Should All Patients with Acute Myelogenous Leukemia (AML) Other Than Good Risk Cytogenetics Receive Allogeneic Hematopoietic Stem Cell Transplantation (HSCT) in First Remission?

There has been little improvement in the standard therapy of AML in the last two decades. Allogeneic HSCT remains the most effective curative therapy for patients with AML; however, risks associated with this therapy have limited its use for patients of advanced age or requiring alternate donors. Improvements in supportive care, donor selection and conditioning protocols have decreased the risk of transplant related mortality and allogeneic HSCT now appears as a feasible option for elderly patients. We reviewed the outcome of 99 patients with AML and MDS who received allogeneic HSCT in our center from 6/98 to 12/07. 85 patients were diagnosed with AML and 14 patients had MDS. 25 patients with AML (29%) had secondary AML including chemotherapy-related (6 patients) and progression from MDS or myeloproliferative disease (19 patients). Median age was 51 (20–72). Patients received allografts from related donors (n=56) and unrelated donors (URD) (n=43). All patients who received URD in first remission had poor prognostic features. 56 patients received myeloablative conditioning protocols (MA) whereas 43 patients were transplanted with reduced intensity protocols (RI) primarily due to age >55. Overall probabilities of 4-year and 8-year survival are 51% and 41% respectively. The median follow-up is 30 months for surviving patients. RI-group (Median age: 62 (37–72) had a similar 4-year survival with MA-group (50% and 54% respectively). 4-Year probability of survival in elderly patients (age>60) after RI-HSCT (n=27) is 48%. Patients who received an URD allograft and RI conditioning (n=21) had a similar survival to those receiving MA conditioning and URD graft (n=22) (4-year survival 52% and 54% respectively). As expected, AML patients in first complete remission (CR1) had better survival than patients who were in second or higher complete remission (CR2) (4-year survival; 53% vs 29%). We conclude that HSCT for AML and MDS from related or unrelated donors, with age and comorbidity-appropriate conditioning, results in a favorable outcome compared to historical experiences with standard therapy. Allogeneic HSCT should be tested in first remission for all patients with AML excluding younger patients with good risk features.