Idiopathic refractory sideroachrestic anemia (IRSA) progressing to acute mixed lymphoblastic-myelomonoblastic leukemia. Case report and review of the literature.

A longitudinal observation of a patient with idiopathic refractory sideroachrestic anemia (IRSA) progressing to acute mixed lymphoblastic-myelomonoblastic leukemia is reported. The leukemia was characterized by morphology, immunological cell markers, and dissociated clinical responsiveness to vincristine/prednisone and arabinosylcytosine/6-thioguanine. Attention is paid to the hematological changes prior to leukemia development. Acute leukemia was best heralded in this patient by a severe deterioration of dyserythropoiesis and by an increase of blasts in the marrow to more than 5%. The observed preleukemic features are compared to those described in the literature.