Chronic lymphocytic leukaemia (CLL) is the most common adult blood cancer in the Western world, and it predominantly affects older adults. Most people are diagnosed after the age of 70, but increasing numbers of younger people, some under 60, are also being affected.
CLL starts when a type of immune cell called a B cell – normally responsible for producing antibodies – becomes cancerous. This not only stops it from working properly, but also weakens the rest of the immune system.
