The risk of febrile neutropenia increases with age and is influenced by comorbidities of the patient, the chemotherapeutic agents used, the number of previous lines of therapy, and the fields of prior radiotherapy.116 Depending upon the indication for chemotherapy, curative versus palliative, G-CSF prophylaxis may be considered to maintain dose intensity, but this rarely applies to patients with primary brain tumors. This evidence concerns the gene CSF3 and brain neoplasm.