Key Points for This Section

Leukemia and other diseases of the blood and bone marrow may affect red blood cells, white blood cells, and platelets. Childhood acute myeloid leukemia (AML) is a type of cancer in which the bone marrow makes a large number of abnormal blood cells. Other myeloid diseases can affect the blood and bone marrow. Chronic myelogenous leukemia Juvenile myelomonocytic leukemia Transient myeloproliferative disorder Myelodysplastic syndromes The risk factors for developing childhood AML, childhood CML, JMML, TMD, and MDS are similar. Possible signs of childhood AML, childhood CML, JMML, or MDS include fever, feeling tired, and easy bleeding or bruising. Tests that examine the blood and bone marrow are used to detect (find) and diagnose childhood AML, childhood CML, JMML, TMD, and MDS. Certain factors affect prognosis (chance of recovery) and treatment options.

Leukemia and other diseases of the blood and bone marrow may affect red blood cells, white blood cells, and platelets.

Normally, the bone marrow makes blood stem cells (immature cells) that develop into mature blood cells over time. A blood stem cell may become a myeloid stem cell or a lymphoid stem cell. The lymphoid stem cell develops into a white blood cell. The myeloid stem cell develops into one of three 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.

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Blood cell development. A blood stem cell goes through several steps to become a red blood cell, platelet, or white blood cell.

Childhood acute myeloid leukemia (AML) is a type of cancer in which the bone marrow makes a large number of abnormal blood cells.

Cancers that are acute usually get worse quickly if they are not treated. Cancers that are chronic usually get worse slowly. Acute myeloid leukemia (AML) is also called acute myelogenous leukemia, acute myeloblastic leukemia, acute granulocytic leukemia, or acute nonlymphocytic leukemia.

In AML, the myeloid stem cells usually develop into a type of immature white blood cell called myeloblasts (or myeloid blasts). The myeloblasts, or leukemia cells, in AML are abnormal and do not become healthy white blood cells. The leukemia cells can build up in the blood and bone marrow so there is less room for healthy white blood cells, red blood cells, and platelets. When this happens, infection, anemia, or easy bleeding may occur. The leukemia cells can spread outside the blood to other parts of the body, including the central nervous system (brain and spinal cord), skin, and gums. Sometimes leukemia cells form a solid tumor called a granulocytic sarcoma or chloroma.

There are subtypes of AML based on the type of blood cell that is affected. The treatment of AML is different when it is a subtype called acute promyelocytic leukemia (APL) or when the child has Down syndrome.

Other myeloid diseases can affect the blood and bone marrow.

Chronic myelogenous leukemia

In chronic myelogenous leukemia (CML), too many bone marrow stem cells develop into a type of white blood cell called granulocytes. Some of these bone marrow stem cells never become mature white blood cells. These are called blasts. Over time, the granulocytes and blasts crowd out the red blood cells and platelets in the bone marrow. CML is rare in children.

Juvenile myelomonocytic leukemia

Juvenile myelomonocytic leukemia (JMML) is a rare childhood cancer that occurs more often in children around the age of 2 years. In JMML, too many bone marrow stem cells develop into 2 types of white blood cells called myelocytes and monocytes. Some of these bone marrow stem cells never become mature white blood cells. These immature cells, called blasts, are unable to do their usual work. Over time, the myelocytes, monocytes, and blasts crowd out the red blood cells and platelets in the bone marrow. When this happens, infection, anemia, or easy bleeding may occur.

Transient myeloproliferative disorder

Transient myeloproliferative disorder (TMD) is a disorder of the bone marrow that can develop in newborns who have Down syndrome. This disorder usually goes away on its own within the first 3 weeks of life. Infants who have Down syndrome and TMD have an increased chance of developing AML before the age of 3 years.

Myelodysplastic syndromes

In myelodysplastic syndromes (MDS), the bone marrow makes too few red blood cells, white blood cells, and platelets. These blood cells may not mature and enter the blood. The treatment for MDS depends on how much lower than normal the number of red blood cells, white blood cells, or platelets is. MDS may progress to AML.

