General Information About Chronic Lymphocytic Leukemia
Key Points
Chronic lymphocytic leukemia is a type of cancer in which the bone marrow makes too many lymphocytes (a type of white blood cell).
Leukemia may affect red blood cells, white blood cells, and platelets.
Older age can affect the risk
of developing chronic lymphocytic leukemia.
Signs and symptoms of chronic lymphocytic leukemia include swollen lymph nodes and tiredness.
Tests that examine the blood, bone marrow, and lymph nodes are used to detect
(find) and diagnose chronic lymphocytic leukemia.
Certain factors affect treatment options and prognosis (chance
of recovery).
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 one of the most common types of leukemia
in adults. It often occurs during or after middle age; it rarely occurs in children.
Anatomy of the bone. The bone is made up of compact bone, spongy bone, and bone marrow. Compact bone makes up the outer layer of the bone. Spongy bone is found mostly at the ends of bones and contains red marrow. Bone marrow is found in the center of most bones and has many blood vessels. There are two types of bone marrow: red and yellow. Red marrow contains blood stem cells that can become red blood cells, white blood cells, or platelets. Yellow marrow is made mostly of fat.
Leukemia may affect red blood cells, white blood cells, and platelets.
Blood cell development. A blood stem cell goes through several steps to become a red blood cell, platelet, or white blood cell.
In CLL, too many blood stem cells become abnormal
lymphocytes and do not become healthy white blood cells. The abnormal lymphocytes may also be called leukemia cells. The lymphocytes are not able to fight infection very well. Also, as the number 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 cause infection, anemia, and easy bleeding.
This summary is about chronic lymphocytic leukemia.
See the following PDQ
summaries for more information about leukemia:
Older age can affect the risk
of developing chronic lymphocytic leukemia.
Anything that increases your risk of getting a disease is called a risk factor. Having a risk factor does not mean that you will get cancer; not having risk factors doesn’t mean that you will not get cancer. Talk with your doctor if you think you may be at risk. Risk factors for CLL include the following:
Having relatives who are Russian Jews or Eastern European Jews.
Signs and symptoms of chronic lymphocytic leukemia include swollen lymph nodes and tiredness.
Usually CLL does not cause any signs
or symptoms
and is found during a routine blood test. Signs and symptoms may be caused by CLL or by other conditions. Check with your doctor if you have any of the following:
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.
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.
Complete blood count (CBC). Blood is collected by inserting a needle into a vein and allowing the blood to flow into a tube. The blood sample is sent to the laboratory and the red blood cells, white blood cells, and platelets are counted. The CBC is used to test for, diagnose, and monitor many different conditions.
Immunophenotyping: A laboratory test
in which the antigens
or markers
on the surface of a blood or bone marrow cell are checked to see if they are lymphocytes or myeloid cells. If the cells are malignant
lymphocytes (cancer), they are checked to see if they are B lymphocytes or T lymphocytes.
FISH
(fluorescence in situ hybridization): A laboratory technique used to look at genes
or chromosomes
in cells and tissues. Pieces of DNA
that contain a fluorescent dye are made in the laboratory and added to cells or tissues on a glass slide. When these pieces of DNA bind to specific genes or areas of chromosomes on the slide, they light up when viewed under a microscope with a special light.
Flow cytometry: A laboratory test
that measures the number of cells in a sample, the percentage of live cells in a sample, and certain characteristics of cells, such as size, shape, and the presence of tumor markers
on the cell surface. The cells are stained with a light-sensitive dye, placed in a fluid, and passed in a stream before a laser
or other type of light. The measurements are based on how the light-sensitive dye reacts to the light.
IgVH gene mutation
test: A laboratory test done on a bone marrow or blood sample to check for an IgVH gene mutation. Patients with an IgVH gene mutation have a better prognosis.
Bone marrow aspiration
and biopsy: The removal of bone marrow, blood, and a small piece of bone by inserting a hollow needle into the hipbone or breastbone. A pathologist
views the bone marrow, blood, and bone under a microscope to look for abnormal cells.Bone marrow aspiration and biopsy. After a small area of skin is numbed, a bone marrow needle is inserted into the patient’s hip bone. Samples of blood, bone, and bone marrow are removed for examination under a microscope.
Certain factors affect treatment options and prognosis (chance
of recovery).
