Alterations of TP53 are associated with poor outcome in relapsed childhood acute lymphoblastic leukemia

Prognosis of children with relapsed ALL has improved by treatment protocols using clinical markers. Further improvement will rely on the identification of molecular markers. Inactivation of the TP53 gene in cancer is associated with poor outcome. However, its role in relapsed ALL is still controversial. To clarify the significance of TP53 inactivation, we analysed 159 patients with first relapse enrolled in the ALL-REZ BFM 2002 trial for copy number and sequence alteration of the TP53 gene. TP53 alterations were observed in 17.46% (22/126) of relapsed B-cell precursor (BCP) and 18.18% (6/33) of relapsed T-cell A…