CSF3R and mixed phenotype acute leukemia: In our cohort of thirteen patients, we identified CSF3R alterations across a variety of myeloid neoplasms, including MDS/MPN-U, AML, MPN with disease progression, MPAL, CMML, and MDS-IB1, suggesting a broader role for CSF3R in pathogenesis of myeloid neoplasms and clonal evolution.