Chronic lymphocytic leukemia (synonyms: Blast relapse of lymphocytic leukemia; CLL [chronic lymphocytic leukemia]; CLL [chronic lymphocytic leukemia] in complete remission; Chronic lymphocytic leukemia; Chronic lymphocytic leukemia in complete remission; Chronic lymphoid leukemia; Chronic lymphocytic leukemia; Chronic lymphocytic leukemia in complete remission; Lymphadenosis; Lymphadenosis in complete remission; Richter syndrome; ICD-10-GM C91. 1-: B-cell chronic lymphocytic leukemia [CLL]) is a malignant neoplasm of the hematopoietic system (hemoblastosis).Chronic lymphocytic leukemia (CLL) is classified as a non-Hodgkin’s lymphoma. It is due to malignant transformation of a B-cell clone in 95% of cases and is considered a leukemic B-cell lymphoma.
Two subtypes are distinguished in CLL:
- More mature and genetically stable form with better prognosis.
- more immature and genetically unstable form with worse prognosis
CLL is the most common form of leukemia and occurs mainly in older age. It is one of the benign (benign) forms of leukemia.
Special forms of chronic lymphocytic leukemia see below classification.
Sex ratio: males to females is 2: 1.
Peak incidence: The maximum incidence of CLL is between the ages of 60 and 70. The median age at diagnosis is 70 years for men and 72 years for women.
The prevalence (disease incidence) is higher for Caucasians (light-skinned people) than for blacks. In Japan, CLL is very rare.
The incidence (frequency of new cases) is about 5 cases per 100,000 population per year (in Germany). The incidence is about 5 diseases in the 5th decade of life and about 30 diseases per 100,000 population per year in the 8th decade of life.
Course and prognosis: In CLL, the B cells (B lymphocytes; important for the formation of antibodies) are almost completely defective, so that bacterial infections occur frequently. The risk of thrombosis (blood clots) also increases because the number of platelets (blood clots) increases at the beginning of CLL. As the disease progresses, however, their number decreases, so bleeding can occur. Chronic leukemia develops insidiously and slowly. However, chronic lymphocytic leukemia typically has a variable course. In most patients, the disease is indolent (painless). Symptoms such as splenomegaly (enlargement of the spleen) and lymph node hyperplasia (enlargement of the lymph nodes) appear late or not at all. Life expectancy is hardly reduced in this case. In the more aggressive form of progression (about one in 5 is affected), a rapid disease dynamic develops, which leads to a shortened life expectancy. A permanent cure is only very rarely possible. Once therapy is completed, long-term follow-up is a priority in order to detect a recurrence (recurrence of the disease) at an early stage. Recurrences usually occur within the first one to two years after the end of therapy. Approximately 50% of patients die from infections.
The 5-year survival rate is approximately 50%.
