Clinical Significance of Genetic and Molecular Changes in Primary Myeloid Sarcoma
Objective:To investigate the clinical significance of genetic and molecular changes in primary myeloid sarcoma(MS).Methods:Fourteen patients with primary MS were selected in Jiading District Central Hospital Affiliated Shanghai University of Medicine & Health Sciences,The First People's Hospital of Lianyungang from September 2010 to December 2021.AML1-ETO fusion,PML-RARα fusion and CBFβ breakage were detected by fluorescence in situ hybridization(FISH),and the mutations of NPM1,CEBPA,FLT3,RUNX1,ASXL1,KIT and TP53 genes were detected by new generation sequencing(NGS).Results:Among 14 patients,the MS occurred in bone,breast,epididymis,lung,chest wall,cervix,small intestine,ovary,lymph nodes and central nervous system.The tumor cells expressed MPO(13 cases),CD34(7 cases),CD43(8 cases),CD68(7 cases),CD99(8 cases)and CD117(6 cases).Cytogenetic abnormalities were observed in 4 cases,including 3 cases of AML1-ETO fusion and 1 case of CBF β breakage,while no PML-RAR α fusion was detected.There were no significant differences in overall survival(OS)and leukemia-free survival(LFS)between patients with and without AML1-ETO fusion/CBFβ breakage(both P>0.05).Among the 14 patients,the number of NPM1,CEBPA,FLT3-ITD,RUNX1,ASXL1,KIT and TP53 gene mutations was 5,3,5,3,2,2,1.respectively,of which 7 cases had at least one mutation in FLT3-ITD,RUNX1,ASXL1 and TP53 gene.The OS and LFS of patients with FLT3-ITD,RUNX1,ASXL1 or TP53 mutation were shorter than those without mutations(both P<0.01).Conclusion:The genetic and molecular abnormalities of primary MS can be detected by FISH and NGS techniques.FLT3-ITD,RUNX1,ASXL1 or TP53 mutation indicates a worse prognosis,but further clinical studies are needed to confirm it.