Markiewicz Miroslaw, Kopacz Agnieszka, Blajer-Olszewska Beata, Mazur Malwina, Warzybok Katarzyna, Szarawarska Marta, Wojtaszewska Marzena, Moskwa Monika, Dudycz Dominika, Schwarz Ewa, Kosior Katarzyna, Lewandowski Krzysztof
Department of Hematology, Institute of Medical Sciences, College of Medical Sciences, University of Rzeszow, Rzeszow, Poland.
Hematology Department, Frederic Chopin University Clinical Hospital, Rzeszow, Poland.
J Cell Mol Med. 2025 Mar;29(5):e70461. doi: 10.1111/jcmm.70461.
We present a case of acute clonal bone marrow 98% infiltration of atypical myeloid cells with borderline hypogranular/agranular promyelocytes/myelocytes and occasional blast cells maturity, which also formed extramedullary tumours in the chest wall, with isolated trisomy of chromosome 6 and pathogenic variant U2AF1 (S34F) that escapes established acute myeloid leukaemia (AML) diagnostic criteria according to the World Health Organization (WHO) classification. Following standard daunorubicin and cytarabine induction therapy, the disease progressed with the appearance of a previously undetected clone of leukaemic cells with a distinct immunophenotype demonstrating monocytoid differentiation and clonal evolution to a hypo-tetraploid karyotype with an average number of 84 chromosomes and new pathogenic NRAS and ZRSR2 mutations. The patient reactivated refractory disseminated intravascular coagulation (DIC) leading to a progressive supratentorial hematoma and finally cardiac arrest. In conclusion, our report shows that atypical clonal myelocytes can massively infiltrate the bone marrow and form extramedullary tumours, justifying the diagnosis and treatment of acute leukaemia, although they did not fit the current classification.
我们报告了一例急性克隆性骨髓病例，其中98%被非典型髓样细胞浸润，这些细胞具有边缘性低颗粒/无颗粒早幼粒细胞/中幼粒细胞，偶见原始细胞成熟，并且在胸壁形成了髓外肿瘤，伴有6号染色体三体和致病性变异U2AF1（S34F），根据世界卫生组织（WHO）分类，该病例不符合既定的急性髓系白血病（AML）诊断标准。在接受标准的柔红霉素和阿糖胞苷诱导治疗后，疾病进展，出现了一个先前未检测到的白血病细胞克隆，其具有独特的免疫表型，显示单核细胞样分化，并克隆演变为平均有84条染色体的低四倍体核型，同时出现了新的致病性NRAS和ZRSR2突变。患者再次激活了难治性弥散性血管内凝血（DIC），导致进行性幕上血肿，最终心脏骤停。总之，我们的报告表明，非典型克隆性髓细胞可大量浸润骨髓并形成髓外肿瘤，尽管它们不符合当前分类，但仍有理由诊断和治疗急性白血病。
