Определение порогового значения минимальной остаточной болезни у пациентов с острыми миелоидными лейкозами, получающих лечение по протоколам «ОМЛ-17» и «mОМЛ-17»

BACKGROUND. Minimal residual disease (MRD) refers to the tumor cells detected in complete remission patients by highly sensitive methods (PCR and flow cytometry). Each treatment regimen requires the determination of MRD threshold, i.e., the leukemic cell count used for prognostic stratification of patients. AIM. To determine the MRD threshold in acute myeloid leukemia (AML) treated with ‘ОМЛ-17’ and ‘mОМЛ-17’ regimens. MATERIALS & METHODS. The study enrolled 73 AML patients (age ≤ 60 years). MRD was assessed by multicolor flow cytometry after induction cycles 1 and 2. Statistical analysis included Kaplan-Meier curve for assessing disease-free survival and ROC-survival curve for assessing MRD threshold. RESULTS. Complete remission was achieved in 89.1 % of patients. MRD-negative status was reported after induction cycle 1 in 66.7 % of patients and after cycle 2 in 74.6 % of patients. By the ROC-survival curve, the MRD threshold values were determined as 0.1 % after induction cycle 1 and 0.03 % after cycle 2. With the threshold 0.1 %, the 3-year overall survival after induction cycle 1 was 47.1 % in patients with the MRD-positive status vs. 96.9 % in patients with the MRD-negative status, whereas after induction cycle 2 they were 85.8 % and 51.8 %, respectively. CONCLUSION. Based on MRD monitoring after induction cycles 1 and 2 with ‘ОМЛ-17’ and ‘mОМЛ-17’ regimens, a group of patients at high risk for relapse can be identified. Critical MRD thresholds are 0.1 % after induction cycle 1 and 0.03 % after cycle 2.