Sorafenib as a Salvage Therapy in FLT3-ITD Negative Relapse/ Refractory Acute Myeloid Leukemia

Background: Multi-kinase inhibitor sorafenib showed dramatic effects in acute myeloid leukemia (AML) cells harboring fms-related tyrosine kinase 3-internal tandem duplication (FLT3-ITD) mutation. However, FLT3-ITD mutation only occurs in 25% of AML cases. The therapeutic effects of sorafenib in AML patients without FLT3-ITD are still in need of further investigation. Methods: A young AML patient with central nervous system (CNS) relapse was treated with sorafenib combined with chemotherapy. Another patient with refractory AML arising form chronic myelomonocytic leukemia (CMML) was treated with sorafenib monotherapy. Spinal and cranial magnetic resonance imaging (MRI), minimal residual disease (MRD) and peripheral blood cell count were monitored to evaluate disease status. Results: The patient with CNS relapse exhibited significant shrink of tumor volume. The other patient with refractory AML achieved hematological improvements. Conclusion: These two cases suggested that sorafenib might be utilized as a potent salvage therapy for some refractory/relapsed AML patients without the FLT3-ITD mutation.