幼年型粒单核细胞白血病患者5例临床及基因分析

Clinical and genetic analysis of five children diagnosed with juvenile myelomonocytic leukemia

目的分析幼年型粒单核细胞白血病(JMML)临床特点及基因变异,指导临床工作。方法对临床诊断JMML患儿,用二代测序方法检测JMML相关基因突变,收集临床资料。结果5例患者中,3例检测到PTPN11基因突变,2例检测到KRAS基因突变,均为体细胞杂合错义突变。中位随访时间6月(2~26月),2例PTPN11突变及1例KRAS突变患儿合并出血死亡。1例PTPN11突变患儿行单倍体移植后存活;1例KRAS突变婴儿,对症治疗后病情改善。结论JMML患者多有RAS基因及其调控基因突变,预后差,KRAS体细胞突变不合并高危因素婴儿有自发缓解可能。

Objective To study the clinical and genetic features of juvenile myelomonocytic leukemia(JMML)and guide its treatment.Methods For 5 children with JMML,next-generation sequencing was used to detect common gene mutations of JMML and the clinical data were collected.Results PTPN11 gene mutation was detected in three patients and KRAS gene mutation was detected in the other two patients.All these were somatic heterozygous missense mutations.The median follow-up time of 5 children was 6 months(range 2-26 months).Among five patients,three died because of bleeding,including two cases of PTPN11 gene mutation and one case of KRAS gene mutation.One patient with PTPN11 gene mutation survived after haploid transplantation,and one patient with KRAS gene mutation got better after expectant treatment.Conclusion The mutations of RAS gene and its regulatory genes are usually detected in patients with JMML.The children with JMML often have a poor prognosis.The patients with KRAS gene mutation but not with risk factors may get better spontaneously.