Transformation of chronic lymphocytic leukemia into acute mixed phenotype leukemia myeloid/T neoplasm: a rare case report

Abstract

Introduction: Chronic lymphocytic leukemia (CLL) is defined by the presence of lymphocyte in the blood, bone marrow, lymph nodes, and spleen, with a median lymphocyte count of 20–30×109/L for more than three months. CLL is known to be rarely associated with myeloid malignancies. This study presents an extremely rare case of CLL, which transformed into myeloid /T neoplasm.Case presentation: A 62-year-old man with a 10-year history of CLL was referred to our hospital because of multiple skin bruises and anemia. He was monitored for ten years without any treatment until this time when the disease progressed, and chemotherapy was started. After eight months of treatment completion, he deteriorated. This time, bone marrow biopsy immunophenotyping revealed the transformation of CLL into mixed phenotype acute leukemia, myeloid/T neoplasm with no residue of preexisting CLL.Conclusion: Transformation of CLL into acute leukemia may arise from the same clone. Still, there is some evidence that it may be therapy-related, so any deterioration in a patient with CLL should be evaluated promptly for a better outcome.