Objective: To analyze the clinical features, efficacy and prognosis factors of core binding factor (CBF) acute myeloid leukemia (AML) children in South China. Methods: This was a retrospective cohort study. Clinical data of 584 AML patients from 9 hospitals between January 2015 to December 2020 was collected. According to fusion gene results, all patients were divided into two groups: CBF-AML group (189 cases) and non-CBF-AML group (395 cases). CBF-AML group were divided into AML1-ETO subgroup (154 cases) and CBFβ-MYH11 subgroup (35 cases). Patients in CBF-AML group chosen different induction scheme were divided into group A (fludarabine, cytarabine, granulocyte colony stimulating factor and idarubicin (FLAG-IDA) scheme, 134 cases) and group B (daunorubicin, cytarabine and etoposide (DAE) scheme, 55 cases). Age, gender, response rate, recurrence rate, mortality, molecular genetic characteristics and other clinical data were compared between groups. Kaplan-Meier method was used for survival analysis and survival curve was drawn. Cox regression model was used to analyze prognostic factors. Results: A total of 584 AML children were diagnosed, including 346 males and 238 females. And a total of 189 children with CBF-AML were included, including 117 males and 72 females. The age of diagnosis was 7.3 (4.5,10.0)years, and the white blood cell count at initial diagnosis was 21.4 (9.7, 47.7)×109/L.The complete remission rate of the first course (CR1) of induction therapy, relapse rate, and mortality of children with CBF-AML were significantly different from those in the non-CBF-AML group (91.0% (172/189) vs. 78.0% (308/395); 10.1% (19/189) vs. 18.7% (74/395); 13.2% (25/189) vs. 25.6% (101/395), all P<0.05). In children with CBF-AML, the CBFβ-MYH11 subgroup had higher initial white blood cells and lower proportion of extramedullary invasion than the AML1-ETO subgroup, with statistical significance (65.7% (23/35) vs. 14.9% (23/154), 2.9% (1/35) vs. 16.9% (26/154), both P<0.05). AML1-ETO subgroup had more additional chromosome abnormalities (75/154), especially sex chromosome loss (53/154). Compared with group B, group A had more additional chromosome abnormalities and a higher proportion of tumor reduction regimen, with statistical significance (50.0% (67/134) vs. 29.1% (16/55), 34.3% (46/134) vs. 18.2% (10/55), both P<0.05). Significant differences were found in 5-years event free survival (EFS) rate and 5-year overall survival (OS) rate between CBF-AML group and non-CBF-AML group ((77.0±6.4)%vs. (61.9±6.7)%,(83.7±9.0)%vs. (67.3±7.2)%, both P<0.05).EFS and OS rates of AML1-ETO subgroup and CBFβ-MYH11 subgroup in children with CBF-AML were not significantly different (both P>0.05). Multivariate analysis showed in the AML1-ETO subgroup, CR1 rate and high white blood cell count (≥50×109/L) were independent risk factors for EFS (HR=0.24, 95%CI 0.07-0.85,HR=1.01, 95%CI 1.00-1.02, both P<0.05) and OS (HR=0.24, 95%CI 0.06-0.87; HR=1.01, 95%CI 1.00-1.02; both P<0.05). Conclusions: In CBF-AML, AML1-ETO is more common which has a higher extramedullary involvement and additional chromosome abnormalities, especially sex chromosome loss. The prognosis of AML1-ETO was similar to that of CBFβ-MYH11. The selection of induction regimen group FLAG-IDA for high white blood cell count and additional chromosome abnormality can improve the prognosis.
目的： 分析华南地区儿童核心结合因子（CBF）相关急性髓系白血病（AML）的临床特征及预后相关因素。 方法： 回顾性队列研究。分析2015年1月至2020年12月华南急性髓系白血病协作组的9个医学中心确诊的584例初诊AML患儿的临床资料，根据融合基因结果分为CBF-AML组（189例）与非CBF-AML组（395例），其中CBF-AML组患儿分为AML1-ETO亚组（154例）与CBFβ-MYH11亚组（35例），根据诱导方案非随机选择结果分为A组［FLAG-IDA（氟达拉滨+去甲氧柔红霉素+阿糖胞苷+粒细胞集落刺激因子）方案，134例］及B组［DAE方案（柔红霉素+阿糖胞苷+依托泊苷），55例］，分析各组患儿的年龄、性别、缓解率、复发率、病死率、分子遗传特征等临床资料并进行组间比较，采用Kaplan-Meier法进行生存分析并绘制生存曲线，Cox回归模型进行预后因素分析。 结果： 584例AML患儿中男346例、女238例，其中CBF-AML患儿共189例，男117例、女72例，诊断年龄为7.3（4.5，10.0）岁，初诊时白细胞计数为21.4（9.7，47.7）×109/L，CBF-AML患儿第1个疗程诱导治疗完全缓解率、复发率及病死率与非CBF-AML组相比，差异均有统计学意义［91.0%（172/189）比78.0%（308/395），10.1%（19/189）比18.7%（74/395），13.2%（25/189）比25.6%（101/395），均P<0.05］。CBF-AML患儿中CBFβ-MYH11亚组与AML1-ETO亚组相比，初发白细胞计数≥50×109/L的比例更高，髓外浸润比例更低，差异均有统计学意义［65.7%（23/35）比14.9%（23/154），2.9%（1/35）比16.9%（26/154），均P<0.05］，AML1-ETO亚组容易发生附加染色体异常（75/154），其中性染色体缺失最常见（53/154）。与B组相比，A组附加染色体异常及使用减瘤方案的比例更高，差异均有统计学意义［50.0%（67/134）比29.1%（16/55），34.3%（46/134）比18.2%（10/55），均P<0.05］。CBF-AML组5年无事件生存率（EFS）、5年总生存率（OS）均优于非CBF-AML组［（77.0±6.4）%比（61.9±6.7）%，（83.7±9.0）%比（67.3±7.2）%，均P<0.05］。CBF-AML患儿中AML1-ETO亚组与CBFβ-MYH11亚组的EFS及OS差异均无统计学意义（均P>0.05）。AML1-ETO亚组患儿多因素分析显示第1次完全缓解率和初始白细胞计数高（≥50×109/L）均是影响EFS［HR=0.24，95%CI 0.07~0.85；HR=1.01，95%CI 1.00~1.02；均P<0.05］及OS［HR=0.24，95%CI 0.06~0.87；HR=1.01，95%CI 1.00~1.02；均P<0.05］的独立危险因素。 结论： 儿童CBF-AML以AML1-ETO为主，有更高的髓外浸润，容易发生附加染色体异常，尤其是性染色体缺失，AML1-ETO与CBFβ-MYH11患儿预后相当。针对白细胞计数高及附加染色体异常患儿，选择诱导方案FLAG-IDA可改善预后。.