儿童急性B前体淋巴细胞白血病CD20表达与临床特征及预后的相关性研究

Expression of CD20 in B-cell Precursor Acute Lymphoblastic Leukemia and Its Correlation with Clinical Outcomes

中文关键词:  B前体细胞急性淋巴细胞白血病 CD20 临床特征 预后 儿童

英文关键词:B-cell precursor acute lymphoblastic leukemia CD20 Clinical features Prognosis Children

中文摘要:

      目的 探讨CD20表达与儿童急性B前体淋巴细胞白血病（BCP-ALL）临床特征和预后的关系。方法 研究对象为我院2009年1月至2013年5月收治的271例初诊儿童BCP-ALL，统一按中国儿童白血病协作组ALL 2008方案规范化分型治疗并长期随访。统计分析CD20阳性（CD20⁺BCP）和CD20阴性（CD20^-BCP）ALL的临床特征、早期治疗反应和预后情况。结果 CD20⁺BCP占本组BCP-ALL的45.76%（124例）。CD20⁺BCP与CD20^-BCP在性别构成比、初诊中位年龄、初诊外周血白细胞中位计数、泼尼松不敏感比例和临床危险度病例分布的差异均无统计学意义（P均>0.05）。CD20⁺BCP和CD20^-BCP组中≥10岁的病例分别占25.81%和14.29%（P=0.017），pro-B和pre-B病例比例分别为43.55%、59.86%和56.45%、40.14%（P=0.007），BCR-ABL阳性病例比例分别为12.20%和4.86％（P=0.03），TEL-AML1阳性病例比例分别为6.50％和18.06％（P=0.005）。两组患儿诱导化疗第15 d和第33 d骨髓完全缓解率分别为77.50%（93／120）和74.13%（106／143），95.04%（115／121）和95.83%（138／144）（P均>0.05），4年无事件生存（EFS）率分别为78.00%±4.96%和79.05%±5.40%，4年总生存（OS）率分别为83.01%±6.13%和93.64%±2.46%（P均>0.05）。结论 CD20阳性表达与儿童BCP-ALL预后无明确相关性，尚不能作为判断儿童BCP-ALL不良预后的指标。CD20靶向免疫治疗在儿童BCP-ALL的应用尚需深入研究。

英文摘要:

      Objective To determine whether expression of CD20 is associated with clinical outcomes of childhood B-cell precursor acute lymphoblastic leukemia (BCP-ALL). Methods 271 newly diagnosed childhood BCP-ALL during January 2009 to May 2013 were enrolled in this study.The patients were treated in line with the Chinese Childhood Leukemia Group ALL 2008 protocol (CCLG-ALL 2008). The clinical feature, early therapeutic response and clinical outcomes of the patients with a CD20 positive (CD20⁺BCP) expression were compared with those with a CD20 negative (CD20^-BCP) expression. Results CD20⁺BCP accounted for 45.76% (124 cases) of all participants. There were no significant differences between CD20⁺BCP and CD20^-BCP patients in gender distribution, age,WBC counts when diagnosis was made, proportion of prednisone poor responders, and distribution of risk categories (P>0.05). Patients of 10 years or older comprised 25.81% and 14.29% of CD20⁺BCP and CD20^-BCP patients, respectively (P=0.017). Pro-B and pre-B cases accounted for 43.55% and 59.86% of CD20⁺BCP patients respectively, compared with 56.45 and 40.14% in CD20^-BCP patients (P=0.007). CD20⁺BCP patients had 12.20% Philadelphia positive ALL and 6.50% BCP-ALL with TEL-AML1 fusion gene,compared with 4.86%(P=0.03) and 18.06% (P=0.005) in those of CD20^-BCP. No significant differences were found between the two groups of patients in 15-day (77.50% vs. 74.13%, P=0.525) and 33-day (95.04% vs. 95.83%, P=0.757) complete remission rates. No significant differences (P>0.05) were found in predicted 4-year event-free survival 〔EFS (78.00%±4.96%) vs. (79.05%±5.40%)〕 and predicted 4-year overall survival 〔OS (83.01%±6.13%) vs. (93.64%±2.46%)〕 between the two groups of patients either. Conclusion CD20 positivity was not found to be associated with worse prognosis of children with BCP-ALL. More studies are needed to validate the correlation between CD20 and unfavorable outcomes in BCP-ALL.