慢性髓系白血病（CML）患者在酪氨酸激酶抑制剂（TKI）停药后仍可能复发，因此需要准确的预测因子来确定有利条件的患者可以进行治疗无放懈（TFR），同时避免无效的尝试。在治疗停药时对总白细胞中残余疾病的敏感检测与复发有关，但鉴于该方法是由不同细胞系的残余白血病组成的综合指标，因此其区分度不高，可能是由于只有某些细胞系与复发有关。我们在符合TKI停药常规标准的48例患者中，从五种细胞分数中追踪测定BCR::ABL1 DNA，作为预测的是/否二元检测。在发生复发的患者中，粒细胞和T细胞中的BCR::ABL1 DNA水平中位数较高，但在其他细胞系中水平并没有升高。在40例进行首次TFR尝试的患者中，我们确定了三个不同复发风险的组别：粒细胞阳性（100%），粒细胞阴性/T细胞阳性（67%），粒细胞阴性/T细胞阴性（25%）。这些数据显示了特定细胞系残余疾病评估在选择可以成功尝试TFR的患者时的重要性，并同时推迟那些很可能复发的患者。版权©2023年美国血液学会。

Chronic myeloid leukemia (CML) patients who are eligible for treatment-free remission (TFR) may still relapse after tyrosine kinase inhibitor (TKI) cessation. There is a need for accurate predictors of outcome to enable patients with a favorable profile to proceed while avoiding futile attempts. Sensitive detection of residual disease in total leukocytes at treatment cessation is associated with relapse, but is not highly discriminatory, likely because it is a composite measure of residual leukemia derived from different cell lineages whereas only some lineages are relevant for relapse. We prospectively measured BCR::ABL1 DNA as a predictive yes/no binary test in five cellular fractions from 48 patients meeting conventional criteria for TKI discontinuation. The median BCR::ABL1 DNA level was higher in granulocytes and in T cells, but not in other lineages, in patients who relapsed. In the 40 patients undergoing a first TFR attempt we defined three groups with differing relapse risk: granulocytes-positive (100%), granulocytes-negative/T cells-positive (67%), and granulocytes-negative /T cells-negative (25%). These data show the critical importance of lineage-specific assessment of residual disease in the selection of patients who can attempt TFR with a high expectation of success, and concurrently defer patients who have a high probability of relapse.Copyright © 2023 American Society of Hematology.