Occurrence of chronic lymphocytic leukemia in patients with chronic myelogenous leukemia.

Chronic lymphocytic leukemia (CLL) is the most common leukemia of adults in the western world and constitutes about 33% of all leukemia's. The incidence of CLL increases with age and are more common in older population. Chronic myeloid leukemia (CML) on the contrary occurs in both young adults and elderly and is a chronic myeloproliferative disease that originates from abnormal pluripotent stem cells and results in involvement of multiple hematopoietic lineages, but predominantly myeloid and less commonly lymphoid. Association between CLL and myeloid malignancies (CML, acute myeloid leukemia and MDS, myelodysplastic syndrome) is rare. In literature documenting CLL and CML in same patients, occur either simultaneously or CML is preceded by CLL.