National Cancer Institute Pediatric Oncology Branch, Bethesda, Maryland, USA.
Department of Pediatric Hematology & Oncology, University of Washington, Seattle, Washington, USA.
J Immunother Cancer. 2024 Oct 26;12(10):e009499. doi: 10.1136/jitc-2024-009499.
Lineage switch (LS) refers to the immunophenotypic transformation of one leukemia lineage to another (ie, lymphoid to myeloid) with retention of baseline genetics. This phenomenon was originally observed in infants with B-lymphoblastic leukemia (B-ALL) with rearrangements following chemotherapy, but is now increasingly being observed as a form of immune escape following targeted therapies among children and adults with B-ALL with and without rearrangements. In this report, we present two cases of adolescents with B-ALL harboring rearrangements (Philadelphia-like phenotype) who developed LS to acute myeloid leukemia following CD19 targeted therapy. To our knowledge, these are the first cases of LS to be reported in patients with rearranged acute lymphoblastic leukemia. In addition to raising awareness that this genetic mutation may associate with lineage plasticity, our cases illustrate the importance of multi-modal disease surveillance in the diagnosis of LS.
谱系转换（LS）是指一种白血病谱系向另一种白血病谱系（即淋巴母细胞向髓系）的免疫表型转化，同时保留基线遗传学。这种现象最初在接受化疗后存在重排的婴儿 B 淋巴细胞白血病（B-ALL）中观察到，但现在在接受靶向治疗的儿童和成人 B-ALL 中，无论是否存在重排，作为一种免疫逃避形式，LS 的发生率正在逐渐增加。在本报告中，我们介绍了两例携带重排（费城样表型）的青少年 B-ALL 患者，他们在接受 CD19 靶向治疗后发展为急性髓系白血病。据我们所知，这是首例报道的重排急性淋巴细胞白血病患者发生 LS 的病例。除了提高对这种基因突变可能与谱系可塑性相关的认识外，我们的病例还说明了多模态疾病监测在 LS 诊断中的重要性。
