A case study of the clinical and economic impact of filgrastim in cancer patients in the home care setting is described. The risk of febrile neutropenia is greatly reduced when filgrastim therapy is begun prophylactically after a course of antineoplastic drug therapy. Such use of filgrastim may also reduce the need for hospitalization, prevent mucositis, and enable the next course of chemotherapy to be administered on schedule. Investigators at the University of New Mexico, noting studies showing merit in early hospital discharge of pediatric cancer patients with febrile neutropenia, decided to take the approach a step further by treatment febrile neutropenia entirely at home. Patients seen in the pediatric oncology clinic at the university hospital were considered candidates for home treatment if they had stable vital signs, were already receiving filgrastim after the completion of cancer chemotherapy, and lived within one hour of the hospital. Six cancer patients 2-17 years of age were studied between August 1992 and February 1994. These patients had 16 episodes of febrile neutropenia that were treated at home. The drug regimen consisted of prophylactic filgrastim (begun the day after completion of a course of antineoplastic therapy) and ceftazidime (when febrile neutropenia developed). None of the children were readmitted to the hospital. Infections resolved within 12 days in all cases. The total charge for treating the 16 episodes at home was $22,400 (drug charge for ceftazidime, visits by nurses, infusion-pump rental, and ancillary charges). The total charge for hospital treatment of these episodes would be $112,924 (bed charge and pharmacy charge). The difference suggests a potential savings of $90,524 from home care for this small group of patients. Treating febrile neutropenia in pediatric cancer patients at home is effective and cost-efficient if the patients are clinically stable and prophylactic filgrastim therapy has been started after the completion of cancer chemotherapy.