This summary is about childhood AML, childhood CML, JMML, TMD, and MDS. See the following PDQ summaries for more information about other types of leukemia and diseases of the blood and bone marrow:

• Adult Acute Myeloid Leukemia Treatment ¹
• Chronic Myelogenous Leukemia Treatment ²
• Adult Acute Lymphoblastic Leukemia Treatment ³
• Childhood Acute Lymphoblastic Leukemia Treatment ⁴
• Chronic Lymphocytic Leukemia Treatment ⁵
• Hairy Cell Leukemia Treatment ⁶
• Myelodysplastic Syndromes Treatment ⁷
• Myelodysplastic and Myeloproliferative Diseases Treatment ⁸

The risk factors for developing childhood AML, childhood CML, JMML, TMD, and MDS are similar.

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. People who think they may be at risk should discuss this with their doctor. Possible risk factors for childhood AML, childhood CML, JMML, TMD, and MDS include the following:

• Having a brother or sister, especially a twin, with leukemia.
• Being Hispanic.
• Being exposed to cigarette smoke or alcohol before birth.
• Having a history of MDS (also called preleukemia) or aplastic anemia.
• Past treatment with chemotherapy or radiation therapy.
• Being exposed to ionizing radiation or chemicals such as benzene.
• Having certain genetic disorders, such as Down syndrome, Fanconi anemia, neurofibromatosis type 1, or Noonan syndrome.

Possible signs of childhood AML, childhood CML, JMML, or MDS include fever, feeling tired, and easy bleeding or bruising.

These and other symptoms may be caused by childhood AML, childhood CML, JMML, or MDS. Other conditions may cause the same symptoms. A doctor should be consulted if any of the following problems occur:

• Fever with or without an infection.
• Night sweats.
• Shortness of breath.
• Weakness or feeling tired.
• Easy bruising or bleeding.
• Petechiae (flat, pinpoint spots under the skin caused by bleeding).
• Pain in the bones or joints.
• Pain or feeling of fullness below the ribs.
• Painless lumps in the neck, underarm, stomach, groin, or other parts of the body. When seen in childhood AML, these lumps, called leukemia cutis, may be blue or purple.
• Painless lumps that are sometimes around the eyes. These lumps, called chloromas, are sometimes seen in childhood AML and may be blue-green.
• An eczema -like skin rash.

The symptoms of TMD may include the following:

• Swelling all over the body.
• Shortness of breath.
• Trouble breathing.
• Weakness or feeling tired.
• Pain below the ribs.

Tests that examine the blood and bone marrow are used to detect (find) and diagnose childhood AML, childhood CML, JMML, TMD, and MDS.

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 sample made up of red blood cells.

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  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.

• 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 makes it.
• 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.
• Peripheral blood smear: A procedure in which a sample of blood is checked for blast cells, number and kinds of white blood cells, number of platelets, and changes in the shape of the blood cells.
• Biopsy: The removal of cells or tissues so they can be viewed under a microscope by a pathologist to check for signs of cancer. Biopsies that may be done for childhood AML include the following:
  • 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.

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    Bone marrow aspiration and biopsy. After a small area of skin is numbed, a Jamshidi needle (a long, hollow needle) is inserted into the patient’s hip bone. Samples of blood, bone, and bone marrow are removed for examination under a microscope.

  • Tumor biopsy: A biopsy of a chloroma may be done.
  • Lymph node biopsy: The removal of all or part of a lymph node.
• Cytogenetic analysis: A laboratory test in which cells in a sample of blood or bone marrow are viewed under a microscope to look for certain changes in the chromosomes.
• Immunophenotyping: A process used to identify cells, based on the types of antigens or markers on the surface of the cell, that may include special staining of the blood and bone marrow cells. This process is used to diagnose the subtype of AML by comparing the cancer cells to normal cells of the immune system.
• Lumbar puncture: A procedure used to collect cerebrospinal fluid from the spinal column. This is done by placing a needle into the spinal column. This procedure is also called an LP or spinal tap.

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  Lumbar puncture. A patient lies in a curled position on a table. After a small area on the lower back is numbed, a spinal needle (a long, thin needle) is inserted into the lower part of the spinal column to remove cerebrospinal fluid (CSF, shown in blue). The fluid may be sent to a laboratory for testing.

