Background
Patients with breast cancer receiving chemotherapy have an increased risk of infection mediated through a low number of protective white blood cells (neutropenia). Neutropenia is a common toxicity of many chemotherapy agents and is caused by the suppression of the bone marrow. The first sign of infection is usually a fever,  which indicates a potentially life threatening condition if it occurs during severe neutropenia (febrile neutropenia). Febrile neutropenia requires hospital care including the administration of intravenous antibiotics and possible delays in the continuation of chemotherapy. Colony-stimulating factors are drugs administered during chemotherapy in order to prevent or reduce the incidence or duration of febrile neutropenia and neutropenia.

Key findings
?  Prophylactic treatment with colony-stimulating factors significantly reduces the risk of developing febrile neutropenia by 73%.
?  The estimated number of patients needed to be treated with colony-stimulating factors in order to prevent one event of febrile neutropenia is 12.
?  Although a significant decrease in all-cause mortality was noted, there was no reduction in infection-related mortality in patients on chemotherapy who received
colony-stimulating factor therapy.