Leukemia is a blood cancer caused by a rise in the number of white blood cells in your body. Those white blood cells crowd out the red blood cells and platelets that your body needs to be healthy. The extra white blood cells don’t work right.
It is an abnormal blood cell produced in the bone marrow.
Leukemia symptoms vary, depending on the type of leukemia. Common leukemia signs and symptoms include:
- Fever or chills
- Persistent fatigue, weakness
- Frequent or severe infections
- Losing weight without trying
- Swollen lymph nodes, enlarged liver or spleen
- Easy bleeding or bruising
- Recurrent nosebleeds
- Tiny red spots in your skin (petechiae)
- Excessive sweating, especially at night
- Bone pain or tenderness
Types of Leukemia
The four most common types of leukemia are:
Acute lymphocytic leukemia (ALL)
This is more common in children.
This type of leukemia begins in the B or T lymphocytes, which are immature white blood cells. Lymphocytes are the building blocks of the lymphoid tissues that make up the immune system.
ALL can affect the bone marrow all over the body.
It can also spread to the:
- Lymph nodes
Doctors further sub-classify ALL based on the variety and developmental stage of the lymphocyte involved.
Acute myeloid leukemia (AML)
This is the most common type of acute leukemia in adults.
It tends to progress quickly. It can affect any component of the blood and there are many subtypes of AML.
Blood stem cells in the bone marrow form into either:
- Lymphoid cells, which become white blood cells.
- Myeloid cells, which can become red blood cells, white blood cells, or platelets.
In AML, myeloid stem cells usually mature into abnormal myeloblasts, or white blood cells. But, they sometimes become abnormal red blood cells or platelets.
As they multiply, they overwhelm the normal cells in the bone marrow and blood. The cancer cells can also spread to other parts of the body.
Chronic lymphocytic leukemia (CLL)
This accounts for about a third of leukemia diagnoses. It usually affects older adults.
One form of CLL progresses slowly. Symptoms may not appear until years after onset. Another form of CLL grows very quickly.
CLL begins in the B lymphocytes. As the abnormal cells proliferate, they crowd out the normal cells.
More subtypes of CLL exist that affect other types of cells.
Chronic myeloid leukemia (CML)
This type of leukemia is rare. Only 10 percent of leukemias are CML.
Adults are more likely than children to get CML.
CML occurs when a genetic change turns the myeloid cells into immature cancer cells. These cells then grow slowly and overwhelm the healthy cells in the bone marrow and blood.
A subtype of CML can form very quickly. This type is hard to treat.
Hairy cell leukemia
A rare type called hairy cell leukemia (HCL) because of how it looks under a microscope affects fewer than 6,000 people each year.
HCL grows slowly. Some people live with the disease for many years before symptoms appear.
Treatments for leukemia include
- chemotherapy (major treatment modality for leukemia)
- Radiation therapy
- Biological therapy
- Targeted therapy
- Stem cell transplant
Combinations of these treatments may be used. Surgical removal of the spleen can be a part of treatment if the spleen is enlarged.