Abstract
A 67 year old male developed a therapy related myelodysplastic process culminating in acute myeloid leukemia 16 years following initial treatment for a large cell lymphoma. A second relapse of this leukemia showed 12% blasts including numerous giant blasts. The presence of giant blasts suggested the possibility of relapsed malignant lymphoma, however, flow cytometry and immunohistochemistry identified them as myeloid and chromosomal analysis revealed a near-tetraploid cell line. No evidence of lymphoma was seen. Although remission was induced with chemotherapy he subsequently relapsed with marrow and/or CNS involvement and was maintained on palliative therapy until he developed sepsis and died, 13 months following the observation of tetraploidy and 33 months following the onset of acute leukemia.