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

The prognosis (chance of recovery) and treatment options for childhood AML depend on the following:

• The age of the child at diagnosis.
• Number of white blood cells in the blood at diagnosis.
• Whether the AML was caused by previous anticancer treatment.
• The subtype of AML.
• Whether there are certain chromosomal changes in the leukemia cells.
• Whether the child has Down syndrome. Most children with AML and Down syndrome can be cured of their leukemia.
• How well the leukemia responds to initial treatment.
• Whether the AML is newly diagnosed or has recurred (come back) after being treated.
• The length of time since treatment ended, for AML that has recurred.

The prognosis and treatment options for childhood CML depend on how long it has been since the patient was diagnosed and how many blast cells are in the blood.

The prognosis (chance of recovery) and treatment options for JMML depend on the following:

• The age of the child at diagnosis.
• How many red blood cells, white blood cells, or platelets are in the blood.
• Whether the JMML is untreated or has recurred after treatment.

The prognosis (chance of recovery) and treatment options for MDS depend on the following:

• Whether the MDS was caused by previous cancer treatment.
• How low the numbers of red blood cells, white blood cells, or platelets are.
• Whether the MDS is untreated or has recurred after treatment.

Glossary Terms

Not normal. An abnormal lesion or growth may be cancerous, premalignant (likely to become cancer), or benign.

Symptoms or signs that begin and worsen quickly; not chronic.

A quickly progressing disease in which too many immature white blood cells (not lymphocytes) are found in the blood and bone marrow. Also called acute myeloblastic leukemia, acute myelogenous leukemia, acute nonlymphocytic leukemia, AML, and ANLL.

An aggressive (fast-growing) type of acute myeloid leukemia in which there are too many immature blood-forming cells in the blood and bone marrow. It is usually marked by an exchange of parts of chromosomes 15 and 17. Also called APL and promyelocytic leukemia.

A condition in which the number of red blood cells is below normal.

A substance that causes the immune system to make a specific immune response.

A condition in which the bone marrow is unable to produce blood cells.

A chemical that is used widely by the chemical industry, and is also found in tobacco smoke, vehicle emissions, and gasoline fumes. Exposure to benzene may increase the risk of developing leukemia.

The removal of cells or tissues for examination by a pathologist. The pathologist may study the tissue under a microscope or perform other tests on the cells or tissue. There are many different types of biopsy procedures. The most common types include: (1) incisional biopsy, in which only a sample of tissue is removed; (2) excisional biopsy, in which an entire lump or suspicious area is removed; and (3) needle biopsy, in which a sample of tissue or fluid is removed with a needle. When a wide needle is used, the procedure is called a core biopsy. When a thin needle is used, the procedure is called a fine-needle aspiration biopsy.

An immature blood cell.

A tissue with red blood cells, white blood cells, platelets, and other substances suspended in fluid called plasma. Blood takes oxygen and nutrients to the tissues, and carries away wastes.

A procedure in which a sample of blood is examined to measure the amounts of certain substances made in the body. An abnormal amount of a substance can be a sign of disease in the organ or tissue that produces it.

A mass of blood that forms when blood platelets, proteins, and cells stick together. When a blood clot is attached to the wall of a blood vessel, it is called a thrombus. When it moves through the bloodstream and blocks the flow of blood in another part of the body, it is called an embolus.

The soft, sponge-like tissue in the center of most bones. It produces white blood cells, red blood cells, and platelets.

The removal of a small sample of bone marrow (usually from the hip) through a needle for examination under a microscope.

The removal of a sample of tissue from the bone marrow with a needle for examination under a microscope.

The individual unit that makes up the tissues of the body. All living things are made up of one or more cells.

The brain and spinal cord. Also called CNS.

The fluid that flows in and around the hollow spaces of the brain and spinal cord, and between two of the meninges (the thin layers of tissue that cover and protect the brain and spinal cord). Cerebrospinal fluid is made by tissue called the choroid plexus in the ventricles (hollow spaces) in the brain. Also called CSF.

Treatment with drugs that kill cancer cells.

An x-ray of the structures inside the chest. An x-ray is a type of high-energy radiation that can go through the body and onto film, making pictures of areas inside the chest, which can be used to diagnose disease.

A malignant, green-colored tumor of myeloid cells (a type of immature white blood cell). This tumor is usually associated with myelogenous leukemia. Also called granulocytic sarcoma.

