Researcher - Leukemia

I chose to research leukemia because Holdens younger brother Allie was diagnosed with cancer.

Leukemia is cancer that starts in the tissue that forms blood. To understand cancer, it helps to know how normal blood cells form.

Normal Blood Cells

Most blood cells develop from cells in the bone marrow called stem cells. Bone marrow is the soft material in the center of most bones.

Stem cells mature into different kinds of blood cells. Each kind has a special job:

White blood cells help fight infection. There are several types of white blood cells.

Red blood cells carry oxygen to tissues throughout the body.

Platelets help form blood clots that control bleeding.

White blood cells, red blood cells, and platelets are made from stem cells as the body needs them. When cells grow old or get damaged, they die, and new cells take their place.

The picture below shows how stem cells can mature into different types of white blood cells. First, a stem cell matures into either a myeloid stem cell or a lymphoid stem cell:

• A myeloid stem cell matures into a myeloid blast. The blast can form a red blood cell, platelets, or one of several types of white blood cells.



• A lymphoid stem cell matures into a lymphoid blast. The blast can form one of several types of white blood cells, such as B cells or T cells.

The white blood cells that form from myeloid blasts are different from the white blood cells that form from lymphoid blasts.

In a person with leukemia, the bone marrow makes abnormal white blood cells. The abnormal cells are leukemia cells.

Unlike normal blood cells, leukemia cells don't die when they should. They may crowd out normal white blood cells, red blood cells, and platelets. This makes it hard for normal blood cells to do their work.

Types of Leukemia

The types of leukemia can be grouped based on how quickly the disease develops and gets worse. Leukemia is either chronic (which usually gets worse slowly) or acute (which usually gets worse quickly):

• Chronic leukemia: Early in the disease, the leukemia cells can still do some of the work of normal white blood cells. People may not have any symptoms at first. Doctors often find chronic leukemia during a routine checkup - before there are any symptoms.

  Slowly, chronic leukemia gets worse. As the number of leukemia cells in the blood increases, people get symptoms, such as swollen lymph nodes or infections. When symptoms do appear, they are usually mild at first and get worse gradually.




• Acute leukemia: The leukemia cells can't do any of the work of normal white blood cells. The number of leukemia cells increases rapidly. Acute leukemia usually worsens quickly.

The types of leukemia also can be grouped based on the type of white blood cell that is affected. Leukemia can start in lymphoid cells or myeloid cells. See the picture of these cells. Leukemia that affects lymphoid cells is called lymphoid, lymphocytic, or lymphoblastic leukemia. Leukemia that affects myeloid cells is called myeloid, myelogenous, or myeloblastic leukemia.

There are four common types of leukemia:

• Chronic lymphocytic leukemia (CLL): CLL affects lymphoid cells and usually grows slowly. It accounts for more than 15,000 new cases of leukemia each year. Most often, people diagnosed with the disease are over age 55. It almost never affects children.

• Chronic myeloid leukemia (CML): CML affects myeloid cells and usually grows slowly at first. It accounts for nearly 5,000 new cases of leukemia each year. It mainly affects adults.

• Acute lymphocytic (lymphoblastic) leukemia (ALL): ALL affects lymphoid cells and grows quickly. It accounts for more than 5,000 new cases of leukemia each year. ALL is the most common type of leukemia in young children. It also affects adults.

• Acute myeloid leukemia (AML): AML affects myeloid cells and grows quickly. It accounts for more than 13,000 new cases of leukemia each year. It occurs in both adults and children.

The risk factors may be different for the different types of leukemia:

• Radiation: People exposed to very high levels of radiation are much more likely than others to get acute myeloid leukemia, chronic myeloid leukemia, or acute lymphocytic leukemia.
• Radiation therapy: Another source of exposure to high levels of radiation is medical treatment for cancer and other conditions. Radiation therapy can increase the risk of leukemia.
• Chemotherapy: Cancer patients treated with certain types of cancer-fighting drugs sometimes later get acute myeloid leukemia or acute lymphocytic leukemia. For example, being treated with drugs known as alkylating agents or topoisomerase inhibitors is linked with a small chance of later developing acute leukemia.

Symptoms

Like all blood cells, leukemia cells travel through the body. The symptoms of leukemia depend on the number of leukemia cells and where these cells collect in the body.

People with chronic leukemia may not have symptoms. The doctor may find the disease during a routine blood test.

People with acute leukemia usually go to their doctor because they feel sick. If the brain is affected, they may have headaches, vomiting, confusion, loss of muscle control, or seizures. Leukemia also can affect other parts of the body such as the digestive tract, kidneys, lungs, heart, or testes.

Common symptoms of chronic or acute leukemia may include:

• Swollen lymph nodes that usually don't hurt (especially lymph nodes in the neck or armpit)



• fevers or night sweats



• Frequent infections



• Feeling weak or tired



• Bleeding and bruising easily (bleeding gums, purplish patches in the skin, or tiny red spots under the skin)


• Swelling or discomfort in the abdomen (from a swollen spleen or liver)



• weight loss for no known reason



• Pain in the bones or joints