Simultaneous existence of acute myeloid leukemia and chronic lymphocytic leukemia: a case report

BACKGROUND: The simultaneous Occurrence of chronic lymphocytic leukemia (CLL) and acute myeloid leukemia (AML) has been rarely reported. Most of these cases have been occurring more frequently as a secondary event in patients receiving chemotherapeutic agents for CLL. CASE PRESENTATION: We describe a case of a 77-year-old man who presented with fatigue, pallor and lower limb pain and weakness. Initial laboratory studies showed Hb 7.7 g/dl, WBC 279.6 × 10(9)/1, PLT 143× 10(9)/1. The peripheral blood (PB) smear examination showed circulating blast cells (20 %) cells and 50 % lymphocytes, with smudge cells. A bone marrow examination showed infiltration by two discrete abnormal cell populations, one represents the leukemic blast cells (60 %) and the other represents small mature lymphocytes (30 %). The immunologic phenotype of blasts was characterized by the co-expression of CD13, CD33, CD14, CD4, CD15, CD64, HLA-DR, CD11c. Lymphocytes were characterized by a typical CLL immunophenotype: CD19+, CD5+, CD23+, CD20+ (dim) and negative for FMC7, CD34, CD10 and TdT. Cytogenetic studies were negative for CLL and AML panels. PCR assays for AML specific genetic abnormalities were negative. Immunoglobulin gene analysis established the clonal nature of the B-cell expansion. A final diagnosis of concomitant CLL and AML(FAB: M5) was made. CONCLUSION: We have reported a case in which there was simultaneous presentation of AML and CLL. Both forms of leukemia were well documented by morphology, cytometric analysis and molecular studies. Our findings support the idea that this rare concurrence of AML and untreated CLL may represent two separate disease processes.