Clinical Study on Dynamic Detection of Minimal Residual Disease in Acute Myeloid Leukemia by Multiparameter Flow Cytometry

Abstract

To investigate the prognostic significance of dynamic detection of minimal residual disease (MRD) in patients with acute myeloid leukemia (AML) by 8-color flow cytometry. MRD of 282 AML patients who achieved remission after initial therapy was detected by 8-color flow cytometry. MRD threshold for predicting recurrence was determined by receiver operating characteristic (ROC) curve, and time from MRD-positive to clinical recurrence was analyzed. The differences in overall survival (OS) time and relapse-free survival (RFS) time of patients with different MRD-changes were compared, and the related factors of recurrence in patients with MRD-negative were analyzed by univariate and logistic regression analysis. ROC curve determined that the MFC-MRD threshold for predicting the recurrence of AML was 0.105%, and the recurrence rate of MRD-positive patients was significantly higher than that of MRD-negative patients [52.45% (75/143 cases) vs 35.97% (50/139 cases), P=0.005]. The patients in MRD persistent positive group and negative to positive group recurred earlier than those in positive to negative group and negative-positive fluctuation group (P<0.005). Survival analysis showed that OS and RFS time of patients with MRD persistent positive were significantly shorter than those of patients with MRD persistent negative, positive to negative, and negative-positive fluctuation (P<0.005). There was no significant difference in OS and RFS between MRD negative to positive group and MRD persistent positive group (P>0.005), either between MRD persistent negative group and MRD positive to negative group (P>0.005). Among 139 MRD-negative patients, 50 recurred. Univariate and logistic regression analysis showed that the risk of recurrence increased with the increase of white blood cells level (95%CI: 1.000-1.013, P=0.045). The risk of recurrence in patients without hematopoietic stem cell transplantation (HSCT) was 9.694 times higher than that in patients who received HSCT (95%CI: 1.720-54.651, P=0.010), and in the high-risk group was 5.848 times higher than that in the low-risk group (95%CI: 1.418-24.121, P=0.015). The prognosis of AML patients with different MRD changes is significantly different. No matter MRD-positive or MRD-negative at the initial remission, dynamic detection of MRD after treatment is more helpful to accurately guide treatment.