SSBP2-CSF1RIs a Recurrent Fusion in B-Other Acute Lymphoblastic Leukaemia with Variable Clinical Outcome

BCR-ABL1-like acute lymphoblastic leukaemia (ALL) is a subgroup of B cell precursor (BCP) ALL, which has a similar gene expression profile to BCR-ABL1positive ALL and shares the same high risk of relapse. BCR-ABL1-like ALL is genetically heterogeneous and no single abnormality defines them. However a number of novel fusion genes have been reported in this subgroup, which involve the kinase genes: PDGFRB, CSF1R, ABL1, ABL2and JAK2. Studies have shown that patients with these fusions may also respond to tyrosine kinase inhibitors (TKI), such as imatinib. Here we present a subset of patients with the SSBP2-CSF1Rfusion, including a patient treated with imatinib after relapse.