[Prognostic value of KIT and other clonal genetic mutations in core-binding factor acute myeloid leukemia]

目的

评价基于二代测序（NGS）检测技术下的克隆性基因突变对核心结合因子相关急性髓系白血病（CBF-AML）预后的影响。

方法

回顾性分析2011年7月至2017年8月在苏州大学附属第一医院血液科诊治的195例成人初治CBF-AML患者，其中诱导化疗达完全缓解的患者190例，包括134例RUNX1-RUNXIT1⁺ AML和56例CBFβ-MYH11⁺ AML，年龄15～64岁，中位随访时间43.6个月。采用Log-rank检验和Cox回归模型分析临床因素和基因突变对患者总生存（OS）和无病生存（DFS）的影响。

结果

在195例患者中，KIT基因突变发生率最高（47.6％），其次为NRAS（20.0％）、FLT3（18.4％）、ASXL2（14.3％）、KRAS（10.7％）、ASXL1（9.7％）。按基因功能分类，酪氨酸激酶信号通路基因突变发生率最高（76.4％），其次为染色质修饰相关基因（29.7％）。在接受强化巩固治疗的患者中，CBFβ-MYH11⁺ AML患者的OS有优于RUNX1-RUNXIT1⁺ AML患者的趋势（P＝0.062）。染色质修饰相关基因突变仅在RUNX1-RUNXIT1⁺ AML中检出，但对患者的DFS无明显影响（P＝0.557）。染色质修饰相关基因突变阳性且接受异基因造血干细胞移植（allo-HSCT）的患者预后最好。多因素分析显示KIT exon17突变为影响RUNX1-RUNXIT1⁺ AML患者DFS的独立危险因素（P<0.001），allo-HSCT能明显改善RUNX1-RUNXIT1⁺ AML患者的DFS（P＝0.010）。

结论

合并KIT exon17突变的RUNX1-RUNXIT1⁺ AML患者预后差，allo-HSCT可改善这部分患者的预后，allo-HSCT也能使染色质修饰相关基因突变阳性患者的预后得到改善。

[Impact of KIT D816 mutation on salvage therapy in relapsed acute myeloid leukemia with t(8;21) translocation]

Objective: To evaluate the impact of KIT D816 mutation on the salvage therapy in relapsed acute myeloid leukemia (AML) with t(8;21) translocation. Method: The characteristics of the first relapsed AML with t(8;21) translocation from 10 hospitals were retrospectively collected, complete remission (CR(2)) rate after one course salvage chemotherapy and the relationship between KIT mutation and CR(2) rate was analyzed. Results: 68 cases were enrolled in this study, and 30 cases (44.1%) achieved CR(2). All patients received KIT mutation detection, and KIT D816 mutation was identified in 26 cases. The KIT D816 positive group had significantly lower CR(2) compared with non-KIT D816 group (23.1% vs 57.1%, χ(2)=7.559, P=0.006), and patients with longer CR(1) duration achieved significantly higher CR(2) than those with CR(1) duration less than 12 months (74.1% vs 31.9%, χ(2)=9.192, P=0.002). KIT D816 mutation was tightly related to shorter CR(1) duration. No significant difference of 2 years post relapse survival was observed between KIT D816 mutation and non-KIT D816 mutation group. Conclusion: KIT D816 mutation at diagnosis was an adverse factor on the salvage therapy in relapsed AML with t(8;21) translocation, significantly related to shorter CR1 duration, and can be used for prediction of salvage therapy response. KIT D816 mutation could guide the decision-making of salvage therapy in relapsed AML with t(8;21) translocation.