Secondary T-acute lymphoblastic leukaemia mimicking blast crisis in chronic myeloid leukaemia
A 34-year-old man with chronic myeloid leukaemia (CML) firstly developed a lymphoid blast crisis of B-cell type. After a second chronic phase which lasted for >4 years with maintenance chemotherapy of hydroxyurea, 6-mercaptopurine and methotrexate, he developed a T-cell acute lymphoblastic leukaemia of TcR-gamma delta+ type. Cytogenetic analysis revealed disappearance of the t(9:22) translocation and appearance of new abnormalities consistent with the diagnosis secondary acute leukaemia. To our knowledge, secondary leukaemia in CML has not previously been reported.