Only SETBP1 hotspot mutations are associated with refractory disease in myeloid malignancies

Introduction SETBP1 mutations have been established as a diagnostic marker in myeloid malignancies and are associated with inferior survival. Since there is limited data on their clinical impact and stability during disease progression, we sought to investigate the relationship between SETBP1 mutations and disease evolution. Methods Bidirectional Sanger sequencing of the SETBP1 gene was performed for 442 unselected patients with World Health Organization (WHO) defined myeloid disorders. Follow-up analysis was performed on samples from 123/442 patients to investigate SETBP1 mutation dynamics. Targeted deep next-generation sequencing for a panel of 30 leukemia-associated genes was established to study SETBP1 cooperating mutations. Results 10/442 patients (2.3%) had SETBP1 hotspot mutations (MDS/MPN, n = 7, sAML, n = 3), whereas four patients (1%) had SETBP1 non-hotspot mutations (MPN, n = 1; MDS, n = 2; sAML, n = 1). The median overall survival for patients with SETBP1 hotspot mutations, SETBP1 non-hotspot mutations, and SETBP1 wild type was 14 (range 0–31), 50 (range 0–71), and 47 months (range 0–402), respectively. In Kaplan–Meier analysis, SETBP1 hotspot mutations were significantly associated with reduced overall survival compared to SETBP1 non-hotspot mutations and the SETBP1 wild type ( p