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Macmillan and Cancerbackup merged in 2008. Together we provide free, high quality information for people affected by cancer through our publications, website and phone service. Find out more|.
Find out how we produce our information|
Chronic lymphocytic leukaemia (CLL) is the most common type of leukaemia|. About 2,400 people in the UK are diagnosed with it each year.
CLL usually develops very slowly and many people don’t need treatment for months or years. However, some people need to have treatment straight away.
People with CLL make too many white blood cells called lymphocytes|. When examined under a microscope, the lymphocytes look normal, but they aren’t fully developed (immature) and don’t work properly. Over time these abnormal lymphocytes build up in the lymphatic system and cause large, swollen lymph nodes. They may also fill the bone marrow, reducing the number of normal white cells, red cells and platelets that can be made.
To help you understand CLL and its treatment it’s useful to know a little bit about your blood, what it does and how it’s made|.
For answers, support or just a chat, call the Macmillan Support Line free (Monday to Friday, 9am-8pm)
If you have any questions about cancer, need support or just want someone to talk to, ask Macmillan.