General AML

The prognostic value of absolute monocyte count post-transplant in AML patients

Recent studies have reported that absolute monocyte count (AMC) at diagnosis has prognostic value in hematological malignancies, such as lymphomas, leukemias, and multiple myeloma.1,2,3 Liyuan Tang from The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, China, and colleagues published results in Leukemia Research of their retrospective study assessing the prognostic value of AMC in patients with acute myeloid leukemia (AML) who previously received myeloablative conditioning (MAC) allogeneic hematopoietic stem cell transplant (allo-HSCT) with busulfan and cyclophosphamide (Bu/Cy).4

In total, 59 consecutive AML patients (median age = 37 years, range 6–64) in remission who underwent HSCT using HLA-matched related (MRD), unrelated (MUD), or haploidentical related (HID) donors between January 2010 and December 2016 were analyzed in this study. AMC was collected on Days 15, 30, 60 and 100 post-HSCT. Data were collected from the electronic patient records of the First Affiliated Hospital of Wenzhou Medical University, China.

Using ROC analysis, the researchers identified the optimal cut-off value for AMC at 0.57×109/L.

Key findings:
  • Overall survival (OS) for patients with high AMC (≥ 0.57 × 109/L) was significantly inferior than in patients with low AMC (< 0.57 × 109/L) on Day 15 after transplant, P = 0.0049
  • High AMC on Day 15 after transplant is a poor prognostic factor for OS(P = 0.008) and post-relapse survival (PRS, P = 0.030)
  • No significant differences were found in relapse incidence (P = 0.437) or non-relapse mortality (P = 0.078)

In summary, Tang and colleagues concluded that patients with AMC ≥ 0.57 × 109/L on Day 15 after transplantation had inferior OS and PRS. The limitations of this study included its retrospective nature and the small number of patients. The authors further added that their analysis “needs to be validated in a larger prospective study with an independent cohort”.

References
  1. Herishanu Y. et al. Absolute monocyte count trichotomizes chronic lymphocytic leukemia into high risk patients with immune dysregulation, disease progression and poor survival. Leuk. Res. 2013. DOI: 10.1016/j.leukres.2013.07.017.
  2. Tadmor T. et al. Absolute monocytosis at diagnosis correlates with survival in diffuse large B-cell lymphoma-possible link with monocytic myeloid-derived suppressor cells, Hematol. Oncol. 2013. DOI: 10.1002/hon.2019.
  3. Shin S.J. et al. Prognostic significance of absolute lymphocyte count/absolute monocyte count ratio at diagnosis in patients with multiple myeloma, Korean J. Pathol. 2013. DOI: 10.4132/KoreanJPathol.2013.47.6.526.
  4. Tang L. et al. Effect of absolute monocyte count post-transplant on the outcome of patients with acute myeloid leukemia undergoing myeloablative allogeneic hematopoietic stem cell transplant with busulfan and cyclophosphamide conditioning. Leukemia Research. 2018 Apr 11. DOI: 10.1016/j.leukres.2018.04.006. [Epub ahead of print]