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Introduction
Leukemia is a cancer that starts in the organs that
make blood, namely the bone marrow and the lymph
system. Depending on their characteristics, leukemias
can be divided into two broad types. Acute leukemia
gets worse quickly, with fast multiplication of
abnormal, immature blood cells called blasts., while
the chronic leukemias progress more slowly. The vast
majority of the childhood leukemias are of the acute
form.
Causes
Acute leukemias are of two types: acute lymphocytic
leukemia and acute myelogenous leukemia. Different
types of white blood cells are involved in the two
leukemias. In acute lymphocytic leukemia (ALL), it is
the T or the B lymphocytes that become cancerous. The
B cell leukemias are more common than T cell
leukemias. Acute myelogenous leukemia, also known as
acute nonlymphocytic leukemia (ANLL), is a cancer of
the monocytes and/or granulocytes.
Leukemia strikes both sexes and all ages. The human
T-cell leukemia virus is believed to be the causative
agent for some kinds of leukemias. However, the cause
of most leukemias is not known. Exposure to
ionizing radiation and to certain organic chemicals,
such as benzene, is believed to increase the risk of
getting leukemia. Having a history of diseases that
damage the bone marrow, such as aplastic anemia, or a
history of cancers of the lymphatic system puts people
at a high risk for developing acute leukemias.
Symptoms
The symptoms of leukemia are generally vague and
non-specific. A patient may experience all or some of
the following symptoms:
- Weakness or chronic fatigue
- Fever of unknown origin
- Frequent bacterial or viral infections
- Headaches
- Skin rash
- Easy bruising
- Bleeding from gums or nose
- Blood in urine or stools
- Abdominal fullness
- Increased menstrual bleeding
- Thickened and swollen gums
- Bone pain
- Joint pain
- Weight loss
- Fatigue
- Enlarged lymph nodes
- Shortness of breath
TreatmentLeukemia is treated mainly with chemotherapy,
although radiotherapy and biological therapy can play
a role in certain scenarios.
Standard induction therapy for acute myeloid leukemia
includes two drugs: An anthracycline (such as
daunorubicin or idarubicin) in combination with the
nucleoside analogue, cytosine arabinoside. These drugs
are administered intravenously over seven days, in the
most common induction regimen. Supportive care
(including anti-nauseant medications) is required
during the initial hospital stay for induction
therapy, which often lasts up to one month.
The chemotherapy drugs will kill normal bone marrow
and leukemic cells equally, so the most significant
side effects besides nausea and vomiting are a
temporary reduction of normal white blood cells, red
blood cells, and platelets. The lack of white cells
results in lowered immunity and a high likelihood of
infections. A low platelet count may result in easy
bruisability and spontaneous bleeding, and is treated
with routine platelet transfusions. A decrease in the
red cell count, termed anemia, may result in fatigue,
shortness of breath, and lack of energy. Red cell
transfusions are therefore used routinely.
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