8p11骨髓增生性肿瘤综合症是一种罕见的造血系统恶性肿瘤，由FGFR1易位引起。患者表现为骨髓增生性肿瘤，通常会演变成急性髓系白血病或T淋巴母细胞淋巴瘤/白血病。本文报道一例8p11骨髓增生性肿瘤综合症患者的分子研究，该患者发展为急性B淋巴母细胞白血病，然后转化为混合表型急性白血病。一名67岁的女性被诊断为具有t（6;8）（q27; p12）的骨髓增生性肿瘤，并接受了红细胞增多症的监测。四年后，她发展为急性B淋巴母细胞白血病，还有一个额外的染色体异常，即- 7。尽管接受了两个诱导疗程，但她未能实现完全缓解，白血病转化为混合表型白血病。对序列骨髓样本进行靶向测序，发现转化为B细胞白血病时存在RUNX1 L144R突变。在这两个诱导疗程之后，一些RUNX1突变阳性的白血病细胞获得了JAK2 V617F突变，这与髓系标记物的出现有关，包括髓过氧化物酶。©2023，作者。

8p11 myeloproliferative syndrome is a rare hematological malignancy caused by the translocation of FGFR1. Patients present with a myeloproliferative neoplasm that frequently transforms into acute myeloid leukemia or T-lymphoblastic lymphoma/leukemia. Here, we report a molecular study of a patient with 8p11 myeloproliferative syndrome who developed acute B-lymphoblastic leukemia and then transformed to mixed-phenotype acute leukemia. A 67-year-old woman was diagnosed with a myeloproliferative neoplasm with t(6;8)(q27;p12) and was monitored for polycythemia vera. Four years later, she developed acute B-lymphoblastic leukemia with an additional chromosomal abnormality of - 7. Despite two induction regimens, she failed to achieve complete remission, and leukemia transformed into mixed-phenotype leukemia. Targeted sequencing of serial bone marrow samples identified the RUNX1 L144R mutation upon transformation to B-cell leukemia. After those two induction regimens, some RUNX1 mutation-positive leukemic cells obtained the JAK2 V617F mutation, which was associated with the emergence of myeloid markers, including myeloperoxidase.© 2023. The Author(s).