ERG and acute lymphoblastic leukemia: To be precise, we propose a “CK2-plus group” for T-ALL: CK2-high, ERG-high, PTEN Exon7 mutation, CDKN2A and IKZF1 deletion identify a subgroup of pediatric T-ALL patients with a very poor outcome, based on the occurrence of a high rate of relapse and/or death due to progressive disease.