What is leukemia?
Leukemia is cancer of the blood cells. Blood cells are made by your bone marrow, which is the soft tissue in the middle of most bones.
Leukemia starts with chromosome changes in cells. These changes are called mutations, and mutations change the way cells work and grow.
With leukemia, the bone marrow starts making too many white blood cells, and sometimes these cells don't work right. These cells keep growing when they are supposed to stop. They also grow faster than your other cells. Over time, these abnormal cells crowd out your normal white blood cells, red blood cells, and platelets.
Your white blood cells help your body fight infection. Your red blood cells make sure all your body parts have the oxygen they need. Your platelets keep you from bleeding too much. When the leukemia cells crowd out your normal cells, your blood cannot do its job. You may bleed or bruise easily, get sick more often, and feel very tired.
Are there different types of leukemia?
There are four main types of leukemia. Acute leukemia gets worse very quickly. People with acute leukemia often feel sick right away. Chronic leukemia gets worse slowly, and you may not have any symptoms until later on in the illness. Those two kinds of leukemia are divided according to which kind of white blood cells are involved, lymphocytes or myelocytes.
Acute lymphoblastic leukemia (ALL). ALL is the most common leukemia in children. Adults also get it.
Acute myelogenous leukemia (AML). AML affects both children and adults.
Chronic lymphocytic leukemia (CLL). CLL is the most common leukemia in adults, especially older adults. Children almost never get it. It mostly affects people who are older than 55.
Chronic myelogenous leukemia (CML). CML occurs mostly in adults.
What causes leukemia?
The cause of leukemia is not known. But there are some things that can raise your risk of getting some kinds of leukemia. These risk factors include certain chemotherapy treatments, being exposed to large amounts of radiation or some chemicals in the workplace, and smoking and tobacco use.
Most types of leukemia do not seem to run in families, but in some cases, CLL does.1 There are also certain genetic conditions, like Down syndrome, that can make AML more likely.
Most people who get leukemia do not have any risk factors.
What are the symptoms?
Symptoms may include:
Fevers and night sweats.
Weakness and fatigue.
Bruising of the skin and bleeding from the gums or rectum.
Swelling in the belly or pain on the left side of the belly or in the left shoulder from a swollen spleen.
Swollen lymph nodes in the armpit, neck, or groin.
Decreased appetite and weight loss because you feel full and don't want to eat.
The chronic forms of leukemia often cause no symptoms at first.
How is leukemia diagnosed?
If your doctor thinks you might have leukemia, he or she will ask questions about your past and present symptoms, do a physical exam, and order blood tests.
If your blood tests are not normal, you may need a test of cells from inside your bone, called a bone marrow biopsy. Bone marrow cells give key information for diagnosing most kinds of leukemia.
How is it treated?
Treatment depends on what kind of leukemia you have and how far along it is. Treatment can range from watchful waiting to a stem cell transplant. Usually it includes chemotherapy and sometimes radiation treatments.