CD27 and acute lymphoblastic leukemia: ETV6-RUNX1-like ALL (found in almost 3% of pediatric ALL cases) shares a similar gene expression profile and immunophenotype (CD27+, CD44 low/negative) to ETV6-RUNX1 ALL, with a relatively favorable prognosis, but it is characterized by ETV6 and IKZF1 aberrations [76].