Just Diagnosed

When someone is suspected of having leukemia, a number of tests are performed to evaluate the child. The initial test will be a blood test called the complete blood count (CBC). A pediatrician or family doctor may order blood tests before referring a child to a specialist called a pediatric hematologist or pediatric oncologist. Those tests are often repeated when the child sees the specialist.

Although leukemia cells may be found in the blood, most commonly, the diagnosis and classification of leukemia are confirmed by looking at a sample of bone marrow under the microscope. This sample is obtained by performing a bone marrow aspirate.

An additional test that may be performed along with the bone marrow aspirate is the bone marrow biopsy.

Determining the Extent of Disease

Since ALL is a cancer of the blood, it is not "staged" in the way solid tumors are. By nature, leukemia is widespread at diagnosis, but this does not affect successful treatment. However, leukemia cells can also be present in the spinal fluid, which is known as Central Nervous System (CNS) disease. A special test known as a spinal tap or lumbar puncture will be performed to obtain fluid for examination.

In addition to being present in the bone marrow and blood, ALL can spread to areas that are part of the blood system, causing enlargement of organs. It can affect many sites, but the most common ones are:
  • Lymph nodes (glands)
  • Liver
  • Spleen
  • Testicles
  • Central nervous system
Involvement of organs other than the CNS or testicles usually has no bearing on the type of treatment given or the chances for cure.

Causes of ALL

Researchers have been looking for causes of ALL for over 40 years. Many studies identified what seemed like clues at the time, but they were not confirmed in later studies. Even though one or even several studies may find a link between something and risk of ALL, there are scientific criteria that must be met before it can be concluded that the something really causes ALL.Researchers know that the following things DO NOT cause ALL.
  • Electromagnetic fields, such as those from power lines and electrical appliances
  • Mother’s smoking during pregnancy
  • Mother’s consumption of alcohol during pregnancy
  • Ultrasound (sonograms) during pregnancy
  • Vitamin K given to newborns to prevent bleeding
For patients with acute lymphoblastic leukemia, the following is known

Genetic Conditions

Children with some genetic syndromes are more likely to develop ALL than other children. The syndromes are Down syndrome, neurofibromatosis, Schwachman syndrome, Bloom syndrome and ataxia telangiectasia. Babies with these genetic conditions are more at risk for ALL, but these account for only a small fraction of total ALL cases. These syndromes usually require medical care, so parents would know if their child had one of them.

Ionizing Radiation (X-rays)

Early studies showed there was an increased risk of ALL when a baby was x-rayed while in its mother's womb. Today, however, researchers believe that x-rays during pregnancy cause few, if any, cases of ALL because pregnant women are not x-rayed often and the amount of radiation used in x-rays is much, much lower than it was years ago. Children who receive x-rays to diagnose a medical condition, such as a broken bone or tooth decay are NOT at increased risk to develop ALL.

Race and Economic Status

Researchers have noted some patterns in the occurrence of childhood ALL. Hispanic children in the U.S. are more likely than non-Hispanic Caucasian children to develop ALL. Caucasian children are more likely than African American children to develop ALL. How the occurrence of ALL in Asian-American children compared to that in other children is not known. For reasons that are not yet known, children from wealthier countries are more likely to develop ALL than children from poor countries.


In children diagnosed with ALL, there is a slightly higher incidence in boys than girls.

High Birth Weight

Most studies show that babies with high birth weight (more than 4,000 grams, which is 8 lbs, 8 oz.) are at slightly increased risk of developing ALL. Currently, it is not known why high birth weight increases the risk of ALL.

Last updated September, 2011

About Acute Lymphoblastic Leukemia
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After Treatment for Acute Lymphoblastic Leukemia