Resources and information for parents of children with cancer . . . by parents of children with cancer.

Leukemia

On this site: Warning Signs of Childhood Cancer: Leukemia

Leukemia is a cancer of the bone marrow, the spongy center of the bones that makes blood cells. In leukemia, abnormal white blood cells divide out of control and crowd out the normal cells in the bloodstream. The abnormal white blood cells are not mature, and therefore cannot carry out their infection-fighting function in the blood. These cells crowd out healthy white blood cells, as well as the red blood cells which carry oxygen to the body and the platelets which cause the blood to clot.

What are the different types of childhood leukemia?

The most common type of leukemia in children is acute lymphocytic (or lymphoblastic) leukemia or ALL, which is further characterized as pre-B, B, or T-cell ALL. Childhood acute myeloid leukemia or AML is less common. "Acute" means that the diseases progress rapidly. The chronic forms of these leukemias, CLL and CML respectively, are seen almost solely in adults. In general, acute leukemias are most prevalent in children and are therefore often referred to as "childhood leukemias".

About 5% of childhood leukemias are distinct types of chronic myeloid leukemias. Juvenile myelomonocytic leukemia (JMML, NCI PDQ) occurs primarily in children aged 2 or under. Acute promyelocytic leukemia (APL, NCI PDQ) is a distinct subtype of AML. A good starting point for research into these and other less common childhood leukemias is on the cancer.gov myeloid leukemias page.

Types of white blood cells

White blood cells - the blood cells that grow out of control in leukemia - are the cells that fight infection. Blood contains three types of cells:

All blood cells originate in the bone marrow. In fact, they all develop from one special type of cell, called a stem cell.

White blood cells come in several types, including:

In acute lymphocytic leukemias, the B- or T-lymphocytes are growing out of control. In acute myelogenous leukemias, the granulocytes are growing out of control.

In all of the leukemias, immature white cells crowd out the good cells. Since they crowd out the red blood cells, a person with leukemia is anemic, without enough red blood cells to carry the necessary oxygen or energy to the body. That's why fatigue is a sign of leukemia. The leukemia cells also crowd out the platelets, so if a person with leukemia is cut, the bleeding does not stop as readily. They also bruise easier. Since the blasts are immature, non-functioning infection fighting cells, a person with leukemia is easily susceptible to infection.

If you are interested in more information on blood cells, follow the links below for in-depth, technical information.

Treatment for childhood leukemias

ALL. The primary treatment for newly diagnosed ALL is combination chemotherapy. Radiation and bone marrow transplantation may be used in some cases. Treatment begins with an intense treatment called "induction" with a combination of several chemotherapy drugs, usually cytosine arabinoside, vincristine, prednisone, L-asparaginase, and daunorubicin. The goal of induction is to kill most of the leukemia cells; most patients do not have any leukemic cells in the bone marrow at the end of induction. (At least, not detectable in a light-microscopical examination of stained bone marrow smear.) The next phase is called "consolidation" in which a different combination of drugs is administered, usually methotrexate, cyclophosphamide, cytosine arabinoside, mercaptopurine, and prednisone. "Maintenance" follows, in which the chemotherapy is lessened to a few of the drugs administered less frequently. Maintenance is generally well tolerated by the patient. Often a period of maintenance is followed by another cycle of induction-consolidation, called "re-intensification". Total therapy lasts from two to three years. Detailed information on this web site:

AML. In general, newly diagnosed AML is initially treated more aggressively than is ALL. Intensive chemotherapy followed by bone marrow transplantation is becoming the first treatment chosen, especially when a suitable donor is available. After the intensive chemotherapy and/or bone marrow transplant, children with AML do not go on maintenance; studies have shown that AML children in remission have had as much chemotherapy as their bodies can tolerate, and additional maintenance chemotherapy does not benefit them.

Chronic myeloid leukemias. As in AML, intensive chemotherapy and/or BMT are generally employed. Currently (2005), imatinib mesylate (Gleevec) is being studied in clinical trials. Chronic leukemias have three clinical phases: chronic, accelerated, and blast crisis. Prognosis depends on the clinical phase of the disease.

Relapsed leukemia. Relapse, or recurrence of leukemia, can occur anytime during therapy or after completion of treatment. Generally, it is more difficult to cure a child after relapse of the leukemia; relapse during or soon after the completion of treatment is considered less favorable than relapse a year or several years after treatment. Treatment depends on the site of relapse, whether it is in the bone marrow, central nervous system, testes, or other locations. Aggressive chemotherapy and radiation treatment, often followed bone marrow transplantation, are used to treat relapse of childhood leukemia.

New Treatments

What's on the horizon for leukemia treatment? The following organization talks about new treatments:

The big news (early 2000s) for the treatment of CML (and maybe Ph+ ALL) is STI-571. Brian Druker (Oregon Health Sciences University in Portland) is the Leukemia and Lymphoma Society doctor prominent in this research.

In 2004, ara G entered the treatment plans for T-cell ALL. Clofarabine (2005) shows promise for refractory (relapsed) ALL. More information in an essay on your author's private web site:

Statistics

Ped-Onc Resources for Leukemia

The following ped-onc resource lists have appropriate sections for parents of children with leukemia:

Links to More Information

The following web sites provide good, general information on lymphomas cancers and their treatment.

General Information on Leukemia and Leukemia Research

Technical Information

General Disclaimer

These pages are intended for informational purposes only and are not intended to render medical advice. The information provided on Ped Onc Resource Center should not be used for diagnosing or treating a health problem or a disease. It is not a substitute for professional care. If you suspect your child has a health problem, you should consult your health care provider.

contact webmaster/ped-onc home/last updated 4/07