背景:PDGFRB融合在急性淋巴细胞白血病(ALL)中很少见。作者确定了28个儿科PDGFRB阳性ALL。他们分析了特征,结果,和该疾病的预后因素。
方法:这个多中心,回顾性研究纳入了2015年4月至2022年4月在中国20家医院根据CCCG-ALL-2015和CCCG-ALL-2020方案新诊断为PDGFRB融合ALL的6457例儿科患者.在这些病人中,对3451进行PDGFRB融合的筛选。
结果:儿童PDGFRB阳性ALL仅占3451例PDGFRB检测病例的0.8%。这些患者包括21名男性和7名女性,24名B-ALL和4名T-ALL;中位年龄为10岁;基线时白细胞计数中位数为29.8×109/L。只有一名患者有嗜酸性粒细胞增多症。三名患者有IKZF1缺失,三个染色体5q31-33异常,一个人患有复杂的核型。3年无事件生存率(EFS),总生存期(OS),累积复发率(CIR)为33.1%,65.5%,和32.1%,分别,中位随访时间为25.5个月。20例患者接受化疗加酪氨酸激酶抑制剂(TKIs)治疗,8例未接受TKI治疗。完全缓解(CR)率分别为90.0%和63.6%,分别,但是EFS没有区别,操作系统,orCIR.单变量分析显示,IKZF1缺失或可测量的残留病(MRD)≥0.01%的患者诱导后预后较差(p<0.05)。
结论:儿童PDGFRB阳性ALL具有与高风险特征相关的不良结局。化疗加TKIs可以提高CR率,提供较低MRD水平和移植的机会。MRD≥0.01%是一个强有力的不良预后因素,基于MRD的分层治疗可以改善这些患者的生存率.
结论:PDGFRB融合的儿童急性淋巴细胞白血病患者与高风险临床特征相关,如年龄较大,诊断时白细胞计数高,诱导治疗后可测量的高残留疾病,并增加白血病复发的风险。化疗加酪氨酸激酶抑制剂可以提高完全缓解率,并为儿童PDGFRB阳性急性淋巴细胞白血病(ALL)患者提供较低的可测量残留病(MRD)水平和移植的机会。MRD水平也是小儿PDGFRB阳性ALL患者的一个强有力的预后因素。
BACKGROUND: PDGFRB fusions in acute lymphoblastic leukemia (ALL) is rare. The authors identified 28 pediatric PDGFRB-positive ALL. They analyzed the features, outcomes, and prognostic factors of this disease.
METHODS: This multicenter, retrospective study included 6457 pediatric patients with newly diagnosed PDGFRB fusion ALL according to the CCCG-ALL-2015 and CCCG-ALL-2020 protocols from April 2015 to April 2022 in 20 hospitals in
China. Of these patients, 3451 were screened for PDGFRB fusions.
RESULTS: Pediatric PDGFRB-positive ALL accounted for only 0.8% of the 3451 cases tested for PDGFRB. These patients included 21 males and seven females and 24 B-ALL and 4 T-ALL; the median age was 10 years; and the median leukocyte count was 29.8 × 109/L at baseline. Only one patient had eosinophilia. Three patients had an IKZF1 deletion, three had chromosome 5q31-33 abnormalities, and one suffered from a complex karyotype. The 3-year event-free survival (EFS), overall survival (OS), and cumulative incidence of relapse (CIR) were 33.1%, 65.5%, and 32.1%, respectively, with a median follow-up of 25.5 months. Twenty patients were treated with chemotherapy plus tyrosine-kinase inhibitors (TKIs) and eight were treated without TKI. Complete remission (CR) rates of them were 90.0% and 63.6%, respectively, but no differences in EFS, OS, or CIR. Univariate analyses showed patients with IKZF1 deletion or measurable residual disease (MRD) ≥0.01% after induction had inferior outcomes (p < .05).
CONCLUSIONS: Pediatric PDGFRB-positive ALL has a poor outcome associated with high-risk features. Chemotherapy plus TKIs can improve the CR rate, providing an opportunity for lower MRD levels and transplantation. MRD ≥0.01% was a powerful adverse prognostic factor, and stratified treatment based on MRD may improve survival for these patients.
CONCLUSIONS: Pediatric acute lymphoblastic leukemia patients with PDGFRB fusions are associated with high-risk clinical features such as older age, high white blood cell count at diagnosis, high measurable residual disease after induction therapy, and increased risk of leukemia relapse. Chemotherapy plus tyrosine-kinase inhibitors can improve the complete remission rate and provide an opportunity for lower measurable residual disease (MRD) levels and transplantation for pediatric PDGFRB-positive acute lymphoblastic leukemia (ALL) patients. The MRD level was also a powerful prognostic factor for pediatric PDGFRB-positive ALL patients.