About leukaemia

What is leukaemia?

Leukaemia is a cancer that affects white blood cells. To understand leukaemia it helps to understand a bit about how blood cells are made.

Blood cells

New cells are made in your bone marrow. This is the soft spongy tissue that fills the centre of some of your bones. All blood cells come from a cell known as a stem cell. They start out as immature cells (blast cells) and then they develop into different types of mature blood cells.

Lymphoid stem cells develop into lymphocytes. These white blood cells fight infection. They are further divided into T-cells and B-cells, depending on how they fight infection.
Myeloid stem cells go on to form red blood cells, platelets and other types of white cells.

As blood cells develop, they move out of the bone marrow and into your bloodstream, where they do different jobs

Red blood cells carry oxygen to all the tissues in your body.
White blood cells are involved in fighting infection. Neutrophils are a type of white blood cell that protect you from infection; they are the most common type of white blood cells in your body.
Platelets are involved in blood clotting.

Your body is constantly producing enough cells to keep this process going.

About leukaemia

Blood cancers happen when something goes wrong with the development of blood cells in your bone marrow.

With leukaemia, blast cells are produced but they don’t develop properly. Instead the immature cells build up in your bone marrow and the number of healthy cells is reduced. You get sick because there aren’t enough healthy blood cells to do their jobs in the body.

Types of leukaemia

There are four main types of leukaemia:

Their names come from the type of cell affected by the leukaemia (myeloid blast cells or lymphoid blast cells) and from how quickly they develop (chronic or acute).