Negative expression of CD117 predicted inferior OS and PFS in acute promyelocytic leukemia.

Introduction: In recent years, the correlation between CD117 antigen and the prognosis of hematological malignancies has been demonstrated. However, there is limited literature on the clinical significance of CD117 antigen in acute promyelocytic leukemia (APL). The aim of this study was to retrospectively analyze the clinical features and prognostic significance of CD117 in APL.

Methods: In this study, we retrospectively investigated the clinicopathological characteristics, outcome, and prognostic impact of negative CD117 expression (CD117^-) in 169 APL patients treated with all-trans retinoic acid (ATRA) and arsenic trioxide (ATO) containing regimen.

Results: The median follow-up period was 63.0 months. CD117^- was detected in 13 APL patients (7.7%). No significant differences were found in baseline characteristics between CD117+ and CD117^- subgroups. However, compared to CD117+ APL, the incidence of early death (ED) was significantly higher in CD117^- APL (p = 0.023). By multivariate analysis, CD117- was an independent adverse prognostic factor for overall survival (OS) and progression-free survival (PFS) (p = 0.022 and p = 0.014, respectively).

Conclusions: To sum up, CD117^- is associated with greater risk of ED and has the statistical power to predict inferior OS and PFS, this marker may be considered to build prognostic scores for risk-adapted therapeutic strategies in APL management.