Objective: To analyze the clinical characteristics and prognosis of patients with infant acute lymphoblastic leukemia (IALL). Methods: A retrospective cohort study.Clinical data, treatment and prognosis of 28 cases of IALL who have been treated at Beijing Children's Hospital, Capital Medical University and Baoding Children's Hospital from October 2013 to May 2023 were analyzed retrospectively. Based on the results of fluorescence in situ hybridization (FISH), all patients were divided into KMT2A gene rearrangement (KMT2A-R) positive group and KMT2A-R negative group. The prognosis of two groups were compared. Kaplan-Meier method and Log-Rank test were used to analyze the survival of the patients. Results: Among 28 cases of IALL, there were 10 males and 18 females, with the onset age of 10.9 (9.4,11.8) months. In terms of immune classification, 25 cases were B-ALL (89%), while the remaining 3 cases were T-ALL (11%). Most infant B-ALL showed pro-B lymphocyte phenotype (16/25,64%). A total of 22 cases (79%) obtained chromosome karyotype results, of which 7 were normal karyotypes, no complex karyotypes and 15 were abnormal karyotypes were found. Among abnormal karyotypes, there were 4 cases of t (9; 11), 2 cases of t (4; 11), 2 cases of t (11; 19), 1 case of t (1; 11) and 6 cases of other abnormal karyotypes. A total of 19 cases (68%) were positive for KMT2A-R detected by FISH. The KMT2A fusion gene was detected by real-time PCR in 16 cases (57%). A total of 24 patients completed standardized induction chemotherapy and were able to undergo efficacy evaluation, 23 cases (96%) achieved complete remission through induction chemotherapy, 4 cases (17%) died of relapse. The 5-year event free survival rate (EFS) was (46±13)%, and the 5-year overall survival rate (OS) was (73±10)%.The survival time was 31.3 (3.3, 62.5) months. There was no significant statistical difference in 5-year EFS ((46±14)% vs. (61±18)%) and 5-year OS ((64±13)% vs. (86±13)%) between the KMT2A-R positive group (15 cases) and the KMT2A-R negative group (9 cases) (χ2=1.88, 1.47, P=0.170, 0.224). Conclusions: Most IALL patients were accompanied by KMT2A-R. They had poor tolerance to traditional chemotherapy, the relapse rate during treatment was high and the prognosis was poor.
目的： 分析婴儿急性淋巴细胞白血病（IALL）的临床特征及预后。 方法： 回顾性队列研究。收集2013年10月至2023年5月首都医科大学附属北京儿童医院及保定市儿童医院收治的28例IALL患儿的临床资料、治疗及预后情况，依据荧光原位杂交（FISH）检测结果将患儿分为KMT2A基因重排（KMT2A-R）阳性组与KMT2A-R阴性组并对两组进行预后对比，采用Kaplan-Meier法对患儿进行生存分析并进行Log-Rank检验。 结果： 28例IALL患儿男10例、女18例，发病年龄为10.9（9.4，11.8）月龄。25例为B-ALL（89%），余3例为T-ALL（11%）。婴儿B-ALL大部分为早前B淋巴细胞表型（16/25，64%）。获得染色体核型结果的共22例（79%），7例为正常核型，无复杂核型，15例为异常核型，其中t（9；11）4例、t（4；11）2例、t（11；19）2例、t（1；11）1例，其他异常核型6例。FISH检测KMT2A-R阳性者共19例（68%）。实时定量PCR检测KMT2A融合基因阳性者共16例（57%）。24例患儿完成规范的诱导化疗并可进行疗效评价，诱导化疗完全缓解23例（96%），复发并死亡4例（17%），5年无事件生存率（EFS）为（46±13）%，5年总生存率（OS）为（73±10）%，生存时间31.3（3.3，62.5）个月；KMT2A-R阳性组（15例）与KMT2A-R阴性组（9例）的5年EFS和5年OS差异均无统计学意义［（46±14）%比（61±18）%，（64±13）%比（86±13）%，χ2=1.88、1.47，P=0.170、0.224］。 结论： IALL患儿大多伴有KMT2A-R，传统化疗耐受性差，治疗期间复发率高，预后差。.