymphocytes
  • acute myeloid leukemia – which is cancer of the myeloid cells

These pages focus on acute lymphoblastic leukaemia (ALL). For information on acute myeloid leukemia, go to the Health A-Z topic on acute myeloid leukemia

How common is acute lymphoblastic leukemia?

Acute leukaemia is an uncommon type of cancer. Each year, in England and Wales, an estimated 2,400 new cases are diagnosed. Of these cases of acute leukaemia, about 600 are ALLs. Despite being uncommon overall, ALL is the most common type of cancer to affect children. Approximately 1 in every 2,000 children will develop ALL. About 85% of cases of ALL occur in children who are under the age of 15, with the majority of cases developing in two-to-five-year-olds. The cause or causes of acute leukaemia are uncertain, but known risk factors include:

  • exposure to high levels of radiation
  • exposure to benzene, which is a chemical that is used in manufacturing and is also found in cigarettes


The outlook for children with ALL is usually good. Almost all children will achieve a remission (a period of time where they are free from symptoms) from their symptoms, and 85% will be completely cured. The outlook for adults with ALL is less promising as only 40% of people will be completely cured. Treatments for acute leukaemia usually involve a combination of chemotherapy and radiotherapy. In some cases, a bone marrow transplant may also be used to achieve a cure. If a cure is not possible, there is a risk that the lack of healthy blood cells can make people extremely vulnerable to life-threatening infections (due to the lack of white blood cells) or uncontrolled and serious bleeding (due to the lack of platelets). Each year, in England and Wales, there is an average of 230 deaths from ALL.

Published Date
2010-12-11 15:33:15Z
Last Review Date
2010-05-23 00:00:00Z
Next Review Date
2012-05-23 00:00:00Z