Childhood Acute Lymphoblastic Leukemia Treatment (PDQ®)–Patient Version
General Information About Childhood Acute Lymphoblastic Leukemia
KEY POINTS
- Childhood acute lymphoblastic leukemia (ALL) is a type of cancer in which the bone marrow makes too many immature lymphocytes (a type of white blood cell).
- Leukemia may affect red blood cells, white blood cells, and platelets.
- Past treatment for cancer and certain genetic conditions affect the risk of having childhood ALL.
- Signs of childhood ALL include fever and bruising.
- Tests that examine the blood and bone marrow are used to detect (find) and diagnose childhood ALL.
- Certain factors affect prognosis (chance of recovery) and treatment options.
Childhood acute lymphoblastic leukemia (ALL) is a type of cancer in which the bone marrow makes too many immature lymphocytes (a type of white blood cell).
Childhood acute lymphoblastic leukemia (also called ALL or acute lymphocytic leukemia) is a cancer of the blood and bone marrow. This type of cancer usually gets worse quickly if it is not treated.
ALL is the most common type of cancer in children.
Leukemia may affect red blood cells, white blood cells, and platelets.
In a healthy child, the bone marrow makes blood stem cells (immature cells) that become mature blood cells over time. A blood stem cell may become a myeloid stem cell or a lymphoid stem cell.
A myeloid stem cell becomes one of three types of mature blood cells:
- Red blood cells that carry oxygen and other substances to all tissues of the body.
- Platelets that form blood clots to stop bleeding.
- White blood cells that fight infection and disease.
A lymphoid stem cell becomes a lymphoblast cell and then one of three types of lymphocytes (white blood cells):
- B lymphocytes that make antibodies to help fight infection.
- T lymphocytes that help B lymphocytes make the antibodies that help fight infection.
- Natural killer cells that attack cancer cells and viruses.
In a child with ALL, too many stem cells become lymphoblasts, B lymphocytes, or T lymphocytes. The cells do not work like normal lymphocytes and are not able to fight infection very well. These cells are cancer (leukemia) cells. Also, as the number of leukemia cells increases in the blood and bone marrow, there is less room for healthy white blood cells, red blood cells, and platelets. This may lead to infection, anemia, and easy bleeding.
This summary is about acute lymphoblastic leukemia in children, adolescents, and young adults. See the following PDQ summaries for information about other types of leukemia:
Past treatment for cancer and certain genetic conditions affect the risk of having childhood ALL.
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. Talk with your child's doctor if you think your child may be at risk.
Possible risk factors for ALL include the following:
- Being exposed to x-rays before birth.
- Being exposed to radiation.
- Past treatment with chemotherapy.
- Having certain genetic conditions, such as:
- Down syndrome.
- Neurofibromatosis type 1.
- Bloom syndrome.
- Fanconi anemia.
- Ataxia-telangiectasia.
- Li-Fraumeni syndrome.
- Constitutional mismatch repair deficiency (mutations in certain genes that stop DNA from repairing itself, which leads to the growth of cancers at an early age).
- Having certain changes in the chromosomes or genes.
Signs of childhood ALL include fever and bruising.
Tests that examine the blood and bone marrow are used to detect (find) and diagnose childhood ALL.
The following tests and procedures may be used to diagnose childhood ALL and find out if leukemia cells have spread to other parts of the body such as the brain or testicles:
- 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) with differential : A procedure in which a sample of blood is drawn and checked for the following:
- The number of red blood cells and platelets.
- The number and type of white blood cells.
- 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.
- 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.
- Bone marrow aspiration and biopsy : The removal of bone marrow and a small piece of bone by inserting a hollow needle into the hipbone or breastbone. A pathologistviews the bone marrow and bone under a microscope to look for signs of cancer.The following tests are done on blood or the bone marrow tissue that is removed:
- Cytogenetic analysis : A laboratory test in which the cells in a sample of blood or bone marrow are viewed under a microscope to look for certain changes in the chromosomes of lymphocytes. For example, in Philadelphia chromosome –positive ALL, part of one chromosome switches places with part of another chromosome. This is called the “Philadelphia chromosome.”
- Immunophenotyping : A laboratory test in which the antigens or markers on the surface of a blood or bone marrow cell are checked to see if they are lymphocytes or myeloid cells. If the cells are malignant lymphocytes (cancer) they are checked to see if they are B lymphocytes or T lymphocytes.
- Lumbar puncture : A procedure used to collect a sample of cerebrospinal fluid (CSF) from the spinal column. This is done by placing a needle between two bones in the spine and into the CSF around the spinal cord and removing a sample of the fluid. The sample of CSF is checked under a microscope for signs that leukemia cells have spread to the brain and spinal cord. This procedure is also called an LP or spinal tap.This procedure is done after leukemia is diagnosed to find out if leukemia cells have spread to the brain and spinal cord. Intrathecal chemotherapy is given after the sample of fluid is removed to treat any leukemia cells that may have spread to the brain and spinal cord.
- 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. The chest x-ray is done to see if leukemia cells have formed a mass in the middle of the chest.
Certain factors affect prognosis (chance of recovery) and treatment options.
- How quickly and how low the leukemia cell count drops after the first month of treatment.
- Age at the time of diagnosis, sex, race, and ethnic background.
- The number of white blood cells in the blood at the time of diagnosis.
- Whether the leukemia cells began from B lymphocytes or T lymphocytes.
- Whether there are certain changes in the chromosomes or genes of the lymphocytes with cancer.
- Whether the child has Down syndrome.
- Whether leukemia cells are found in the cerebrospinal fluid.
- The child's weight at the time of diagnosis and during treatment.
Treatment options depend on:
- Whether the leukemia cells began from B lymphocytes or T lymphocytes.
- Whether the child has standard-risk, high-risk, or very high–risk ALL.
- The age of the child at the time of diagnosis.
- Whether there are certain changes in the chromosomes of lymphocytes, such as the Philadelphia chromosome.
- Whether the child was treated with steroids before the start of induction therapy.
- How quickly and how low the leukemia cell count drops during treatment.
For leukemia that relapses (comes back) after treatment, the prognosis and treatment options depend partly on the following:
- How long it is between the time of diagnosis and when the leukemia comes back.
- Whether the leukemia comes back in the bone marrow or in other parts of the body.
No comments:
Post a Comment