目的 评估异基因造血干细胞移植(allo-HSCT)联合化疗治疗儿童髓系肉瘤(MS)的疗效。方法 回顾性分析于血液肿瘤中心确诊并治疗的7例MS患儿临床资料。结果 7例MS患儿中，男3例，女4例；诊断中位年龄5岁2个月；1例以“局部包块”就诊，6例在确诊急性髓细胞性白血病（AML）后发现存在髓外浸润；MS浸润部位包括头面部（4例）、纵隔（2例）、髂骨（1例）。7例患者均接受CCLG-AML-2019方案化疗并桥接allo-HSCT治疗。移植前均接受清髓预处理，其中5例采用后置环磷酰胺（PTCY），2例采用经典白消安联合环磷酰胺（BUCY）方案。7例患儿均回输G-CSF动员后采集的外周血造血干细胞，回输单个核细胞（MNC）中位数19.87×10⁸/kg，CD34⁺细胞中位数12.87×10⁶/kg。 中性粒细胞植入中位时间+15（13~15） d，血小板植入中位时间+12（11~17）d。随访截至2025年6月30日，中位随访时间1 008（371~1 814）d，5例存活，2例复发后死亡。无移植相关死亡发生，预计3年OS为71%。结论 早期诊断儿童MS仍存在挑战，规范化疗并尽早桥接allo-HSCT对部分患者能获得相对较好的疗效。

Objective To explore the efficacy of allogeneic hematopoietic stem cell transplantation (allo-HSCT) combined with chemotherapy in children with myeloid sarcoma (MS). Methods A retrospective analysis was conducted on the clinical diagnosis, treatment and follow-up data of 7 children with MS who were diagnosed and treated at the hematology and oncology center from January 1, 2020 to December 31, 2023. Results There were 3 male and 4 female patients included in this study. The median age of diagnosis was 62 months (10 months - 14 years). Of the 7 patients, only 1 was initially presented with a "local mass," while the remaining 6 were diagnosed with acute myeloid leukemia (AML) and subsequently discovered to have extramedullary involvement, including 4 in the head and face, 2 in the mediastinum, and 1 in the ilium. All 7 patients received CCLG-AML-2019 protocol-based chemotherapy and bridging allo-HSCT. All children received a myeloablative pretreatment regimen prior to transplantation. Five of the 7 children were treated with post-infusion cyclophosphamide (PTCY), and 2 with busulfan combined with cyclophosphamide (BUCY). The median number of mononuclear cells infused was 19.87 (7.4-24.28)×10⁸/kg, and the median number of CD34⁺ cells infused was 12.87 (7.1-14.7)×10⁶/kg. The median time of neutrophil engraftment was +15(13-15) days, and the median time of platelet engraftment was +12(11-17) days. As of June 30, 2025, The median follow-up time was 1008 (371-1814) d. Five patients were alive, and 2 died. There was no death related to allo-HSCT. The estimated 3-year OS rate was 71%. Conclusion There are still challenges in the early diagnosis of MS in children, and the standard chemotherapy bridging allo-HSCT in the treatment of MS in children can obtain better efficacy.