Leukemia

Leukemia at a Glance

• Leukemia is a form of cancer that begins in the blood-forming cells of the bone marrow—the soft, inner part of the bones.
• Leukemia, which literally means "white blood" in Greek, occurs when there is an excess of abnormal white blood cells in the blood.
• The many risk factors for leukemia include exposure to very high levels of radiation such as in radiation therapy or atomic bomb survivors, repeated diagnostic x-rays, smoking, exposure to benzene in the workplace, chemotherapy for cancer, Down syndrome, certain blood disorders, family history of leukemia, and Human T-cell leukemia virus type I.
• Symptoms include swollen lymph nodes especially lymph nodes in the neck or armpit, fevers or night sweats, frequent infections, feeling weak or tired, bleeding gums, purplish patches in the skin, tiny red spots under the skin, swelling or discomfort in the abdomen, weight loss for no known reason, pain in the bones or joints.
• Physicians have many well-studied and well-tested treatments in their arsenal to battle leukemia and survival rates have improved dramatically in the past decade.

In 2010 in the United States, 43,050 new cases are estimated to be diagnosed and 21,840 persons may die from leukemia.

Leukemia Cells

Most blood cells develop from cells in the bone marrow called stem cells. 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.

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 – Chronic leukemia usually gets worse slowly.
• Acute -- Chronic leukemia usually gets worse quickly.

The types of leukemia can also be grouped based on the type of white blood cell that is affected.

Leukemia can start in lymphoid cells or myeloid 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.