Efficacy of myeloablative allogeneic hematopoietic stem cell transplantation in adult patients with MLL-ELL-positive acute myeloid leukemia

Int J Hematol. 2015 Jul;102(1):86-92. doi: 10.1007/s12185-015-1779-z. Epub 2015 Mar 11.

Abstract

Acute myeloid leukemia (AML) with mixed lineage leukemia-eleven-nineteen lysine-rich leukemia (MLL-ELL) is a rare subtype of MLL-rearranged AML. The outcome of allogeneic hematopoietic stem cell transplantation (allo-HSCT) for patients with this disease remains unknown. In the present study, we retrospectively investigated the efficacy of allo-HSCT in eight adult MLL-ELL-positive AML patients. Although all eight patients achieved first complete remission (CR1), three (37.5 %) patients experienced relapse after induction therapy. Five (62.5 %) patients underwent allo-HSCT during CR1, whereas two (25.0 %) underwent allo-HSCT during disease relapse, and one (12.5 %) during CR2. All three patients who received allo-HSCT beyond CR1 died due to AML progression after allo-HSCT. Of the five patients who received allo-HSCT during CR1, three (60.0 %) remained alive at study conclusion. The overall survival rate at five years was 50.0 %. Intriguingly, clonally expanded non-leukemic cells expressing MLL-ELL during consolidation therapy were found to be eradicated after allo-HSCT during the monitoring of minimal residual disease in one patient; this indicates that allo-HSCT is efficacious for eliminating pre-leukemic cells resistant to chemotherapy. In conclusion, allo-HSCT soon after CR1 represents a promising therapeutic option for adult AML patients with MLL-ELL, although the outcome of allo-HSCT for patients beyond CR1 was dismal.

MeSH terms

  • Adolescent
  • Adult
  • Chromosome Breakage
  • Disease Progression
  • Female
  • Graft vs Host Disease / etiology
  • Hematopoietic Stem Cell Transplantation* / adverse effects
  • Humans
  • Leukemia, Myeloid, Acute / diagnosis
  • Leukemia, Myeloid, Acute / genetics*
  • Leukemia, Myeloid, Acute / mortality
  • Leukemia, Myeloid, Acute / therapy*
  • Male
  • Myeloid-Lymphoid Leukemia Protein / genetics*
  • Neoplasm, Residual / diagnosis
  • Neoplasm, Residual / genetics
  • Oncogene Proteins, Fusion / genetics*
  • Reverse Transcriptase Polymerase Chain Reaction
  • Transplantation Conditioning*
  • Transplantation, Homologous
  • Treatment Outcome
  • Young Adult

Substances

  • MLL-ELL fusion protein, human
  • Oncogene Proteins, Fusion
  • Myeloid-Lymphoid Leukemia Protein