Effect of outpatient treatment of febrile neutropenia on the risk threshold for the use of CSF in patients with cancer treated with chemotherapy

Objectives: Febrile neutropenia (FN) in patients with cancer treated with chemotherapy has traditionally been managed with inpatient broad-spectrum antibiotics until the infection and neutropenia have resolved. A newer strategy is outpatient oral or intravenous antibiotics in selected patients after an initial hospitalization. We sought to determine these costs, both overall and relative to those of traditional management, and the optimal role of prophylactic colony-stimulating factor (CSF) in patients at greatest risk for FN. Methods: Existing economic decision models were modified by incorporating a treatment strategy for FN in which patients are classified as high- and low-risk according to criteria described by Talcott. Low-risk patients were assumed to be treated as outpatients. Overall costs with the revised economic model were assessed and sensitivity analyses were performed. Results: The costs of an episode of FN were estimated as 1) no CSF: $13,355; 2) CSF with hospitalization for FN: $8677; and 3) CSF with risk stratification and outpatient management in low-risk patients: $ 8188. The risk threshold for the cost-effective use of CSF was only slightly lower with outpatient treatment. When all patients with FN are treated as inpatients and the cost of hospitalization is $ 1750/day the risk threshold for FN at which prophylactic CSF becomes cost-effective is 16%. It is 15% when low-risk patients are treated as outpatients. Conclusions: Outpatient treatment slightly decreases the risk threshold for FN at which prophylactic CSF becomes cost-effective. The limited economic effect of this strategy may be because the patients who were at greatest risk of complications had significantly longer lengths of stay and accounted for most of the hospitalization costs.