AFF1 and acute lymphoblastic leukemia: Therefore, the diagnostic workflow of the current AIEOP-BFM ALL 2017 study investigates for an extended set of stratification relevant gene fusions (i.e., ETV6-RUNX1, AFF1-KMT2A, and TCF3-HLF) as well as the IKZF1plus subtype [8, 9].