Safety evaluation of outpatient ifosfamide regimens in adult sarcoma patients

Transitioning historically inpatient chemotherapy regimens to outpatient administration can reduce hospital stays, resource use, and healthcare expenditures while improving patient quality of life. However, agents like ifosfamide, commonly used in sarcoma, often necessitate inpatient administration for close monitoring of adverse effects. The Fred Hutchinson Cancer Center (FHCC) sarcoma group has developed criteria for outpatient ifosfamide administration after one successful inpatient administration. Nevertheless, there remains a paucity of literature characterizing the safety profile of outpatient ifosfamide administration.

This was a single-center, retrospective, observational study that included adults 18 years and older with a diagnosis of sarcoma receiving an ifosfamide-based regimen in the outpatient setting at FHCC between March 2021 and September 2024. The primary outcome was a composite proportion of grade 3 or higher ifosfamide-related neurotoxicity, hemorrhagic cystitis, febrile neutropenia, and uncontrolled nausea or vomiting. Secondary outcomes included days of hospitalization saved with outpatient administration.

A total of 12 patients met the inclusion criteria. The most common outpatient treatment regimen was AIM (42%) followed by IE (25%) and VDC-IE (25%). Out of a total of 53 outpatient cycles, 15 cycles (28.3%) across 4 patients (33.3%) had at least 1 grade 3 or higher adverse effect of interest included in the primary outcome. A total of 257 hospitalization days were saved with outpatient administration, resulting in an estimated cost savings of $987,651.

Overall, among sarcoma patients meeting the FHCC outpatient ifosfamide criteria, administration of ifosfamide in the outpatient setting is safe with considerable cost savings to the institution.