Skip to Content
Chronic lymphocytic leukemia (CLL) is cancer of a type of white blood cells called lymphocytes. These cells are found in the bone marrow and other parts of the body. Bone marrow is the soft tissue in the center of bones that helps form all blood cells.
CLL causes a slow increase in a certain type of white blood cells called B lymphocytes, or B cells. Cancer cells spread through the blood and bone marrow. CLL can also affect the lymph nodes or other organs such as the liver and spleen. CLL eventually can cause the bone marrow to lose its function.
CLL; Leukemia - chronic lymphocytic (CLL)
The cause of CLL is unknown. There is no link to radiation. It is unclear if certain chemicals can cause CLL. Exposure to Agent Orange during the Vietnam War has been linked to a slight increased risk of developing CLL.
CLL usually affects older adults, especially those over age 60. People under age 45 rarely develop CLL. CLL is more common in whites than in other ethnic groups. It is more common in men than in women. Some people with CLL have family members with the disease.
Symptoms usually develop slowly. CLL is often found by blood tests done in people for other reasons or who do not have any symptoms.
Symptoms of CLL may include:
People with CLL usually have a high white blood cell count.
Tests to diagnose CLL include:
If your doctor discovers you have CLL, tests will be done to see how much the cancer has spread. This is called staging.
Tests that look at changes in the DNA inside the cancer cells may also be done. Results from these tests and from staging tests help your doctor determine your treatment.
If you have early stage CLL, your doctor will just monitor you closely. Treatment is not generally given for early-stage CLL, unless you have:
Chemotherapy medicines are used to treat CLL. Your doctor will determine which ones are right for you.
In rare cases, radiation is used for painful and enlarged lymph nodes.
Blood transfusions or platelet transfusions may be required if blood counts are low.
Bone marrow or stem cell transplantation may be used in younger people with advanced or high-risk CLL. A transplant is the only therapy that offers a potential cure for CLL, but it also has risks. Your doctor will discuss the risks and benefits with you.
You can ease the stress of illness by joining a cancer support group. Sharing with others who have common experiences and problems can help you not feel alone.
How well a person does depends on the stage of the cancer. About one-half of people diagnosed in the early stages of CLL live more than 12 years.
Complications may include:
Call a health care provider if you develop enlarged lymph nodes or unexplained fatigue, bruising, excessive sweating, or weight loss.
Byrd JC, Flynn JM. Chronic lymphocytic leukemia. In: Niederhuber JE, Armitage JO, Doroshow JH, Kastan MB, Tepper JE, eds. Abeloff's Clinical Oncology. 5th ed. Philadelphia, PA: Elsevier Churchill Livingstone; 2014:chap 102.
National Cancer Institute: PDQ Chronic Lymphocytic Leukemia Treatment. Bethesda, Md: National Cancer Institute. Date last modified: January 16, 2015. Available at: www.cancer.gov/cancertopics/pdq/treatment/CLL/healthprofessional. Accessed: May 12, 2015.
National Comprehensive Cancer Network. NCCN Clinical Practice Guidelines in Oncology: Non-Hodgkin's Lymphomas. Version 1.2015. Available at: www.nccn.org/professionals/physician_gls/pdf/nhl.pdf. Accessed: May 12, 2015
Reviewed By: Rita Nanda, MD, Assistant Professor of Medicine, Section of Hematology/Oncology, University of Chicago Medicine, Chicago, IL. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.