Leukemia

Leukemia is a cancer of the blood cells. Blood is made of three types of cells:

• White blood cells that fight infection
• Red blood cells that carry oxygen from the lungs to the rest of the body
• Platelets that help the blood clot and stop bleeding

These cells are made in the bone marrow, a spongy area in the center of the bones.

Once these cells mature, they leave the marrow and start circulating through the bloodstream.

If you have leukemia, the blueprint or genetic material in your blood cells gets damaged. That makes your bone marrow produce too many of one kind of cell, usually white blood cells. These cells get stuck at an early stage of development called blasts. The blasts grow rapidly and crowd your bone marrow so it can’t produce normal blood cells.

Because leukemia is a disease of your blood and bone marrow, it can travel to other parts of your body, including your liver, spleen, lymph nodes, spleen and skin.

The American Cancer Society estimates that about 61,000 people in the US will be diagnosed with leukemia in a given year.

Leukemia Types

Leukemias are classified by how fast they progress and by the type of cell involved.

Speed

Types of Cells

Leukemia Classifications

Risk Factors

If you’re diagnosed with leukemia, it’s not your fault. Risk factors for leukemia are mostly out of your control. They include:

• Previous cancer treatment. People who’ve had both chemotherapy and radiation for another cancer have the highest risk of leukemia.
• Specific blood disorders. People with myelodysplastic syndromes have an increased risk of leukemia.
• Environmental causes. Exposure to high levels of radiation, to benzene, and to some chemicals used in the petroleum and rubber industries have been linked to leukemia.
• Age. Most people with leukemia are over 60. Although you can develop it at any time of life, most types are rarely diagnosed in people under 40. Children are most typically diagnosed with acute lymphocytic leukemia.
• Gender. Leukemia is more common in men than women.
• Smoking. Use of cigarettes is a known risk factor for acute myeloid leukemia.
• Family history. You are at higher risk of developing leukemia if other family members have had it.

Symptoms

People are often diagnosed with leukemia when their doctor finds abnormal blood counts during a routine physical exam. The symptoms depend on the type of blood cell that’s being affected.

• Low red blood cells lead to anemia: Headaches, lightheadedness, shortness of breath, pallor and fatigue.
• Low white blood cells cause an increased risk of infections that are recurrent and difficult to treat
• Low platelets cause bruising, frequent nosebleeds, and red spots (petichiae) on the skin.

Acute leukemias can affect your brain and spinal cord, so you might have headaches, blurred vision, double vision, vomiting, or confusion.

Common Symptoms

• Fevers and night sweats
• Infections
• Shortness of breath
• Easy bruising
• Bleeding
• Ongoing exhaustion or fatigue
• General weakness
• Weight loss
• Joint pain
• Swollen or tender lymph nodes
• Increased size of the liver or spleen
• Swollen or bleeding gums

Diagnosis

Many people are diagnosed with leukemia during a doctor’s exam, when they find that their spleen, liver, or lymph nodes are enlarged. To determine if you have leukemia, you may have these tests:

• A complete blood count (CBC) gives your doctor a profile of your blood. It shows whether your bone marrow is making fewer white cells, red cells, platelets, or all three. If you’re anemic, additional tests can help determine if it’s caused by leukemia or iron, vitamin B12, or folate deficiencies.
• Bone marrow aspiration or biopsy uses a needle to sample marrow fluid (aspiration) or solid bone marrow tissue (core biopsy). This sampling usually happens at the back of your hip after numbing the area. A pathologist will then examine the cells under a microscope for abnormalities and to rule out other types of cancer.
• Spinal tap, also called a lumbar puncture, draws a small amount of cerebrospinal fluid from your spine. A pathologist will examine the fluid under a microscope to look for infection, cancer cells, or other problems.
• AML typing tests determine the extent of your cancer and classify it into a more specific AML type.
• Other tests, including cytogenetic studies, which look for chromosomal changes in your cells, immunohistochemistry studies that use antibodies to distinguish types of cancer cells, flow cytometry that uses a laser beam to look at proteins on cells’ surface, and molecular genetic studies that determine cancer cells’ specific traits.