Leukemia symptomp

Leukemia is a malignancy (cancer) of blood cells. In leukemia, abnormal blood cells are produced in the bone marrow. Usually, leukemia involves the production of abnormal white blood cells -- the cells responsible for fighting infection. However, the abnormal cells in leukemia do not function in the same way as normal white blood cells. The leukemia cells continue to grow and divide, eventually crowding out the normal blood cells. The end result is that it becomes difficult for the body to fight infections, control bleeding, and transport oxygen. Over 50,000 cases of leukemia occur yearly in the U.S.

There are different types of leukemia, based upon how quickly the disease develops and the type of abnormal cells produced. Leukemia is called an acute leukemia if it develops rapidly. Large numbers of leukemia cells accumulate very quickly in the blood and bone marrow, leading to symptoms such as tiredness, easy bruising, and susceptibility to infections. Acute leukemia requires fast and aggressive treatment.

There are around 54,000 new cases of leukemia each year in the U.S. and about 24,000 deaths due to leukemia. Leukemia makes up about 3% of all new cancer cases.

Chronic leukemias develop slowly over time. These leukemias may not cause specific symptoms at the beginning of their course. If left untreated, the cells may eventually grow to high numbers, as in acute leukemias causing similar symptoms.

Leukemias are further classified as myeloid or lymphoid, depending upon the type of white blood cell that makes up the leukemia cells. A basic understanding of the normal development of blood cells is needed to understand the different types of leukemia. Normal blood cells develop fromstem cells that have the potential to become many cell types. Myeloid stem cells mature in the bone marrow and become immature white cells called myeloid blasts. These myeloid blasts further mature to become either red blood cells, platelets, or certain kinds of white blood cells.

Lymphoid stem cells mature in the bone marrow to become lymphoid blasts. The lymphoid blasts develop further into T or B lymphocytes, special types of white blood cells. Myeloid leukemias are made up of cells that arise from myeloid cells, while lymphoid leukemias arise from lymphoid cells. Knowing the type of cell involved in leukemia is important in choosing the appropriate treatment.

Leukemia