CSF2 and myelophthisic anemia: Factors that have been studied that portend higher risk for the development of febrile neutropenia include but are not limited to age (65 or older), female sex, poor performance status based on medical comorbidities, as well as various disease-related and treatment-related predictors, such as myelophthisis, and failure to administer prophylactic granulocyte-macrophage colony-stimulating factor (GM-CSF) [4-8].