免疫表型分析及分子遗传学在急性早幼粒细胞白血病诊断中的应用

OBJECTIVE: To investigate the application values of immunophenotypic analysis and molecular genetics in the diagnosis of acute promyelocytic leukemia (APL). METHODS: The retrospective analyses of flow cytometric (FCM) immunophenotypic anyalysis, chromosome karyotype and chromosome fluorescence in situ hybridization (FISH) of 798 outpatient or hospitalization APL patients referred to our hospital between May 2012 and December 2017 were performed to further study the application values of FCM and molecular genetics in the diagnosis of APL. RESULTS: The sensitivity and specificity of FCM were 91.9% and 98.7% respectively. The typical characteristic immunophenotype for APL was as of follows: a high SSC, absence of expression of cluster differntiation (CD) CD34 and HLA-DR, and expression or stronger expression of CD33, consistent expression of CD13, CD9, CD123, expression of CD56, CD7, CD2 (sometimes). The rest 10% of the cases harbored atypical APL phenotypes, generally accompanied by CD34 and/or HLA-DR expression, decreased SSC and often accompanied by CD2 expression, it was difficult to definitively diagnose APL by this FCM phenotype, and their diagnoses depended on the results of genetics or molecular biology tests. Compared with normal individuals, complex karyotypes APL with t(15;17) translocation, other variant translocations and variant t(11;17), t(5;17) had no significant differences in terms of their FCM phenotypes. CONCLUSION: FCM could rapidly and effectively diagnose APL. Despite the fact that complex karyotypes with various additional chromosomal abnormalities were detected in approximately one third of APL cases in addition to the pathognomonic t(15;17) (q22;q21), they had no observable impact on the overall immunophenotype. Molecular and genetic criteria were the golden criteria for the diagnosis of APL. About 10% of immunophenotyping cases relied on molecular genetics for diagnosis.