Granulocytic Sarcoma in Erythroleukemia (M6).

Granulocytic Sarcomas are extramedullary tumors composed of immature myeloid cells, these tumors can be seen in myeloid malignancies such as chronic myelogenous leukemia, myelodysplastic syndrome and acute myelogenous leukemia. They can be seen at the time of diagnosis of the myeloid malignancy, prior to diagnosis, or after treatment as a first sign of relapse. We report here the case of a young woman who presented with a 6 month history of a slowly enlarging nasal mass. Biopsies of the lesion had been inconclusive until a CBC revealed abnormal blasts in the peripheral blood. Subsequently bone marrow biopsy revealed more than 59% erythroid precursors with a preponderance of immature erythroblasts and 33% myeloblast consistent with AML (M6). Reanalysis of the nasal biopsy demonstrated positive staining for CD68, Myeloperoxidase, Lysozyme, and CD117, but negative for CD34, suggestive of granulocytic sarcoma. The patient received induction chemotherapy with idarubicin and cytarabine and achieved bone marrow remission along with complete resolution of the nasal mass. To our knowledge this is the first report of a granulocytic sarcoma in association with AML M6.