PDGFRB and chronic myelogenous leukemia, BCR-ABL1 positive: Imatinib is known to be efficacious in the treatment of other c-KIT mutated haematopoietic and non-haematopoietic neoplasms, such as gastrointestinal stromal tumours (GISTs) and chronic myeloid leukaemia (CML), as well as in patients with SM and coexisting chronic eosinophilic leukaemia (SM-CEL) associated with platelet-derived growth factor (PDGFR) α and β rearrangements [24].