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.Known as leukocytes, these cells are so plentiful in some patients that the blood actually has a whitish tinge.

As leukemia progresses, the cancer interferes with the body’s production of other types of blood cells, including red blood cells and platelets. This results in anemia (low numbers of red cells) and bleeding problems, in addition to the increased risk of infection caused by white cell abnormalities.

All over the world in every year more than 100 000 people fall prey to leukemia, which is a malignant cancer, and about 10 000 to 20 000 patients of them are children.Leukemia starts and spreads in the blood and marrow.Leukemia can be acute and chronic, myelogenous and lymphocytic the last two indicate the cells types involved.

The cancer is called lymphocytic leukemia when in blood can be found a lot of lymphocytes.In the case of myelogenouse leukemia, granulocytes or monocytes are the white blood cells that are multiplying.Lymphocytic leukemia and myelogenouse leukemia can be acute and chronic.The difference among acute and chronic leukemia is the development of the cells and the progress rate.The acute leukemia progress quickly and contains immature and functionless cells in marrow and blood, but the chronic leukemia is very slow and the cells are often mature and functionally active.

Leukemia is any of the sharp or persistent neoplastic ailments of bone marrow wherein unrestrained propagation of leukocytes or white blood corpuscles occurs, generally in association with anemia that is damaged blood clotting, and magnification of the liver, lymph nodes, and spleen. Leukemia is observed in animals including as cats, cattle, guinea pigs, over and above in humans. There is no age difference in leukemia disease that is both children as well adults may suffer from this fatal disease. The central organ of infection in the body is the bone marrow and it spreads to rest of the body with the progress of the disease.

Leukemia in other words is a form of cancer where the white blood cells becomes abnormal or huge abnormal cells are being produced by the bone marrow leading to various symptoms ultimately death. Thus leukemia can be considered as a fatal cancerous disease specially those chronic ones. Understanding the characteristics of the normal leukocytes is of great importance to know leukemia. The leucocytes produced in the bone marrow fight against the diseases and infections.