The advantage of HSCT in this setting of patients has been demonstrated in GMALL 04/89 study; indeed, in this study in which HSCT was planned in first CR as intensification after consolidation treatment, no differences in terms of both probability of OS and probability of continuous complete remission (CCR) have been observed between MLL-AF4 positive and negative adult ALL patients [33]. This evidence concerns the gene AFF1 and acute lymphoblastic leukemia.