Chronic lymphocytic leukemia is cancer of the white blood cells (lymphocytes).

See also:

• Acute lymphocytic leukemia (ALL)
• Chronic myelogenous leukemia (CML)
• Leukemia

Chronic lymphocytic leukemia (CLL) causes a slow increase in the number of white blood cells called B cells in the bone marrow. The cancerous cells spread from the blood marrow to the blood, and can also affect the lymph nodes and other organs. CLL eventually causes the bone marrow to fail and weakens the immune system.

The reason for this increase in B cells is unknown. There is no link to radiation, cancer-causing chemicals, or viruses.

CLL primarily effects adults. The average age of patients with this type of leukemia is 70. It is rarely seen in people younger than 40. The disease is more common in Jewish people of Russian or East European descent, and is uncommon in Asians.

Symptoms usually develop gradually. Many cases of CLL are detected by routine blood tests in people who do not have any symptoms.

Symptoms that can occur include:

• Abnormal bruising (occurs late in the disease)
• 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)
• Unintentional weight loss

Patients with CLL usually have a higher-than-normal white blood cell count.

Tests to diagnose and assess CLL include:

• Complete blood count (CBC) with white blood cell differential
• Bone marrow aspiration and biopsy
• CT scan of the chest, abdomen, and pelvis
• Flow cytometry
• Serum immunoglobin level
• Serum lactate dehydrogenase (LDH) level

If your doctor discovers you have CLL, tests will be done to see how much the cancer has spread. This is called staging.

There are two systems used to stage CLL:

The Rai system uses numbers to group CLL into low-, intermediate-, and high-risk categories. Generally, the higher the stage number, the more advanced the cancer.

The Binet system uses letters to stage CLL according to how many lymph node groups are involved and whether you have a drop in the number of red blood cells or platelets.

Early stage disease often requires no specific treatment, but it is important to be closely monitored by your doctor.

Chemotherapy may be needed if fatigue, anemia, thrombocytopenia, recurrent infections, or lymph node swelling occurs. Several chemotherapy drugs are commonly used to treat CLL. Fludarabine, chlorambucil, cyclophosphamide (Cytoxan), and rituximab (Rituxan) may be used.

Alemtuzumab (Campath) is approved for treatment of patients with CLL that has not responded to fludarabine. Bendamustine is a newer drug recently approved for use in patients with CLL that has come back after initial treatment.

Rarely, radiation may be used for enlarged lymph nodes. Blood transfusions or platelet transfusions may be required. Bone marrow or stem cell transplantation may be used in younger patients with advanced CLL. Right now, transplant is the only therapy that offers a potential cure for CLL.

The outlook depends on the stage and behavior of the disease. Half of patients diagnosed in the earliest stages of the disease live more than 12 years. Some people may not require any treatment at all, while others may have faster spreading disease that requires therapy.

Newer tests that look at cell and genetic changes may be done.

• Autoimmune hemolytic anemia
• Bleeding from low platelets
• Fatigue from anemia
• Hypogammaglobulinemia (reduced levels of antibodies) -- increases the risk of infection
• Idiopathic thrombocytopenic purpura (ITP)
• Other cancers
• Side effects of chemotherapy

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

National Comprehensive Cancer Network. NCCN Guidelines in Oncology 2009: Non-Hodgkin's Lymphomas. Version 1.2009.

Kantarjian H, O'Brien S. The chronic leukemias. In: Goldman L, Ausiello D, eds. Cecil Textbook of Medicine. 23rd ed. Philadelphia, Pa: Saunders Elsevier; 2007: chap 195.