When should patients receive consolidation chemotherapy before allogeneic hematopoietic cell transplantation for acute myeloid leukemia in first complete remission?

Abstract

Allogeneic hematopoietic cell transplantation (alloHCT) is a potentially curative therapy for patients with acute myeloid leukemia. Despite the associated graft-versus-leukemia effect, leukemia relapse remains the most common cause of treatment failure after alloHCT. Here, we review the available data on whether there is an advantage in providing pretransplant consolidation chemotherapy prior to alloHCT. Randomized controlled studies are lacking. Data derive largely from four large retrospective registry studies. These analyses are consistent in demonstrating the lack of any survival benefit for pretransplant consolidation chemotherapy once a patient achieves a complete remission and a donor is readily available. These results are valid across conditioning regimen intensities, donor sources, and doses of cytarabine administered during consolidation. Available evidence suggests that patients with acute myeloid leukemia in first complete remission for whom a suitable donor is readily available should not be given pretransplant consolidation before proceeding to alloHCT, regardless of conditioning regimen intensity and that transplantation should be offered promptly at the time remission is achieved without undue delay. Nevertheless, patients for whom a suitable donor is not readily available after achieving first remission, should probably receive 'bridging' consolidation chemotherapy while waiting for a donor to be identified in an attempt to decrease the risk of early disease recurrence before transplantation. The role of minimal residual disease and genetic markers in directing consolidation choices are unclear to date.