CD 99 expression is strongly associated with clinical outcome in children with B‐cell precursor acute lymphoblastic leukaemia

Our study aimed to determine the expression pattern and clinical relevance of CD 99 in paediatric B‐cell precursor acute lymphoblastic leukaemia ( BCP ‐ ALL ). Our findings demonstrate that high expression levels of CD 99 are mainly found in high‐risk BCP ‐ ALL , e.g. BCR ‐ ABL 1 and CRLF 2 Re/Hi , and that high CD 99 mRNA levels are strongly associated with a high frequency of relapse, high proportion of positive for minimal residual disease at day 29 and poor overall survival in paediatric cohorts, which indicate that CD 99 is a potential biomarker for BCP ‐ ALL .