PBX1 and acute lymphoblastic leukemia: In addition, the complex genomic profile of ALL with intrachromosomal amplification of chromosome 21 (iAMP21-ALL, n = 3), and in-frame gene fusions of KMT2A-r (n = 8), ETV6::RUNX1 (n = 5) and TCF3::PBX1 (n = 3), were consistently identified using T-N and T-only approaches.