Information on Leukemia

Leukemia or leukaemia is a cancer of the blood or bone marrow and is characterized by an abnormal proliferation of blood cells, usually white blood cells (leukocytes). It is part of the broad group of diseases called hematological neoplasms.

The types of leukemia are grouped by how quickly the disease develops and gets worse. Leukemia is either chronic (gets worse slowly) or acute (gets worse quickly):

Chronic leukemia — Early in the disease, the abnormal blood cells can still do their work, and people with chronic leukemia may not have any symptoms. Slowly, chronic leukemia gets worse. It causes symptoms as the number of leukemia cells in the blood rises.

Acute leukemia — The blood cells are very abnormal. They cannot carry out their normal work. The number of abnormal cells increases rapidly. Acute leukemia worsens quickly.

The types of leukemia are also grouped by the type of white blood cell that is affected. Leukemia can arise in lymphoid cells or myeloid cells. Leukemia that affects lymphoid cells is called lymphocytic leukemia. Leukemia that affects myeloid cells is called myeloid leukemia or myelogenous leukemia.