Some people have a very high number of white blood cells in their blood when they are diagnosed with leukaemia. The cells can clog up blood vessels and cause problems. Doctors can remove the extra cells from the blood using a machine called a cell separator. This process is called leukapheresis.
This treatment may also be used for women who are pregnant when they are diagnosed.
You lie on a bed or reclining chair with a small plastic tube (cannula) in each arm. Each cannula is connected to the cell separator by a tube. Blood goes from one of your arms through the tube into the cell separator.
As the blood travels through the cell separator, the machine removes the white blood cells. The rest of your blood and blood cells are then returned to your body through the cannula in your other arm. This takes a few hours.
Leukapheresis is painless, but some people may find it uncomfortable having the cannula put in.