- Chronic Leukemias are characterized by indolent courses in which patients can remain asymptomatic or with mild symptomology for years. The primary distinguishing feature of chronic leukemias is that neoplastic cells are relatively mature, indicating that there is no blockage to differentiation. Given their mature phenotype, these leukemic cells are relatively slow growing, explaining the indolent, chronic nature of these diseases. This stands in contrast to acute leukemias in which neoplastic cells display an undifferentiated blastic morphology and aggressive growth.
- Two basic subtypes of chronic leukemia exist in which the neoplastic cells display a lymphocytic morphology (Chronic Lymphocytic Leukemia) (CLL) or a granulocytic morphology (Chronic Myeloid Leukemia) (CML).