what is leukemia | What is chronic lymphoid leukemia?

What is chronic lymphoid leukemia?

Chronic lymphoid leukemia (LLC) is the most common leukemia in Western countries. It touches men preferentially (1). The average age for diagnosis is 70 years (1). The LLC is neither contagious nor hereditary, although there are some family forms. (2) Leukemia is a type of bone marrow and blood cancer, responsible for an increase in the number of a particular type of white blood cells. (1) Leukemias are classified according to the type of white blood cells reached. In the LLC, the increased number of white blood cells are lymphocytes. Lymphocytes normally help our bodies fight infections. The lymphocytes involved are type B.

Our lymphatic system is a system made up of lymphatic vessels that travel all over the body. (3) They carry lymph, a clear liquid containing a high number of lymphocytes.

Along the lymphatic vessels are small lymph glands in the form of beans or lymph nodes. The normal lymphocytes present in the lymph nodes come into contact with different infectious agents and activate the immune system to eliminate them. (1.3)

In the case of an LLC, lymphocytes are cells that do not function normally and multiply in an uncontrolled manner. They accumulate at the level of the lymph nodes, bone marrow, blood circulation and other organs such as the spleen, which can eventually lead to the increase in volume of one or more of these organs. (1.2) B cells multiplying so uncontrollably are called "Malignant B cells".

Malignant B cells escape the organism's systems that control the life span and cell proliferation. Normally, B cells have a short lifespan. Over time, malignant B cells accumulate and prevent the normal production of other blood cells. 1

The LLC is considered a relatively slow-changing cancer. But it can become aggressive (or progress) and is more difficult to deal with. This evolution can occur quickly or slowly, and differently from one individual to another. 1

(1) HAS. Patient Guide Chronic lymphoid leukemia. September 2011.

(2) French Society of Hematology. Patient Information Sheet on chronic lymphoid leukemia. March 2009.

(3) OUP. Concise colour Medical Dictionary. Fifth Edition. Oxford University Press, 2010.