Acute Myelogenous Leukemia Facts

Acute myeloid leukemia (AML) is the second most common type of leukemia in children. The first is acute lymphoblastic leukemia (ALL). AML forms in the bone marrow. These cancerous cells divide rapidly and do not die easily. They eventually crowd out normal, healthy blood cells and prevent them from being produced. AML can accumulate in the blood stream and organs such as the lymp nodes, brain, liver, kidneys, ovaries, testicles, and skin. If AML forms a tumor it is called a chloroma.

 

Symptoms

AML symptoms are similar to other leukemias as well as other noncancerous conditions. So it’s important to have your child seen by a doctor if these symptoms occur:

• Fever, which may be a sign of infection
• Easy bruising or bleeding, even from small injuries
• Petechiae, which are pinpoint spots of blood under the skin caused by tiny broken blood vessels
• Bone or joint pain, from leukemic cells collecting there
• Painless lumps in the neck, underarm, stomach, groin and possibly around the eyes
• Pain and fullness under the ribs, from enlargement of the liver and spleen
• Weakness and fatigue
• Loss of appetite
• Shortness of breath or coughing, from swelling of the thymus (a gland in the neck that is related to the immune system)

Diagnosis

To find out whether your child has leukemia, your child’s doctor will first do a thorough physical exam and ask about your child’s health history. Next the doctor will probably perform a series of blood tests to tell whether any blood cells are unhealthy and, if so, which type. Common blood tests to check for leukemia include the following:

• Complete blood count, or CBC: to determine how many cells of each type are circulating in the blood stream
• Peripheral blood smear: to look at the appearance of the blood cells
• Blood chemistry: to look for chemicals in the blood that can be abnormal in people who have cancer

For a clear diagnosis, doctors may need to perform a bone marrow aspirate and sometimes a bone marrow biopsy. A small area of skin over the pelvis (the bone that makes up part of the hip) will be cleaned and numbed. Then a teaspoon of bone marrow will be withdrawn with a needle (aspirate). Your child will receive medicines to help with any pain or discomfort associated with this procedure.

 

More specific laboratory tests of the blood can give your child’s doctors more information about the type of cells affected. These include tests that identify proteins on the surface of the leukemic cells and tests that look at the arrangement of chromosomes in the leukemic cells.

Doctors may do further tests to detect whether the cancer has spread to parts of your child’s body beyond the blood. For instance, a lumbar puncture, or spinal tap, may be done to remove cerebrospinal fluid (CSF) from the spinal column using a needle. If there are leukemic cells in the CSF, doctors know the brain and spinal cord may be affected by the cancer. A chest X-ray can provide a view into the chest area. A biopsy of the testicles, ovaries or skin helps doctors determine whether the cancer has spread there.

Based on what they learn through their diagnostic tests, doctors may classify your child’s leukemia into a category. The categories are designed to help doctors select the most appropriate treatment for each child.

With AML, there are no risk groups assigned at the time of diagnosis. Certain features of the leukemia can make the disease higher risk. These features include poor response to initial therapy and some chromosome abnormalities of the leukemia.

 

AML Sub Types

 

The World Health Organization (WHO) classification for AML subtypes is:

 

Acute myeloid leukemia with recurrent genetic abnormalities

• Aute myeloid leukemia with t(8;21)(q22;q22), AML1/ETO)
• Acute myeloid leukemia with abnormal bone marrow eosinophils and inv(16)(p13q22) or t(16;16)(p13;q22), (CBFß/MYH11)
• Acute promyelocytic leukemia with t(15;17)(q22;q12), (PML/RARa) and variants
• Acute myeloid leukemia with 11q23 (MLL) abnormalities

Acute myeloid leukemia with multilineage dysplasia

• Following MDS or MDS/MPD
• Without antecedent MDS or MDS/MPD, but with dysplasia in at least 50% of cells in 2 or more myeloid lineages

Acute myeloid leukemia and myelodysplastic syndromes, therapy related

• Alkylating agent/radiation-related type
• Topoisomerase II inhibitor-related type (some may be lymphoid)
• Others

Acute myeloid leukemia, not otherwise categorized

• Acute myeloid leukemia, minimally differentiated (previously called M0)
• Acute myeloid leukemia without maturation (previously called M1)
• Acute myeloid leukemia with maturation (previously called M2)
• Acute myelomonocytic leukemia (previously called M4)
• Acute monoblastic/acute monocytic leukemia (previously called M5)
• Acute erythroid leukemia (erythroid/myeloid and pure erythroleukemia) (previously called M6)
• Acute megakaryoblastic leukemia (previously called M7)
• Acute basophilic leukemia
• Acute panmyelosis with myelofibrosis
• Myeloid sarcoma

[Data provided by American Society of Clinical Oncology]

 

Risk Factors

Doctors do not know what causes AML in children. Some children with Down Syndrome are at risk for the first three years of life, but it is not known why. Children who have a sibiling with AML, especially twins, are at higher risk for AML.