儿童pro-B急性淋巴细胞白血病的临床特点及预后分析

目的 探究儿童pro-B急性淋巴细胞白血病（pro-B-ALL）的临床特点及预后影响因素。方法 回顾性选择64例年龄 < 18岁的pro-B-ALL患儿为研究对象，分析其临床特点、治疗和预后，以及生存率的影响因素。结果 pro-B-ALL患儿占儿童急性淋巴细胞白血病的6.23%（64/1 028）。64例患儿中男35例，女29例，中位确诊年龄7.0（范围0.4~16.0）岁，其中≥ 10岁和 < 1岁者分别占39%和6%，中位初诊白细胞计数25.5（范围0.4~831.9）×10⁹/L，其中≥ 50×10⁹/L者占35.9%。MLL-r阳性是最常见的分子遗传学异常（34%，22/64），常伴CD22、CD13低表达和CD7高表达，其中MLL-AF4阳性者常伴CD33低表达。64例患儿中位随访时间60.0（范围4.9~165.3）个月，5年总生存（OS）率及无事件生存（EFS）率分别为（85±5）%和（78±5）%。多因素分析显示，化疗3个月微小残留病≥ 0.1%是影响pro-B-ALL患儿5年OS率和EFS率的独立危险因素（P < 0.05）。结论 儿童pro-B-ALL具有独特的临床和生物学特征。初诊时的免疫抗原、分子遗传学异常及化疗3个月微小残留病水平是影响远期疗效的重要因素。

Clinical characteristics and prognostic analysis of pediatric pro-B cell acute lymphoblastic leukemia

Objective To explore the clinical-biological characteristics and prognosis of pediatric pro-B cell acute lymphoblastic leukemia (pro-B-ALL). Methods A total of 64 patients aged less than 18 years old with pro-BALL were enrolled. Clinical characteristics, therapeutic effect and prognostic factors were retrospectively analyzed. Results Pro-B-ALL occurred in 6.23% (64/1 028) of pediatric ALL. Among the 64 patients, 35 were male and 29 were female. The median age was 7.0 years (range 0.4-16.0 years) at diagnosis, of which 39% and 6% were ≥ 10 years old and < 1 year old respectively. The median WBC count was 25.5×10⁹/L[range (0.4-831.9)×10⁹/L], of which 35.9% were ≥ 50×10⁹/L. MLL-r positivity was the most frequent genetic alteration in pro-B ALL, occurring in 34% of patients, with lower frequency of CD22 and CD13 expression and higher frequency of CD7 expression, while lower frequency of CD33 expression was found in patients with MLL-AF4 positivity. At a median follow-up of 60.0 months (range 4.9-165.3 months), the estimated 5-year overall survival (OS) and event-free survival (EFS) in the 64 patients were (85±5)% and (78±5)% respectively. Cox proportional hazards regression analysis identified MRD ≥ 0.1% at 3 months after chemotherapy as an independent adverse prognostic factor for both 5-year OS and EFS. Conclusions Pediatric pro-B ALL is a heterogeneous disease with clinical and biological diversity. Biological characteristics, such as immunological markers, genetic alterations, and MRD at 3 months after chemotherapy may be important factors for the long-term prognosis.