RECURRENT ISOLATED EXTRAMEDULLARY RELAPSES AS GRANULOCYTIC SARCOMAS FOLLOWING ALLOGENEIC BONE-MARROW TRANSPLANTATION FOR ACUTE MYELOID-LEUKEMIA

Isolated extramedullary relapses as granulocytic sarcomas (GS) followi ng allogeneic bone marrow transplantation (BMT) for acute myeloid leuk emia (AML) are rare events. We describe three such patients who presen ted with a unique pattern of GS relapse post-BMT, The clinical feature s included repeated relapses in multiple sites, absence of marrow invo lvement, and prolonged survival, Fluorescence in situ hybridization (F ISH) demonstrated persistence of donor hematopoiesis despite dissemina ted GS, The findings indicated that a graft-versus-leukemia (GVL) effe ct might operate more strongly in the marrow than in peripheral sites, Finally, our observations suggest that isolated GS relapses after BMT might be compatible with long survivals, and that in patients with ma rrow hematopoiesis of donor origin, augmentation of the GVL effect mig ht be of use.