Azacitidine in the treatment of extramedullary relapse of AML after allogeneic hematopoietic cell transplantation

Abstract

Extramedullary relapse of AML after allogeneic hematopoietic SCT (HSCT) is rare and less well-defined than systemic disease relapse. In a European Group for Blood and Marrow Transplantation (EBMT) study, the incidence of extramedullary relapse after HSCT was as low as 0.65% in AML.1 However, other studies have reported an incidence of up to 20% among long-term survivors.1, 2, 3, 4, 5, 6 There are no established guidelines for clinical decision making pertaining to the treatment of extramedullary relapse after HSCT.7 Common practice entails a combination of localized radiation, systemic chemotherapy, immunotherapy with donor lymphocyte infusions (DLI), and repeated transplantation if possible. We present in this report our experience in treating two patients with extramedullary non-hematological disease in the setting of relapsed AML previously treated with HSCT, DLI, chemotherapy and radiotherapy.