CD20 is not a poor prognostic factor for childhood B-lineage acute lymphoblastic leukemia with high white blood cell count

Abstract

To study the significance of CD20 combined with white blood cell (WBC) count at diagnosis in the prognosis assessment in children with B-lineage acute lymphoblastic leukemia (ALL). A retrospective analysis was performed on the medical data of 821 B-ALL children who were treated with CCLG-ALL2008 regimen from April 2008 to April 2015. Their survival status was followed up. Among the 821 children, 547 (66.6%) were negative, while 274 (33.4%) were positive for CD20 expression. Among 694 children with WBC<50×109/L (lower WBC count), the 5-year EFS rates were 65.9%±3.2% and 77.3%±2.0% for CD20 positive and negative patients respectively (P=0.001); the 5-year OS rates were 78.3%±2.9% and 87.5%±1.6% for CD20 positive and negative patients respectively (P=0.005); CD20 positive expression was an independent risk factor for EFS (HR=1.634, P=0.001) and OS (HR=1.761, P=0.005). Among 127 children with WBC>50×109/L (higher WBC count), the 5-year EFS rates was 64.3%±7.7% and 53.7%±5.5% for CD20 positive and negative patients respectively (P=0.135); the 5-year OS rate was 81.4%±6.4% and 58.6%±5.6% for CD20 positive and negative patients respectively (P=0.022); CD20 positive expression was an independent protective factor for OS (HR=0.367, P=0.016). In children with B-ALL who are treated with CCLG-ALL2008 regimen, those with CD20 positive expression in lower WBC count at diagnosis have a poor prognosis; however, those with CD20 positive expression in higher WBC count at diagnosis have a better long-time survival.