Overview of Leukemias

What is leukemia?

Leukemia is cancer of the blood cells — usually the white blood cells. Leukemic cells look different than normal cells and do not function properly.

What are the different types of leukemia?

There are 4 main types of leukemia, which can be further divided into subtypes. When classifying the type of leukemia, the first steps are to determine if the cancer is:

1. Lymphocytic or myelogenous leukemia. Cancer can occur in either the lymphoid or myeloid white blood cells:

   • Lymphocytic leukemia. This is when the cancer develops in the lymphocytes (lymphoid cells).

   • Myelogenous leukemia. This is when the cancer develops in the myeloid cells, usually the granulocytes or monocytes.

2. Acute or chronic leukemia. Leukemia is either acute or chronic:

   • Acute leukemia. The new or immature cancer cells, called blasts, remain very immature and cannot perform their functions. The blasts increase in number rapidly, and the disease progresses quickly.

   • Chronic leukemia. The leukemia cells are more mature and are often able to perform some of their functions. The cells grow more slowly, and the number increases less quickly, so the disease progresses gradually.

Based on these findings, the leukemia is then classified into one of the 4 main types of leukemias:

• Acute myelogenous leukemia (AML)

• Chronic myelogenous leukemia (CML)

• Acute lymphocytic leukemia (ALL)

• Chronic lymphocytic leukemia (CLL)

There are other types and subtypes of leukemias.

What are the symptoms of leukemia?

The following are the most common symptoms of leukemia. However, each individual may experience symptoms differently. Symptoms may include:

• Increased susceptibility to infections and fevers

• Feeling weak or tired

• Pale skin

• Shortness of breath

• Bleeding

• Bruising

• Fever

• Chills

• Loss of appetite

• Loss of weight

• Swollen or tender lymph nodes, liver, or spleen

• Petechiae. Tiny red dots under the skin that are the result of very small bleeds.

• Swollen or bleeding gums

• Sweating

• Bone or joint pain

In addition, acute leukemia may cause the following:

• Headaches

• Vomiting

• Confusion

• Loss of muscle control

• Seizures

• Swollen testicles

• Sores in the eyes or on the skin

Leukemia may also affect the skin, central nervous system, digestive tract, kidneys, and testicles.

The symptoms of acute and chronic leukemias may resemble other blood disorders or medical problems. Always consult your health care provider for a diagnosis.

How is leukemia diagnosed?

In addition to a complete medical history and physical examination, diagnostic procedures for leukemia may include the following:

• Bone marrow aspiration and/or biopsy. A procedure that involves taking a small amount of bone marrow fluid (aspiration) and/or solid bone marrow tissue (called a core biopsy), usually from the hip bones, to be examined for the number, size, and maturity of blood cells and/or abnormal cells.

• Complete blood count (CBC). A measurement of size, number, and maturity of different blood cells in a specific volume of blood.

• Additional blood tests. These may include blood chemistries, evaluation of liver and kidney functions, and genetic studies.

• Computed tomography scan (also called a CT or CAT scan). A diagnostic imaging procedure that uses a combination of X-rays and computer technology to produce horizontal, or axial, images (often called slices) of the body. A CT scan shows detailed images of any part of the body, including the bones, muscles, fat, and organs. CT scans are more detailed than general X-rays.

• Magnetic resonance imaging (MRI). A diagnostic procedure that uses a combination of large magnets, radiofrequencies, and a computer to produce detailed images of organs and structures within the body.

• X-ray. A diagnostic test that uses invisible electromagnetic energy beams to produce images of internal tissues, bones, and organs onto film.

• Ultrasound (also called sonography). A diagnostic imaging technique that uses high-frequency sound waves and a computer to create images of blood vessels, tissues, and organs. Ultrasounds are used to view internal organs as they function, and to assess blood flow through various vessels.

• Lymph node biopsy. A procedure performed to remove tissue or cells from a lymph node in the body for examination under a microscope.

• Spinal tap/lumbar puncture. A special hollow needle is placed into the lower back, into the spinal canal. This is the area around the spinal cord. The pressure in the spinal canal and brain can then be measured. A small amount of cerebral spinal fluid (CSF) can be removed and sent for testing to determine if there is an infection, leukemia cells in the CSF, or or other problems. CSF is the fluid that bathes the brain and spinal cord.

Treatment for acute and chronic leukemias

Specific treatment for acute and chronic leukemias will be determined by your doctor based on:

• Your age, overall health, and medical history

• The type of leukemia and other factors, such as chromosome changes in the cells

• Extent of the disease

• Your tolerance for specific medications, procedures, or therapies

• Expectations for the course of the disease

• Your opinion or preference

Treatment may include:

• Chemotherapy or targeted therapy medications

• Radiation therapy

• Bone marrow or peripheral blood stem cell transplantation

• Biological therapy, which uses the body's immune system to fight cancer

• Surgery

• Blood transfusion (red blood cells, platelets)

• Medications to prevent or treat damage to other systems of the body caused by leukemia treatment