This section is for teenagers and young adults. It is about a type of cancer called acute lymphoblastic leukaemia (ALL). The other main type of leukaemia that can affect teenagers and young adults is acute myeloid leukaemia. If you have a different type of leukaemia and want to know more, please contact us.
Our section on leukaemia in general has information about ALL for people of all ages. It also has information about other types of leukaemia that are more common in older people.
Knowing a bit about how the body makes blood cells can help you understand leukaemia and its treatment. It might help to watch the short animation on the right about how your blood works.
Leukaemia is a cancer that affects the white blood cells in your body. Normally, white blood cells divide and grow in a controlled way. In leukaemia, this process goes out of control. People with ALL make too many immature blood cells. These are called lymphoblasts, or sometimes they are called blasts. As the lymphoblasts do not mature, they cannot fight infection as normal white blood cells do.
These immature cells fill up the bone marrow. This means there is no space to make the healthy white cells, red cells and platelets your body needs. The body needs these cells to:
- help us fight infection (white cells)
- carry oxygen from the lungs around our body (red blood cells)
- help blood to clot to stop us bleeding and bruising (platelets).