Skip navigation | ||
|
||
Medical Encyclopedia |
|
Other encyclopedia topics: | A-Ag Ah-Ap Aq-Az B-Bk Bl-Bz C-Cg Ch-Co Cp-Cz D-Di Dj-Dz E-Ep Eq-Ez F G H-Hf Hg-Hz I-In Io-Iz J K L-Ln Lo-Lz M-Mf Mg-Mz N O P-Pl Pm-Pz Q R S-Sh Si-Sp Sq-Sz T-Tn To-Tz U V W X Y Z 0-9 |
Contents of this page: | |
|
|
|
|
|
Alternative names Return to top
ALL; Acute childhood leukemia; Cancer - acute childhood leukemia (ALL)Definition Return to top
Acute lymphocytic leukemia is a progressive, malignant disease characterized by large numbers of immature white blood cells that resemble lymphoblasts. These cells can be found in the blood, the bone marrow, the lymph nodes, the spleen, and other organs.Causes, incidence, and risk factors Return to top
Acute lymphocytic leukemia (ALL) is responsible for 80% of the acute leukemias of childhood, with the peak incidence occurring between ages 3 and 7. ALL also occurs in adults, where it comprises 20% of all adult leukemias.
In acute leukemia, the malignant cell loses its ability to mature and specialize (differentiate) its function. These cells multiply rapidly and replace the normal cells. Bone marrow failure occurs as malignant cells replace normal bone marrow elements. The person becomes susceptible to bleeding and infection because the normal blood cells are reduced in number.
Most cases seem to have no apparent cause. However, radiation, some toxins such as benzene, and some chemotherapy agents are thought to contribute to the induction of leukemia. Abnormalities in chromosomes may also play a role in the development of acute leukemia.
Risk factors for acute leukemia include Down syndrome, a sibling with leukemia, and exposure to radiation, chemicals, and drugs. The incidence is 6 out of 100,000 people.
Symptoms Return to top
Signs and tests Return to top
Physical examination shows enlarged liver and spleen, bruising (ecchymosis) and evidence of bleeding (petechiae, purpura, and so on).ALL may also alter the results of the following tests:
Classification of ALL now depends on a number of specific sophisticated tests, such as immunophenotyping, karyotyping, and terminal deoxynucleotidyltransferase (TdT) activity. The combined results of these tests allows pinpoint molecular diagnosis, which helps guide the treatment decisions, and clarify the likely prognosis.
For instance, the cells of some leukemias contain chromosomal abnormalities. Those with the Philadelphia chromosome or with the t(4;11) translocation would tend to have a poor prognosis, thus intensive treatment and an early bone marrow transplant might be recommended preemptively. Other genes (such as the TEL/AML1 rearrangement) can indicate a very favorable prognosis.
Treatment Return to top
The goal of treatment is remission of the cancer. A remission is achieved when the peripheral blood counts and the bone marrow are normal.Support Groups Return to top
The stress of illness can often be helped by joining a support group where members share common experiences and problems. See cancer - support group and leukemia - support group.Expectations (prognosis) Return to top
The probable outcome for children is better than for adults, with an 80% cure rate. Eighty percent of adults achieve complete remission, with 30% to 50% being cured. Without treatment, the life expectancy is about 3 months.Complications Return to top
Calling your health care provider Return to top
Call for an appointment with your health care provider if symptoms suggestive of ALL develop.Prevention Return to top
Because the cause of most cases is unknown, prevention of most cases is not possible. Minimizing exposure to toxins, radiation, chemicals, etc. may reduce risk. Update Date: 10/28/2003 Updated by: Ezra E. W. Cohen, M.D., Section of Hematology/Oncology, Department of Medicine, The University of Chicago, Chicago, IL. Review provided by VeriMed Healthcare Network.
Home | Health Topics | Drug Information | Encyclopedia | Dictionary | News | Directories | Other Resources | |
Copyright | Privacy | Accessibility | Selection Guidelines U.S. National Library of Medicine, 8600 Rockville Pike, Bethesda, MD 20894 National Institutes of Health | Department of Health & Human Services |
Page last updated: 28 October 2004 |