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Fighting Leukemia – Giving Hope
Blood is life. The truth of this statement becomes clear when a person's blood becomes diseased and his life is threatened. Leukemia is among the most insidious diseases; it is a malignant disorder of the white blood cells (leukocytes). It was first described in 1845 by the renowned physician Rudolf Virchow. He also gave it its name, originating from the Greek words for white (leukos) and blood (haema).
As with all cancers, leukemia starts to develop when a single cell changes into an abnormal cell. In leukemia it is an immature white blood cell that goes out of control.
Leukocytes are the cells that protect the body against infections. However, this function can only be fulfilled by fully developed blood cells since under normal circumstances only mature cells can reproduce. In leukemia certain genes in the body become altered and signal the immature blood cell to reproduce. These malignant blood cells are beyond the control of all the mechanisms that usually keep a very strict watch over the reproduction and maturation of defense cells. They reproduce uncontrollably even if there are no disease-causing pathogens in the body which need to be destroyed.
It is an irony of fate that people with leukemia develop infections far more often than usual in spite of the high level of leukocytes in their bodies. The reason for this is that the abnormal cancer cells are unable to deal with pathogens and foreign substances in the body because they have developed from immature blood cells. These immature leukocytes have not had time to learn how to function as defense cells. They patrol the blood in the form of a giant troop of useless, white leukemia cells, displacing the normal, functioning blood cells in the process. This is a life-threatening development for the body.
Chronic lymphocytic leukemia (CLL) is the most common form of leukemia in adults. It is particularly insidious because – unlike acute forms of leukemia - it can exist for a long time without causing symptoms, or it produces only vague symptoms such as tiredness, night sweats or swollen glands. This is why it is often not diagnosed until a very late stage. In Europe and the United States there are currently around 120,000 people with CLL, most of them over 50 years old. The cause of the disease is unknown. Exposure to radiation, chemicals and viruses and genetic factors are thought to be implicated.
CLL is characterized by the accumulation of functionally immature lymphocytes in the bone marrow, blood, lymphatic tissue and other organs. There are two types of the smallest white blood cells: B-cells and T-cells. In 95 percent of all cases of CLL it is the B-lymphocytes which are affected.
CLL is classified both as a leukemia and as a non-Hodgkin's lymphoma (NHL). NHLs are among the most common malignant diseases of the blood and lymphatic system. This class of malignancies includes numerous disease entities which develop from different cells within the body's defense system. All these cells may mutate and turn into cancer. They occur throughout the body, so NHL may originate in one of many places and spread through the lymphatic system.
There are around 230,000 cases of NHL in the European Union, with some 70,000 cases newly diagnosed each year. And the trend is an upward one. Most of the people affected are elderly. The first signs are enlarged, usually painless lymph nodes accompanied by vague symptoms. Patients feel tired, have no appetite and feel nauseous. And they are more prone than usual to infections.
Neither chronic lymphocytic leukemia nor non-Hodgkin's lymphoma can be cured at present. However, a number of therapies are available which improve patients' quality-of-life and help them to live longer.
Both classic chemotherapy and antibodies have proved successful in controlling CLL. Antibodies destroy sick cells and remove malignant lymphocytes from blood, bone marrow and other affected organs.
Antibodies are also at the heart of an innovative form of therapy developed by Bayer Schering Pharma: radioimmunotherapy. This combines the specificity of a monoclonal antibody with the cytotoxic effect of irradiation with yttrium-90 in the therapy of tumors.
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