Chronic Lymphocytic Leukemia

by National Cancer Institute

Chronic lymphocytic leukemia is a type of cancer in which the bone marrow makes too many lymphocytes (a type of white blood cell).

Chronic lymphocytic leukemia (also called CLL) is a blood and bone marrow disease that usually gets worse slowly. CLL is the second most common type of leukemia in adults. It often occurs during or after middle age; it rarely occurs in children.

Normally, the body produces bone marrow stem cells (immature cells) that develop into mature blood cells. There are 3 types of mature blood cells:

• Red blood cells that carry oxygen and other materials to all tissues of the body.
• White blood cells that fight infection and disease.
• Platelets that help prevent bleeding by causing blood clots to form.

In CLL, too many stem cells develop into a type of white blood cell called lymphocytes. There are 3 types of lymphocytes:

• B lymphocytes that make antibodies to help fight infection.
• T lymphocytes that help B lymphocytes make antibodies to fight infection.
• Natural killer cells that attack cancer cells and viruses.

The lymphocytes in CLL are not able to fight infection very well. Also, as the amount of lymphocytes increases in the blood and bone marrow, there is less room for healthy white blood cells, red blood cells, and platelets. This may result in infection, anemia, and easy bleeding.

Older age can affect the risk of developing chronic lymphocytic leukemia.

Risk factors for CLL include the following:

• Being middle-aged or older, male, or white.
• A family history of CLL or cancer of the lymph system.
• Having relatives who are Russian Jews or Eastern European Jews.

Possible signs of chronic lymphocytic leukemia include swollen lymph nodes and tiredness.

Usually CLL does not cause any symptoms and is found during a routine blood test. Sometimes symptoms occur that may be caused by CLL or by other conditions. A doctor should be consulted if any of the following problems occur:

• Painless swelling of the lymph nodes in the neck, underarm, stomach, or groin.
• Feeling very tired.
• Pain or fullness below the ribs.
• Fever and infection.
• Weight loss for no known reason.

Tests that examine the blood, bone marrow, and lymph nodes are used to detect (find) and diagnose chronic lymphocytic leukemia.

The following tests and procedures may be used:

Physical exam and history: An exam of the body to check general signs of health, including checking for signs of disease, such as lumps or anything else that seems unusual. A history of the patient's health habits and past illnesses and treatments will also be taken.

Complete blood count (CBC): A procedure in which a sample of blood is drawn and checked for the following:

• The number of red blood cells, white blood cells, and platelets.
• The amount of hemoglobin (the protein that carries oxygen) in the red blood cells.
• The portion of the blood sample made up of red blood cells.

Cytogenetic analysis: A test in which cells in a sample of blood or bone marrow are viewed under a microscope to look for changes in the structure or number of chromosomes in the lymphocytes.

Immunophenotyping: A test in which the cells in a sample of blood or bone marrow are looked at under a microscope to find out if malignant lymphocytes (cancer) began from the B lymphocytes or the T lymphocytes.

Bone marrow aspiration and biopsy: The removal of a small piece of bone and bone marrow by inserting a needle into the hipbone or breastbone. A pathologist views both the bone and bone marrow samples under a microscope to look for abnormal cells.

Certain factors affect treatment options and prognosis (chance of recovery).

Treatment options depend on:

• The stage of the disease.
• Red blood cell, white blood cell, and platelet blood counts.
• Whether there are symptoms, such as fever, chills, or weight loss.
• Whether the liver, spleen, or lymph nodes are larger than normal.
• The response to initial treatment.
• Whether the CLL has recurred (come back).

The prognosis (chance of recovery) depends on:

• Whether there is a change in the DNA and the type of change, if there is one.
• Whether lymphocytes are spread throughout the bone marrow.
• The stage of the disease.
• Whether the CLL gets better with treatment or has recurred (come back).
• Whether the CLL progresses to lymphoma or prolymphocytic leukemia.
• The patient's general health.

Stages of Chronic Lymphocytic Leukemia

After chronic lymphocytic leukemia has been diagnosed, tests are done to find out how far the cancer has spread in the blood and bone marrow.

Staging is the process used to find out how far the cancer has spread. It is important to know the stage of the disease in order to plan the best treatment. The following tests may be used in the staging process:

Bone marrow aspiration and biopsy: The removal of a small piece of bone and bone marrow by inserting a needle into the hipbone or breastbone. A pathologist views both the bone and bone marrow samples under a microscope to look for abnormal cells.

Chest x-ray: An x-ray of the organs and bones inside the chest. An x-ray is a type of energy beam that can go through the body and onto film, making a picture of areas inside the body, such as the lymph nodes.

MRI (magnetic resonance imaging): A procedure that uses a magnet, radio waves, and a computer to make a series of detailed pictures of areas inside the body, such as the brain and spinal cord. This procedure is also called nuclear magnetic resonance imaging (NMRI).

CT scan (CAT scan): A procedure that makes a series of detailed pictures of areas inside the body, taken from different angles. The pictures are made by a computer linked to an x-ray machine. A dye may be injected into a vein or swallowed to help the organs or tissues show up more clearly. This procedure is also called computed tomography, computerized tomography, or computerized axial tomography.

Blood chemistry studies: A procedure in which a blood sample is checked to measure the amounts of certain substances released into the blood by organs and tissues in the body. An unusual (higher or lower than normal) amount of a substance can be a sign of disease in the organ or tissue that produces it.

Antiglobulin test: A test in which a sample of blood is looked at under a microscope to find out if there are any antibodies on the surface of red blood cells or platelets. These antibodies may react with and destroy the red blood cells and platelets. This test is also called a Coomb's test.

The following stages are used for chronic lymphocytic leukemia:

Stage 0

In stage 0 chronic lymphocytic leukemia, there are too many lymphocytes in the blood, but there are no other symptoms of leukemia. Stage 0 chronic lymphocytic leukemia is indolent (slow-growing).

Stage I

In stage I chronic lymphocytic leukemia, there are too many lymphocytes in the blood and the lymph nodes are larger than normal.

Stage II

In stage II chronic lymphocytic leukemia, there are too many lymphocytes in the blood, the liver or spleen is larger than normal, and the lymph nodes may be larger than normal.

Stage III

In stage III chronic lymphocytic leukemia, there are too many lymphocytes in the blood and there are too few red blood cells. The lymph nodes, liver, or spleen may be larger than normal.

Stage IV

In stage IV chronic lymphocytic leukemia, there are too many lymphocytes in the blood and too few platelets. The lymph nodes, liver, or spleen may be larger than normal and there may be too few red blood cells.

Refractory Chronic Lymphocytic Leukemia

Refractory chronic lymphocytic leukemia is cancer that does not get better with treatment.

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