Acute Myelocytic Leukemia Health Article

Causes and symptoms

AML is neither contagious nor inherited. However, people who suffer from certain genetic disorders, such as Fanconi anemia, Klinefelter syndrome, Patau syndrome, Bloom syndrome, and Down syndrome, are at greater risk of developing AML than the general population. A child with Down syndrome is roughly 14 times as likely as the average child to develop leukemia.

Any person who has been exposed to radiation at high doses is at heightened risk of developing AML, as are people exposed to benzene, a chemical used in the manufacture of plastics, rubber, medicines, and certain other chemicals. Another group of people at increased risk for developing AML are those who have been treated for cancer with certain medicines, for example, chloramphenicol, phenylbutazone, chloroquine, and methoxypsoralen.

The symptoms of AML are generally vague and non-specific. A patient may experience all or some of the following symptoms:

• weakness or chronic fatigue
• fever of unknown origin
• shortness of breath
• weight loss that is not due to dieting or exercise
• frequent bacterial or viral infections
• headaches
• skin rash
• non-specific bone pain
• easy bruising
• bleeding from gums or nose
• blood in urine or stools
• enlarged lymph nodes and/or spleen
• abdominal fullness

A small minority of patients with AML have a tumor of leukemic cells at diagnosis. Such a tumor may appear in the lung, breast, brain, uterus, ovary, stomach, prostate, or certain other places in the body.

Some children with AML present to their doctor with very few symptoms, while other children present with severe symptoms. Anemia is usually present. The symptoms of the anemia may include fatigue, dizziness, headache, paleness of the skin, or, infrequently, congestive heart failure. Easy bruising, bleeding gums, and nosebleeds may be present, as may fever. There may be swollen gums, bone pain or joint pain, or, rarely, an actual tumor. Some infants with AML have skin disorders.

Diagnosis

Like all cancers, acute leukemias are best treated when found early. There are no screening tests available.

A thorough diagnostic evaluation should be conducted. This is important because the doctor must determine more than whether or not AML is present. If it is suspected, has it affected the general health of the patient? Is the patient capable of undergoing rigorous treatment?

A doctor who suspects leukemia may start by obtaining a thorough medical history. The doctor may then conduct a very thorough physical examination to look for enlarged lymph nodes in the neck, underarm, and pelvic region. Swollen gums, enlarged liver or spleen, bruises, or pinpoint red rashes all over the body are among the signs of the disease. In addition, the physician may examine the teeth and look for dental abscesses, and may explore whether back pain is present.

Urine and blood tests may be ordered to check for microscopic amounts of blood in the urine and to obtain a complete differential blood count. This count will give the numbers and percentages of the different cells found in the blood. An abnormal blood test might suggest leukemia. Patients suffering from AML may have high leukocyte counts and typically have low counts of both red blood cells and platelets. Many patients with AML have low counts of all of the major components of the blood. A microscopic exploration of the blood will usually show that leukemic blast cells are present. However, the diagnosis has to be confirmed by more specific tests.

The doctor may perform a bone marrow aspiration and biopsy to confirm the diagnosis of leukemia. Aspiration involves the withdrawal of a liquid sample of marrow. During the biopsy, a cylindrical piece of bone and marrow is removed. The tissue is generally taken out of the hipbone. These samples are sent to the laboratory for examination. In addition to diagnosis, the aspiration and biopsy may be repeated during the treatment phase of the disease to see if the leukemia is responding to therapy.

A chest x ray is taken. Cardiac tests, including an electrocardiogram, are conducted. The patient is examined for possible infection. These diagnostic procedures often disclose bleeding in the stomach or intestines, and there may be bleeding in the lungs, brain, or eyes. Anemia is often present and may be severe.

Cytogenetic studies, which examine the number and shape of the chromosomes in the DNA of individual blast cells, should be conducted in addition to the immunophenotyping of cells of the bone marrow. This procedure involves applying various stains to the marrow cells. These stains help doctors identify some of the proteins lying on the surface of the cells.

A spinal tap (lumbar puncture) is another procedure the doctor may order to diagnose leukemia. In this procedure, a small needle is inserted into the spinal cavity in the lower back to withdraw some cerebrospinal fluid and to look for leukemic cells.

Standard imaging tests such as x rays may be used to check whether the leukemic cells have invaded other areas of the body, such as the bones, chest, kidneys, abdomen, or brain. Other tests, such as computed tomography scans (CT scans), magnetic resonance imaging (MRI), or gallium scans, are not typical for AML but may also be performed.

Children with AML are given most of the same studies used for adults.