Clinical relevance of CD10 expression in childhood ALL. The Italian Association for Pediatric Hematology and Oncology (AIEOP)

Abstract

BACKGROUND AND OBJECTIVE: Previous studies have considered the prognostic significance of CD10 expression in childhood acute lymphoblastic leukemia (ALL) and showed its linkage to a more favorable prognosis. The aim of this study was to assess the independent significance of CD10 expression in a large population of ALL patients. DESIGN AND METHODS: We revised the independent clinical relevance of CD10 expression in 2038 children with acute lymphoblastic leukemia (ALL), who were consecutively entered in 4 sequential trials of the Italian Association for Pediatric Hematology and Oncology (i.e. AIEOP studies 82, 87, 88, 91); 1142 were males and 896 females, age ranged between 1 and 14 years (yrs) at diagnosis. Of the whole group, 1471 children (72.2%) were defined as having standard risk, 567 (27.8%) as having a high risk. RESULTS: CD10 was detected in blast cells from 1706 of 1784 (95.6%) patients with B-lineage ALL and 46 of 254 (18.1%) with T-cell ALL. In the B-lineage subgroup CD10 expression was associated with presenting features such as age < 9 yrs and inclusion in the standard risk category. No significant differences were found between CD10+ and CD10- cases in T-lineage ALL, concerning presenting features, except for FAB L2 in the former group. We compared the event-free survival (EFS) rates for patients with T-ALL or B-lineage ALL, regarding CD10 positivity, overall and by individual study. Patients with T-ALL fared worse than those with B-lineage ALL (5 and 10 yrs EFS: 46.8% vs. 68.5% and 44.5% vs. 63.7% respectively, p = 0.0001). In multivariate analysis of B-lineage subgroup poorer EFS was associated with male sex, higher WBC (> or = 20 x 10(9)/L), age > 9 yrs. Only WBC > or = 20 x 10(9)/L and age > 9 yrs were parameters linked to poorer EFS in the T-lineage subgroup. Finally, we compared EFS rates for four groups of patients categorized as having high or standard risk, and according to CD10+ and CD10- expression. High-risk patients fared statistically worse than standard risk patients both in the CD10- and in the CD10+ groups (42% vs. 50.7% and 63.6% vs. 66.8%, respectively). INTERPRETATION AND CONCLUSIONS: CD10 expression does not have independent prognostic significance in either the larger subgroup of B-ALL patients or in T-cell ALL.