PB1817: PROGNOSTIC SIGNIFICANCE OF CD200 ON ADULT PATIENTS WITH ACUTE MYELOID LEUKEMIA AND ITS MECHANISM

Abstract

Background: The prognostic significance of CD200 expression in adult AML (non-M3) patients is still unknown. Aims: To analyze the prognostic significance of CD200 expression in newly diagnosed adult patients with non-M3 acute myeloid leukemia (AML) in our department, and to explore the effect of CD200 expression on lymphocyte subsets of patients. Methods: The subject was 86 adult patients with AML (non-M3) who were newly diagnosed from April 2018 to December 2020. Clinical information of these patients was collected, and their survival station was followed up to analyze the connection between CD200 and 1-year overall survival (OS) rate. Patients who received chemotherapy were further evaluated, analyzing the relationship between CD200 expression and other clinical characteristics, as well as the relationship between CD200 and complete response (CR) after the first chemotherapy. And the effect of CD200 expression on lymphocyte subsets of patients was analyzed. Results: Of our study of 86 patients, 60 patients were given chemotherapy. These 60 patients were divided into CD200 + AML and CD200 - AML group according to the CD200 expression. There were no differences between CD200+AML group and CD200-AML group in parameters such as gender, age, white blood cell count and proportion of bone marrow blast cells. The difference of CR rate between two groups was statistically significant (p = 0.025). Univariate and multivariate logistic analysis of potential influencing factors for CR rate showed that CD200 was an independent influencing factor for CR rate after the first course of chemotherapy, and the probability of obtaining CR in the CD200 negative group was 4.15 times that of the CD200 positive group (P =0.018). Among them, 30 patients were stratified to moderate risk according to 2021 NCCN guidelines of AML. The CR rate between CD200 negative and CD200 positive subgroups was compared, and the CR rate in the CD200 negative subgroup was higher than that in the CD200 positive subgroup, but there was no statistical significance (P=0.056). There was no difference in 1-year OS rate between the two groups. Among patients included in the study, there was no significant difference in the percentage of T lymphocytes, regulatory T lymphocytes, NK cells and other subsets in WBC between the CD200+AML group and the CD200-AML group. Summary/Conclusion: In summary, our data suggest that CD200 expression in adult AML (non-M3) patients indicated poor CR rate after the first course of chemotherapy, in the follow-up data of this study so far, CD200 had no prognostic significance for 1-year OS rate. There was a correlation between CD200 expression and CR rate in patients of moderate risk, but there was no statistical significance. Moreover, our data suggest that CD200 expression had no significant effect on lymphocyte subsets in patients.