What is leukemia?

Leukemia is cancer of the blood or bone marrow. This malignant disease is characterized by an abnormal increase of blood cell, usually leukocytes. Leukemia is a broad term covering a spectrum of diseases.

The blood consists of many tiny cells, which are bound to the plasma. There are three different kinds of cells:

  • Red blood cells (Erythrozytes) give the blood its color and transport oxygen from the lungs through the body.
  • White blood cells (Leucozytes), are part of the innate immune system and help the body to fight infections.
  • platelets (Thrombocytes) are involved in blood coagulation.

The blood cells have a limited life span. They die after few days (platelets) or few months (red blood cells). Therefore these blood cells are constantly being reproduced in the bone marrow.

This reproduction process may be malfunctioning: Mostly immature cells form and are incapable of fulfilling their tasks. This is referred to as leukemia or blood cancer.

Transplanting new healthy cells
The malignant disease causes the defective development of blood cells in the hollow bones. In such severe diseases the transplantation of healthy stem cells of an unrelated donor is often the only chance of survival for the patient.
During the transplantation the patient receives new full functioning stem cells. The blood cells and the immune system of the recipient can develop out of these stem cells.