Leukemia

Overview of Leukemia
Leukemia is a type of cancer that begins in blood cells. The blood cells are formed in the soft material in the centre of most bones called bone marrow. The bone marrow makes different types of blood cells. Each type has a special function:
White blood cells help fight infection.
Red blood cells carry oxygen to tissues throughout the body.
Platelets help form blood clots that control bleeding.
When the bone marrow produces abnormal white blood cells, this condition is termed as Leukemia and the abnormal cells are leukemia cells. At first, leukemia cells function almost normally. Over a period of time they may number out normal white blood cells, red blood cells and platelets and makes it hard for blood to do its work.

Causes of leukemia
Just like most of the cancers the exact causes of leukemia is unknown. However, research has shown that certain risk factors are more likely to develop leukemia. Following are the risk factors for leukemia:
Very high levels of radiation — People exposed to very high levels of radiation are much more likely than others to develop leukemia. Medical treatment that uses radiation can be another source of high-level exposure and result in leukemia.

Working with certain chemicals — Exposure to high levels of benzene anf formaldehyde chemical in the workplace can cause leukemia.

Chemotherapy – Cancer patients treated with certain cancer-fighting drugs sometimes later develop leukemia. For example, drugs known as alkylating agents are associated with the development of leukemia many years later.
Genetic faacors – Down syndrome and certain other genetic diseases such as those caused by abnormal chromosomes may increase the risk of leukemia.
Viral infection – Human T-cell leukemia virus-I (HTLV-I) causes a rare type of chronic lymphocytic leukemia known as human T-cell leukemia.

Myelodysplastic syndrome – People with this blood disease are at increased risk of developing acute myeloid leukemia.

Electromagnetic fields – Some studies suggest there is a very rare chance of getting leukemia due to exposure to electromagnetic fields.

All these above risk factors may cause leukemia. On the other hand, many who do get the disease may have none of these risk factors.



Symptoms of leukemia
Since leukemia cells are abnormal blood cells, therefore leukemia cells travel through the body via bloodstream. Depending on the abnormal cell count and where these cells collect, a leukemia patient may have a number of symptoms.
Common symptoms of leukemia:
Fevers or night sweats
Frequent infections
Feeling weak or tired
Headache
Bleeding and bruising easily (bleeding gums, purplish patches in the skin, or tiny red spots under the skin)
Pain in the bones or joints
Swelling or discomfort in the abdomen (from an enlarged spleen)
Swollen lymph nodes, especially in the neck or armpit
Weight loss
However such symptoms also occur due to some common infections or ailments and hence such symptoms are not sure signs of leukemia. In the early stages of chronic leukemia, the leukemia cells function almost normally. Symptoms may take a long period of time to appear. In acute leukemia, symptoms appear and get worse quickly. Symptoms of acute leukemia are vomiting, confusion, loss of muscle control, and seizures. Leukemia cells also can collect in the following body parts:
In testicles and cause swelling.
In the eyes or on the skin causes sores.
It can also affect the digestive tract, kidneys, lungs, or other parts of the body.

Diagnosis of leukemia
The exams and tests to diagnose leukemia may include the following:
Physical exam — This test includes checking for swollen lymph nodes, spleen, and liver.
Blood tests — Blood tests may reveal the number of blood cells and their percentage ratio. Leukemia increases white blood cells and decreases platelets and hemoglobin. The lab-tests check the blood whether leukemia has affected the liver and kidneys.
Biopsy — The doctor removes some bone marrow from the hipbone or another large bone for examination under a microscope. There are two ways the doctor can obtain bone marrow. Some patients will have both procedures:
Bone marrow aspiration: The doctor uses a needle to remove samples of bone marrow. Similar to what’s done in biopsy.
Cytogenetics — The lab looks at the chromosomes of cells from samples of peripheral blood, bone marrow, or lymph nodes.
Spinal tap — In this test the physician takes a sample of the cerebrospinal fluid (the fluid that fills the spaces in and around the brain and spinal cord). The procedure takes about 30 minutes and is performed with local anesthesia. The patient must lie flat for several hours afterward to keep from getting a headache. The labs then check the fluid for leukemia cells or other signs of problems that may cause to any of the symptoms mentioned above.
Chest x-ray — The x-ray can reveal signs of disease in the chest.


Treatment of leukemia
Depending on the type and extent of the disease, patients may undergo one or combination of the following treatments:
Chemotherapy
Biological therapy
Radiation therapy
Bone marrow transplantation
Surgery to remove enlarged spleen
Stem cell transplant


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