Prognostic significance of CD20 expression in childhood B-cell precursor acute lymphoblastic leukemia.

CD20 expression is associated with inferior survival in adults with acute lymphoblastic leukemia (ALL). We analyzed the prognostic impact of CD20 expression in 353 children with B-cell precursor ALL treated in 3 consecutive St Jude Total Therapy studies. CD20 expression (> 20%) was found in 169 patients (48%) and was more frequent in patients between 1 and 10 years of age than in those younger than 1 or older than 10 years (P = .001). None of 14 patients with MLL-AF4 expressed CD20. There was no association between CD20 expression and E2A-PBX, TEL-AML1, ploidy, white blood cell count at diagnosis, or sex. In contrast to the experience in adult ALL, our patients with CD20 expression tended to have a better treatment outcome than those without the expression: 5-year event-free survival 84% +/- 2.9% versus 78% +/- 3.1% (P = .08). These data suggest that CD20 expression is not associated with inferior outcome in pediatric patients treated with contemporary regimens.