目的 探讨伴有RAS突变的幼年型粒单核细胞白血病（juvenile myelomonocytic leukemia, JMML）的基因组特征和预后因素。 方法 回顾性分析2008年1月—2022年11月中国医学科学院血液病医院诊治的具有RAS突变的JMML患儿的临床资料。 结果 共纳入34例患儿，其中单纯NRAS突变17例（50%），单纯KRAS突变9例（27%），复合突变8例（24%）。与NRAS单纯突变的患儿比较，NRAS复合突变的患儿发病年龄、血小板计数及胎儿血红蛋白比例等方面差异有统计学意义（P<0.05）。Cox比例风险回归模型分析显示，造血干细胞移植（hematopoietic stem cell transplantation, HSCT）和肝大（≥肋下2 cm）是影响RAS突变的JMML患儿生存率的因素（P<0.05）；肝大是影响非HSCT组JMML患儿生存率的因素（P<0.05）。 结论 NRAS复合突变患儿发病年龄晚于NRAS单纯突变患儿。NRAS复合突变患儿在初诊时，外周血小板和胎儿血红蛋白情况较NRAS单纯突变患儿更差。初诊时肝脏大小与RAS突变JMML患儿预后有关。HSCT可改善RAS突变JMML患儿预后。

Objective To investigate the genomic characteristics and prognostic factors of juvenile myelomonocytic leukemia (JMML) with RAS mutations. Methods A retrospective analysis was conducted on the clinical data of JMML children with RAS mutations treated at the Hematology Hospital of Chinese Academy of Medical Sciences, from January 2008 to November 2022. Results A total of 34 children were included, with 17 cases (50%) having isolated NRAS mutations, 9 cases (27%) having isolated KRAS mutations, and 8 cases (24%) having compound mutations. Compared to children with isolated NRAS mutations, those with NRAS compound mutations showed statistically significant differences in age at onset, platelet count, and fetal hemoglobin proportion (P<0.05). Cox proportional hazards regression model analysis revealed that hematopoietic stem cell transplantation (HSCT) and hepatomegaly (≥2 cm below the costal margin) were factors affecting the survival rate of JMML children with RAS mutations (P<0.05); hepatomegaly was a factor affecting survival in the non-HSCT group (P<0.05). Conclusions Children with NRAS compound mutations have a later onset age compared to those with isolated NRAS mutations. At initial diagnosis, children with NRAS compound mutations have poorer peripheral platelet and fetal hemoglobin levels than those with isolated NRAS mutations. Liver size at initial diagnosis is related to the prognosis of JMML children with RAS mutations. HSCT can improve the prognosis of JMML children with RAS mutations.