Recently, we defined “CML-like” subtype of BCR::ABL1-positive acute lymphoblastic leukemia (ALL), resembling lymphoid blast crisis of chronic myeloid leukemia (CML). Here we retrospectively analyzed prognostic relevance of minimal residual disease (MRD) and other features in 147 children with BCR::ABL1-positive ALL (diagnosed I/2000–IV/2021, treated according to EsPhALL (n = 133) or other (n = 14) protocols), using DNA-based monitoring of BCR::ABL1 genomic breakpoint and clonal immunoglobulin/T-cell receptor gene rearrangements. Although overall prognosis of CML-like (n = 48) and typical ALL (n = 99) was similar (5-year-EFS 60% and 49%, respectively; 5-year-OS 75% and 73%, respectively), typical ALL presented more relapses while CML-like patients more often died in the first remission. Prognostic role of MRD was significant in the typical ALL (p = 0.0005 in multivariate analysis for EFS). In contrast, in CML-like patients MRD was not significant (p values > 0.2) and inapplicable for therapy adjustment. Moreover, in the typical ALL, risk-prediction could be further improved by considering initial hyperleukocytosis. Early distinguishing typical BCR::ABL1-positive ALL and CML-like patients is essential to enable optimal treatment approach in upcoming protocols. For the typical ALL, tyrosine-kinase inhibitors and concurrent chemotherapy with risk-directed intensity should be recommended; in the CML-like disease, no relevant prognostic feature applicable for therapy tailoring was found so far.

最近，我们定义了 BCR::ABL1 阳性急性淋巴细胞白血病 (ALL) 的“CML 样”亚型，类似于慢性粒细胞白血病 (CML) 的淋巴母细胞危象。在这里，我们回顾性分析了 147 名 BCR::ABL1 阳性 ALL 儿童（诊断为 I/2000–IV/2021，根据 EsPhALL (n = 133) 或其他 ( n  = 14) 方案），使用基于 DNA 的 BCR::ABL1 基因组断点和克隆免疫球蛋白/T 细胞受体基因重排监测。尽管 CML 样 ( n  = 48) 和典型 ALL ( n  = 99) 的总体预后相似（5 年 EFS 分别为 60% 和 49%；5 年 OS 分别为 75% 和 73%），典型的 ALL 出现更多的复发，而 CML 样患者更常在第一次缓解时死亡。MRD 在典型 ALL 中的预后作用非常重要（ EFS 多变量分析中p = 0.0005）。相反，在 CML 样患者中，MRD 不显着（p值 > 0.2）并且不适用于治疗调整。此外，在典型的 ALL 中，通过考虑初始白细胞增多症可以进一步改善风险预测。早期区分典型的 BCR::ABL1 阳性 ALL 和 CML 样患者对于在即将推出的方案中实现最佳治疗方法至关重要。对于典型的ALL，应推荐酪氨酸激酶抑制剂和具有风险导向强度的同步化疗；在类 CML 疾病中，迄今为止尚未发现适用于治疗调整的相关预后特征。