目的 探讨儿童急性淋巴细胞白血病（acute lymphoblastic leukemia, ALL）复发的治疗策略及预后因素。 方法 该回顾性队列研究纳入2015—2019年确诊并复发的86例ALL患儿，采用Kaplan‑Meier法及Cox回归模型进行分析。 结果 复发后中位随访36个月，4年生存率为59%。多因素分析（基于接受诱导化疗的子样本）显示，复发高危和诱导治疗后微小残留病（minimal residual disease, MRD）≥0.01%为4年生存率的独立危险因素（P0.05）。2017年进入嵌合抗原受体（chimeric antigen receptor, CAR）‑T细胞治疗时代后，ALL复发患儿4年生存率得到显著改善（61% vs 26%，P=0.030）。根据复发危险度分层：低危患儿接受单纯化疗或CAR‑T均存活；中危者诱导后MRD阴性者化疗存活率高（12/13），而MRD阳性者经CAR‑T联合移植存活率高（7/8）；高危患儿中，接受移植（化疗或CAR‑T后）组存活率为60%~62.5%，显著优于单纯化疗组（0%存活）。CAR‑T后行造血干细胞移植组的4年生存率高于CAR‑T未移植组（75% vs 24%，P=0.067）。 结论 对于ALL复发患儿，推荐基于危险度分层和MRD结合的个体化治疗策略。

Objective To investigate treatment strategies and prognostic factors in children with relapsed acute lymphoblastic leukemia (ALL). Methods A retrospective cohort study enrolled 86 children diagnosed with and relapsed from ALL between 2015 and 2019. Kaplan-Meier method and Cox regression model were applied for analysis. Results The median follow-up after relapse was 36 months. The 4-year overall survival (OS) rate was 59%. Multivariate analysis (based on the subgroup receiving induction chemotherapy) identified high-risk relapse and minimal residual disease (MRD) ≥0.01% after induction therapy as independent risk factors for 4-year OS (P0.05). The introduction of chimeric antigen receptor T-cell (CAR-T) therapy in 2017 significantly improved the 4-year OS rate in children with relapsed ALL (61% vs 26%, P=0.030). According to relapse risk stratification, all low-risk patients survived whether receiving chemotherapy alone or CAR-T therapy. Among intermediate-risk patients, those achieving MRD negativity after re-induction had a high survival rate with chemotherapy (12/13), whereas MRD-positive patients had a high survival rate with CAR-T combined with transplantation (7/8). In high-risk patients, the survival rate for those receiving transplantation (after chemotherapy or CAR-T) was 60% to 62.5%, significantly higher than that of the chemotherapy-alone group (0% survival). The 4-year OS rate for the CAR-T followed by hematopoietic stem cell transplantation group was higher than that of the CAR-T alone group (75% vs 24%, P=0.067). Conclusions An individualized treatment strategy based on risk stratification combined with MRD status is recommended for children with relapsed ALL.