This Journal feature begins with a case vignette highlighting a common clinical problem. Evidence supporting various strategies is then presented, followed by a review of formal guidelines, when they exist. The article ends with the authors' clinical recommendations. Colony-Stimulating Factors for Febrile Neutropenia during Cancer Therapy

A 55-year-old, previously healthy woman received a diagnosis of diffuse large-B-cell lymphoma after the evaluation of an enlarged left axillary lymph node obtained on biopsy. She had been asymptomatic except for the presence of enlarged axillary lymph nodes, which she had found while bathing. She was referred to an oncologist, who performed a staging evaluation. A complete blood count and test results for liver and renal function and serum lactate dehydrogenase were normal. Positronemission tomography and computed tomography (PET–CT) identified enlarged lymph nodes with abnormal uptake in the left axilla, mediastinum, and retroperitoneum. Results on bone marrow biopsy were normal. The patient’s oncologist recom mends treatment with six cycles of cyclophosphamide, doxorubicin, vincristine, and prednisone with rituximab (CHOP-R) at 21-day intervals. Is the administration of prophylactic granulocyte colony-stimulating factor (G-CSF) with the first cycle of chemotherapy indicated? T h e C l i nic a l Probl e m Cycling cells in the bone marrow are sensitive to some forms of chemotherapy, including DNA-damaging agents and agents that inhibit cell-cycle progression. Therefore, in patients who are treated with chemotherapy regimens that include such agents, normal hematopoietic cells undergo damage that is both immediate and cumulative. The most serious immediate consequence of chemotherapy is febrile neutropenia, which is defined as an absolute neutrophil count of less than 500 cells per cubic millimeter and a temperature of more than 38.5°C. Most stan dard-dose chemotherapy regimens are associated with 6 to 8 days of neutropenia. 1-3 Data from the National Cancer Institute (NCI) suggest that more than 60,000 patients are admitted for the treatment of febrile neutropenia annually, or approximately 8 cases per 1000 patients receiving cancer chemotherapy. 4 Febrile neutropenia predisposes patients to serious infections and even death, particularly if severe neutropenia persists for longer than 10 to 14 days. 4-6 In the study of NCI data, the in-hospital rate of death was 6.8%. 4 In another analysis, the overall in-hospital rate of death was 9.5% (and 15.3% for patients with documented infection). 6 The mean costs per hospitalization in these two studies were $13,372 and $19,110, respectively. 4,6