Part of a cell that contains genetic information. Except for sperm and eggs, all human cells contain 46 chromosomes.

A disease or condition that persists or progresses over a long period of time.

A slowly progressing disease in which too many white blood cells (not lymphocytes) are made in the bone marrow. Also called chronic granulocytic leukemia, chronic myeloid leukemia, and CML.

A test to check the number of red blood cells, white blood cells, and platelets in a sample of blood. Also called blood cell count and CBC.

The study of chromosomes and chromosomal abnormalities.

The process of identifying a disease, such as cancer, from its signs and symptoms.

In medicine, a disturbance of normal functioning of the mind or body. Disorders may be caused by genetic factors, disease, or trauma.

A disorder caused by the presence of an extra chromosome 21 and characterized by mental retardation and distinguishing physical features.

A group of conditions in which the skin becomes inflamed, forms blisters, and becomes crusty, thick, and scaly. Eczema causes burning and itching, and may occur over a long period of time. Atopic dermatitis is the most common type of eczema.

A rare inherited disorder in which the bone marrow does not make blood cells. It is usually diagnosed in children between 2 and 15 years old. Symptoms include frequent infections, easy bleeding, and extreme tiredness. People with Fanconi anemia may have a small skeleton and brown spots on the skin. They also have an increased risk of developing certain types of cancer.

An increase in body temperature above normal (98.6 degrees F), usually caused by disease.

Inherited; having to do with information that is passed from parents to offspring through genes in sperm and egg cells.

A type of white blood cell that fights bacterial infection. Neutrophils, eosinophils, and basophils are granulocytes.

A malignant, green-colored tumor of myeloid cells (a type of immature white blood cell). This tumor is usually associated with myelogenous leukemia. Also called chloroma.

The area where the thigh meets the abdomen.

The substance inside red blood cells that binds to oxygen in the lungs and carries it to the tissues.

A process used to identify cells, based on the types of antigens or markers on the surface of the cell. This process is used to diagnose specific types of leukemia and lymphoma by comparing the cancer cells to normal cells of the immune system.

Invasion and multiplication of germs in the body. Infections can occur in any part of the body and can spread throughout the body. The germs may be bacteria, viruses, yeast, or fungi. They can cause a fever and other problems, depending on where the infection occurs. When the body’s natural defense system is strong, it can often fight the germs and prevent infection. Some cancer treatments can weaken the natural defense system.

A type of radiation made (or given off ) by x-ray procedures, radioactive substances, rays that enter the Earth's atmosphere from outer space, and other sources. At high doses, ionizing radiation increases chemical activity inside cells and can lead to health risks, including cancer.

A rare form of childhood leukemia in which cancer cells often spread into tissues such as the skin, lung, and intestines. Also called JMML.

Cancer that starts in blood-forming tissue such as the bone marrow and causes large numbers of blood cells to be produced and enter the bloodstream.

A procedure in which a thin needle called a spinal needle is put into the lower part of the spinal column to collect cerebrospinal fluid or to give drugs. Also called spinal tap.

A rounded mass of lymphatic tissue that is surrounded by a capsule of connective tissue. Lymph nodes filter lymph (lymphatic fluid), and they store lymphocytes (white blood cells). They are located along lymphatic vessels. Also called lymph gland.

Referring to lymphocytes, a type of white blood cell. Also refers to tissue in which lymphocytes develop.

A diagnostic indication that disease may develop.

A type of white blood cell.

A group of diseases in which the bone marrow does not make enough healthy blood cells. Also called preleukemia and smoldering leukemia.

Having to do with or resembling the bone marrow. May also refer to certain types of hematopoietic (blood-forming) cells found in the bone marrow. Sometimes used as a synonym for myelogenous; for example, acute myeloid leukemia and acute myelogenous leukemia are the same disease.

A group of slow growing blood cancers, including chronic myelogenous leukemia, in which large numbers of abnormal red blood cells, white blood cells, or platelets grow and spread in the bone marrow and the peripheral blood.

A rare genetic condition that causes brown spots and tumors on the skin, freckling in skin areas not exposed to the sun, tumors on the nerves, and developmental changes in the nervous system, muscles, bone, and skin. Also called NF1.

