Chronic lymphocytic leukemia
Chronic lymphocytic leukemia (CLL) is a hematological malignancy characterized by the proliferation of mostly mature but abnormal leukocytes.
Epidemiology
Chronic lymphocytic leukemia is considered the most common type of leukemia in the Western hemisphere; its prevalence in Europe and North America ranges from 29-38% of all leukaemias . It primarily affects adults ~65-70 years of age .
Clinical presentation
Up to half of the patients can be asymptomatic with the disease being incidentally discovered by routine blood workup . Patients may sometimes present with hepatomegaly, splenomegaly or both and/or hemolytic anemia.
Pathology
It is a B-lineage neoplasm of prefollicular center cells that is usually associated with circulating neoplastic small lymphocytes. From a morphologic and immunophenotypic perspective, the malignant cells of chronic lymphocytic leukemia tend to be identical to those of nodal-based small lymphocytic lymphoma (SLL), and these two malignancies are thought to represent different manifestations of the same disease .
Staging
There are two common staging systems in use which are:
Diagnosis
The diagnosis is generally established by a bone marrow biopsy and immunophenotyping.
Radiographic features
Imaging may identify various features of the disease such as splenomegaly, hepatomegaly +/- lymphadenopathy, although these are not specific for the disease.
MRI
As with other types of bone marrow infiltrative disease, it is possible to see a diffusely hypointense signal of bone structures on T1, easier to see on spinal MRI.
Treatment and prognosis
Chronic lymphocytic leukemia treatment is offered in the presence of active disease, which is characterized by any of the listed below :
- presence of B symptoms
- progressive bone marrow failure
- extensive or rapidly progressing lymphadenopathy
- massive or rapidly progressive splenomegaly
- uncontrolled autoimmune cytopenias
- rapid lymphocyte doubling time: either occurring in less than 6 months or when there is an increase in 50% in ≤2 months
About one-third of patients with chronic lymphocytic leukemia will never require treatment .
Complications
Richter transformation: is defined as a diffuse large cell lymphoma, occurring by transformation of chronic lymphocytic leukemia .
See also
Siehe auch:
und weiter:
Assoziationen und Differentialdiagnosen zu Chronische lymphatische Leukämie: 
