B-cell chronic lymphocytic leukemia is a low-grade, leukemic B-cell non-Hodgkin's lymphoma. It is the most common leukemic disease in Central Europe and is characterized by a clonal cell proliferation of immunocompetent (functionless) lymphocytes in the blood, bone marrow and lymphatic system.
The average age of onset is between 70 and 75 years. There are certain factors that may increase the risk of developing CLL including hereditary factors (people with caregivers also at increased risk) and organic solvents (benzene). The disease is very heterogeneous.
It is usually asymptomatic over a long period of time and is only diagnosed late or accidentally. Early symptoms may include decreased performance, B symptoms with fever, weight loss and night sweats and indolent lymph node swelling. As the disease progresses, hepatosplenomegaly, dermatological symptoms and immune deficiencies (antibody deficiency syndrome, granulocytopenia) develop. The latter are the most common cause of death.
To determine a patient's individual stage of disease, a staging is performed according to either the Binet or Rai classification criteria. Both systems take into account the lymphocyte count, the number of affected lymph node regions, hepato- or splenomegaly, and any anemia or thrombocytopenia.
An antineoplastic treatment is initiated only when symptoms appear. The prognosis of CLL is relatively good due to its occurrence in advanced age and the often slow course.