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 not clear whether certain chemicals cause CLL. But exposure to Agent Orange during the Vietnam War has been linked to an increased risk of getting CLL.

CLL usually affects older adults, especially those older than age 60. Persons under age 45 rarely get it. CLL is more common in whites than in other ethnic groups. It is more common in men than in women. Some persons 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 include:

• Abnormal bruising (if platelets are low)
• Enlarged lymph nodes, liver, or spleen
• Excessive sweating, night sweats
• Fatigue
• Fever
• Infections that keep coming back (recur)
• Loss of appetite or becoming full too quickly (early satiety)
• Weight loss

Patients with CLL usually have a high white blood cell count.

Tests to diagnose CLL include:

• Complete blood count (CBC) with white blood cell differential
• Bone marrow biopsy
• CT scan of the chest, abdomen, and pelvis
• Immunoglobulin testing
• Flow cytometry test of the white blood cells

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 DNA inside the cancer cells may also be done. Results from these tests can from staging tests help your doctor determine your treatment.

If you have early stage CLL, your doctor will monitor you closely. Usually, no medicines or other treatment is given for early-stage CLL, unless you have:

• A high-risk type of CLL
• Infections that keep coming back
• Leukemia that is rapidly getting worse
• Low red blood cells or platelet counts
• Fatigue, loss of appetite, weight loss, or night sweats
• Painful swollen lymph nodes

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 patients with advanced or high-risk CLL. A transplant is the only therapy that offers a potential cure for CLL.

How well a patient does depends on the stage of the cancer. About half of patients diagnosed in the early stages of CLL live more than 12 years.

• Autoimmune hemolytic anemia
• Bleeding from low platelet count
• Hypogammaglobulinemia, a condition in which you have lower levels of antibodies, which increases your risk of infection
• Idiopathic thrombocytopenic purpura (ITP)
• Infections that keep coming back (recur)
• Overwhelming fatigue
• Other cancers, including a much more aggressive lymphoma (Richter’s transformation)
• Side effects of chemotherapy

Call health care provider if you develop enlarged lymph nodes or unexplained fatigue, bruising, excessive sweating, or weight loss.

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Lin TS, Awan FT, Byrd JC. Chronic lymphocytic leukemia. In: Hoffman R, Benz EJ Jr, Silberstein LE, et al., eds. Hematology: Basic Principles and Practice. 6th ed. Philadelphia, PA: Elsevier Saunders; 2012:chap 76.

National Comprehensive Cancer Network. NCCN Clinical Practice Guidelines in Oncology: Non-Hodgkin’s Lymphomas. Version 1.2013. Available at http://www.nccn.org/professionals/physician_gls/pdf/nhl.pdf. Accessed January 2, 2013.