There has recently been a paradigm shift in how oncologists think about refractory AML, disease in which there was no meaningful response and which is therefore resistant to standard chemotherapy. Refractory and relapsed disease occurs in many acute myelogenous leukemia patients. Salvage chemotherapy offers a 30–70% chance of a second complete remission. Unfortunately, this second remission is usually short lived and salvage chemotherapy is rarely curative. Allogeneic bone marrow transplant, either human leukocyte antigen (HLA)-sibling matched or matched unrelated donor, is the only treatment to offer long-term disease-free survival and possible cure. Allogeneic transplantation is standard of care after AML relapse. For primary refractory patients, re-induction is appropriate whenever possible.
It used to be thought that allogeneic transplantation in the refractory setting can salvage about a third of patients but most recur quickly after obtaining a transient remission. More recent studies are showing that modern treatment methods are resulting in much higher response and cure rates.
An allogeneic HSCT using a matched related donor (MRD) or matched unrelated donor (MUD) represents the only potentially curative option for these individuals. In several retrospective studies OS rates have ranged from 13% at 5 years to 30% at 3 years, although this procedure is accompanied by NRM rates of 25%–62% in this setting. NCCN does nto discuss the refractory subtype of AML but a recent Canadiain guideline says: “Allogeneic stem cell transplantation offers the best chance of survival for relapsed or refractory AML patients.”
Mato AR, Morgans A, Luger SM.
Novel strategies for relapsed and refractory acute myeloid leukemia. Curr Opin Hematol. 2008 Mar;15(2):108-14.
Estey EH. Treatment of acute myeloid leukemia. Haematologica. 2009 Jan;94(1):10-6.
Hamadani M, Awan FT, Copelan EA. Hematopoietic stem cell transplantation in adults with acute myeloid leukemia. Biol Blood Marrow Transplant. 2008 May;14(5):556-67.