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What Is Leukemia...
Leukemia is a cancer that occurs in blood cells. There are several types of leukemia and these are classified by how quickly they progress and which cells they affect. Leukemia in children, as in adults, is described in two ways. The types include:
acute (rapidly growing)
or
chronic (slowly growing).
Almost all childhood leukemia is acute.
The two main types of acute leukemia are:
Acute lymphocytic leukemia (ALL), also called acute lymphoblastic
leukemia. This leukemia starts from the lymphoid cells in the
bone marrow.
Acute myeloid leukemia (AML), also called acute myelogenous
leukemia, acute myelocytic leukemia, or acute non-lymphocytic
leukemia [ANLL]). This leukemia starts from the cells that form
red cells, white cells, and platelets.
Chronic leukemias may also be divided into two types -
chronic lymphocytic leukemia (CLL) and
chronic myelogenous leukemia (CML).
These forms of leukemia are very rare in children but chronic myeloid leukemia
(See Myeloid leukemia above for the different names it goes under) does occur
in children. It is treated the same as in adult.
Acute lymphocytic leukemia (ALL) is a cancer of the lymphocyte-forming cells
called lymphoblasts. In the past, ALL was divided into 3 major categories (L1,
L2, or L3) based on its morphology (appearance under the microscope).
L1 is the most common type in children.
Acute myelogenous leukemia (AML) is a cancer of one of the following types of
early (immature) bone marrow cells:
- myeloblasts - these cells normally 'form' granulocytes
- monoblasts - these cells normally 'become' monocytes
- erythroblasts - these cells 'mature' into red blood cells
- megakaryoblasts - these cells normally 'become' megakaryocytes, the cells that make platelets
In the case of leukemia, one blood cell goes awry and the body produces
large numbers of this cell. In most cases the cell that goes awry is the
white blood cell. When looked at under a microscope, these abnormally produced
cells look different then the healthy cells and do not function properly.
The body continues to produce these abnormal, non-functional cells, leaving
little space for healthy cells. This imbalance of healthy and unhealthy cells
is what causes the symptoms of leukemia.
The most common type is acute lymphoblastic leukaemia (ALL).
A recent study in the American Journal of Public Health reported an association
between household chemicals and ALL. In the study, the researchers from the
National Cancer Institute (NCI) and the University of Minnesota found children
were more likely to develop ALL if they lived in households where family
hobbies involved the use of solvents (such as refinishing furniture, or building
models). They were also more likely to develop ALL if more than 4 rooms in
the house had been painted while their mothers were pregnant.
According to the Children's Cancer Group Epidemiology Program, a network
of pediatric epidemiologists, children are 5 to 6 times more likely to develop
leukemia and brain cancer if their families use pesticides at home.
Leukemia, which is the most common childhood cancer, increased by more than
15% over the past 20 years. Most of the increase in leukemia rates in the
past 20 years has been in a kind of cancer called acute lymphoblastic leukemia
or ALL.
NOTE: This web site is designed for educational purposes only and is not engaged in rendering medical advice. The information provided through this site should not be used for diagnosing or treating a health problem or a disease. If you have or suspect you may have a health problem, you should consult your health care provider