Leukemia is a group of cancers originating in the stem cells that create blood. It is a progressive disease that causes the bone marrow and other blood-forming organs to produce an abundance of abnormal blood cells: either lymphoid stem cells that go on to become white blood cells or myeloid stem cells that go on to become red blood cells, platelets, granulocytes, and monocytes.
Definition & Facts
Leukemia is cancer found in the blood cells. The bone marrow is the biggest producer of blood cells. The human body produces hundreds of billions of new blood cells every day in the marrow. The cancerous blood cells caused by leukemia overpower healthy blood cells, do not fight off infection, and interfere with vital organ processes including the production of new healthy blood cells. This causes problems such as anemia, increased number of infections, and problems with blood clotting. If left untreated, leukemia can be lethal.
There are many types of leukemia, but there are four that are most commonly diagnosed. They are first classified as acute or chronic and then later classified again as myeloid or lymphoid. These are the four main types:
- Acute myelogenous leukemia, or AML, is the most common type of leukemia in adults, but it can occur in children as well.
- Chronic myelogenous leukemia, or CML, is common in adults and young adults, but rare in children. Someone with CML may have few or no symptoms for long periods of time, months or years, before the leukemia cells grow more quickly and symptoms begin to show.
- Acute lymphocytic leukemia, or ALL, is the most common in children.
- Chronic lymphocytic leukemia, or CLL, is one of the most common in adults and young adults, but rare in children. The patient may feel well for years before they begin to see symptoms.
Symptoms & Complaints
Anemia makes people appear pale, feel exhausted, weak, and tired, yet their heart rate is high. Leukemia also slows the production of platelets. Lack of platelets causes one to bruise easily and bleed easily.
Additional symptoms of leukemia can include:
- Fevers with chills and night sweats
- Loss of appetite
- Weight loss
- Swollen lymph nodes, swollen liver, or enlarged spleen – causing a swollen abdomen
- Bone pain and joint pain
- Sore gums and bleeding gums
- Chest pain, coughing, shortness of breath
- Bruising and red spots beneath the skin
The exact cause of leukemia is not known. There are many possibilities for the onset of leukemia. Here are some facts that doctors do know:
- Chromosome abnormalities are associated with leukemia, but do not cause it.
- In some cases the cause is thought to be a combination of genetic factors combined with environmental factors.
- Mutation in the DNA leads to the onset of leukemia.
- Most cases are not believed to be hereditary, but certain genetic conditions can make a person more prone to mutations. These genetic conditions can be passed to offspring.
- Radiation exposure increases the likelihood of developing ALL, AML and CML.
- Exposure to chemicals such as benzene can increase the risk of developing leukemia.
Diagnosis & Tests
Sometimes leukemia may be unexpectedly diagnosed during a routine physical examination or during a routine blood test. At some point, the symptoms of leukemia will appear, and it is imperative that a person see their doctor if they experience the above mentioned symptoms. A doctor will perform a physical exam looking for signs of leukemia such as pale skin, swelling of the lymph nodes, and enlargement of the spleen and liver.
The doctor may also conduct a complete blood count that will show if the patient has an abnormal blood cell count which could support the diagnosis. Imaging tests such as CT scans, MRIs, and PET scans, and ultrasound can show swelling and see if metastasis has occurred. Most leukemias do not produce tumors.
In order to confirm the diagnosis and reveal what type of leukemia the patient has, a needle biopsy will be conducted. A sample of bone marrow is taken from the hip bone using a long, thin needle. The biopsy sample is sent to a laboratory for testing. The results of this biopsy are used to determine what stage of leukemia the patient has and the treatment that will be used.
Treatment & Therapy
There are many factors that will determine what type of treatment a doctor will provide including type of leukemia, age of the patient, overall health of the patient, and whether or not the leukemia is spreading to other parts of the body. Here are the common treatments:
- Chemotherapy is the most common form of treatment; it kills the leukemia cells.
- Biological therapy is used to teach the body’s immune system to recognize and kill leukemia cells.
- Radiation therapy uses either full-body or spot treatment radiation to damage the leukemia cells and hinder their growth.
- Stem cell transplants are also used to remove cancerous bone marrow and replace it with new bone marrow that is obtained from a donor.
- Targeted therapy uses drugs to attack weaknesses in the leukemia cells to help control them.
Prevention & Prophylaxis