Two myeloid leukemia cases with rare FLT3 fusions

• DOI: 10.1101/mcs.a003079
• Publication Date: 2018-12-17T19:49:20Z
• Authors: Haijiao Zhang; Aleksandra Paliga; Evie Hobbs; Stephen Moore; Susan Olson; Nicola Long; Kim-Hien T. Dao; Jeffrey W. Tyner
• Keywords: Research Report; Male; Recombination, Genetic; Lymphoma; Proto-Oncogene Proteins c-ets; Phenylurea Compounds; Leukemia, Myelomonocytic, Chronic; Middle Aged; Myosins; Sorafenib; Myelodysplastic-Myeloproliferative Diseases; ETS Translocation Variant 6 Protein; 3. Good health; Repressor Proteins; 03 medical and health sciences; 0302 clinical medicine; fms-Like Tyrosine Kinase 3; Bone Marrow; Leukemia, Myeloid; Eosinophilia; Humans; Benzothiazoles

Genetic rearrangements involving FLT3 are rare and only recently have been detected in myeloid/lymphoid neoplasms associated with eosinophilia (MLN-eos) and chronic myeloproliferative disorders. Here we report two cases with FLT3 fusions in patients demonstrating mixed features of myelodysplastic/myeloproliferative neoplasms. In the first case, FLT3 was fused with a new fusion partner MYO18A in a patient with marrow features most consistent with atypical chronic myeloid leukemia; the second case involving ETV6-FLT3 fusion was observed in a case with bone marrow features most consistent with chronic myelomonocytic leukemia. Notably, we observed that samples from both patients demonstrated FLT3 inhibitor (quizartinib and sorafenib) sensitivity in ex vivo drug screening assay.