联合间期和中期荧光原位杂交检测发现11q23异常伴D13S319缺失急性髓系白血病一例

目的对1例出现11q23异常伴D13S319缺失的罕见急性髓系白血病(acute myeloid leukemia,AML)患者进行多途径细胞遗传学分析,为诊断、治疗及预后分层提供依据。方法应用G+R显带技术对患者24 h培养后的中期分裂相进行染色体核型分析,联合分裂间期和中期荧光原位杂交(fluorescence in situ hybridization,FISH)技术对患者染色体的特定位点进行检测,明确复杂易位和微小缺失片段。结果患者存在混合系白血病基因(mixed lineage leukemia,MLL)重排,形成了MLL-AF10融合基因,并伴有13号染色体D13S319位点的缺失。结论MLL基因重排合并D13S319位点缺失在急性白血病中是否具有双重打击效应应引起临床的重视。在AML患者核型中发现13q-、del(13)(q14)、-13或der(13)任意一种克隆性异常时,应行FISH检测论证及明确缺失片段的大小,以便进行靶向治疗。

An acute myeloid leukemia case with concurrent 11q23 anomaly and D13S319 deficiency diagnosed by combined inter-and metaphase fluorescence in situ hybridization

Objective To carry out multipath cytogenetic analysis of a rare case of acute myeloid leukemia(AML)with 11q23 aberration and D13S319 deletion.Methods G+R banding technique was used to analyze the chromosomal karyotype of the patient after 24 h of cell culture.Combined interphase and metaphase fluorescence in situ hybridization(FISH)was used to detect specific chromosomal sites for complex translocations and minor missing fragments.Results The patient was found to harbor MLL-AF10 fusion gene due to rearrangement of the mixed lineage leukemia(MLL)gene in conjunct with deletion of the D13S319 locus on chromosome 13.Conclusion Whether MLL gene rearrangement and absence of D13S319 locus has a double impact on AML should attract more attention.For AML patient with clonal abnormalities such as 13q-,del(13)(q14),-13 or der(13),FISH assay should be proof and considered to determine the size of missing fragment so as targeted therapy may be implemented.