A part of the body that performs a specific function. For example, the heart is an organ.

A colorless, odorless gas. It is needed for animal and plant life. Oxygen that is breathed in enters the blood from the lungs and travels to the tissues.

A doctor who identifies diseases by studying cells and tissues under a microscope.

PDQ is an online database developed and maintained by the National Cancer Institute. Designed to make the most current, credible, and accurate cancer information available to health professionals and the public, PDQ contains peer-reviewed summaries on cancer treatment, screening, prevention, genetics, complementary and alternative medicine, and supportive care; a registry of cancer clinical trials from around the world; and directories of physicians, professionals who provide genetics services, and organizations that provide cancer care. Most of this information, and more specific information about PDQ, can be found on the NCI's Web site at http://www.cancer.gov/cancertopics/pdq. Also called Physician Data Query.

A procedure in which a sample of blood is viewed under a microscope to count different circulating blood cells (red blood cells, white blood cells, platelets, etc.) and see whether the cells look normal.

Pinpoint, unraised, round red spots under the skin caused by bleeding.

An exam of the body to check for general signs of disease.

A type of blood cell that helps prevent bleeding by causing blood clots to form. Also called thrombocyte.

A group of diseases in which the bone marrow does not make enough healthy blood cells. Also called myelodysplastic syndromes and smoldering leukemia.

The likely outcome or course of a disease; the chance of recovery or recurrence.

A molecule made up of amino acids that are needed for the body to function properly. Proteins are the basis of body structures such as skin and hair and of substances such as enzymes, cytokines, and antibodies.

The use of high-energy radiation from x-rays, gamma rays, neutrons, protons, and other sources to kill cancer cells and shrink tumors. Radiation may come from a machine outside the body (external-beam radiation therapy), or it may come from radioactive material placed in the body near cancer cells (internal radiation therapy). Systemic radiation therapy uses a radioactive substance, such as a radiolabeled monoclonal antibody, that travels in the blood to tissues throughout the body. Also called irradiation and radiotherapy.

Cancer that has recurred (come back), usually after a period of time during which the cancer could not be detected. The cancer may come back to the same place as the original (primary) tumor or to another place in the body. Also called recurrence.

A cell that carries oxygen to all parts of the body. Also called erythrocyte and RBC.

Something that may increase the chance of developing a disease. Some examples of risk factors for cancer include age, a family history of certain cancers, use of tobacco products, certain eating habits, obesity, lack of exercise, exposure to radiation or other cancer-causing agents, and certain genetic changes.

An abnormal mass of tissue that usually does not contain cysts or liquid areas. Solid tumors may be benign (not cancerous), or malignant (cancerous). Different types of solid tumors are named for the type of cells that form them. Examples of solid tumors are sarcomas, carcinomas, and lymphomas. Leukemias (cancers of the blood) generally do not form solid tumors.

The bones, muscles, tendons, and other tissues that reach from the base of the skull to the tailbone. The spinal column encloses the spinal cord and the fluid surrounding the spinal cord. Also called backbone, spine, and vertebral column.

A column of nerve tissue that runs from the base of the skull down the back. It is surrounded by three protective membranes, and is enclosed within the vertebrae (back bones). The spinal cord and the brain make up the central nervous system, and spinal cord nerves carry most messages between the brain and the rest of the body.

A cell from which other types of cells develop. For example, blood cells develop from blood-forming stem cells.

An organ that is part of the digestive system. The stomach helps digest food by mixing it with digestive juices and churning it into a thin liquid.

An indication that a person has a condition or disease. Some examples of symptoms are headache, fever, fatigue, nausea, vomiting, and pain.

A group or layer of cells that work together to perform a specific function.

An abnormal mass of tissue that results when cells divide more than they should or do not die when they should. Tumors may be benign (not cancerous), or malignant (cancerous). Also called neoplasm.

Refers to a blood cell that does not contain hemoglobin. White blood cells include lymphocytes, neutrophils, eosinophils, macrophages, and mast cells. These cells are made by bone marrow and help the body fight infections and other diseases. Also called WBC.

A type of high-energy radiation. In low doses, x-rays are used to diagnose diseases by making pictures of the inside of the body. In high doses, x-rays are used to treat cancer.