289P - Low risk febrile neutropenia: Does combined chemotherapy/immune checkpoint inhibitor necessitate a change in approach?

Background

Management of patients with low-risk febrile neutropenia (LRFN) in an outpatient setting guided by the MASCC score is proven to be safe and effective. The addition of ICI therapy has revolutionised the management of early triple-negative breast cancer (TNBC) but its effects on acuity of emergency presentations remains unknown. We examined the clinical severity of FN in patients treated with PC-EC in the neoadjuvant setting.

Methods

An observational analysis was performed at a specialist oncology hospital in England. In 2017, the hospital established an ambulatory pathway for the management of LRFN. We analysed prospectively collected databases for patients presenting with febrile neutropenia in 2017 and 2022 extracting triple negative patients treated neoadjuvantly with PC-EC. We compared this to patients presenting with FN following treatment with PC-EC/Pembrolizumab since December 2022 up until April 2024.

Results

In the study periods, 152 patients received PC-EC and 151 PC-EC/Pembro. There were significant more emergency attendances in the PC-EC/Pembro cohort (132 vs 53). Twenty-five patients presented with FN in the PC-EC/Pembro group and 16 in those receiving PC-EC (16% vs 11%, p>0.05). The patients in the PC-EC/Pembro cohort were older (median age 52 vs 45; p=0.04). Patients with febrile neutropenia treated with PC-EC/Pembro had more severe clinical presentations (MASCC = 18 vs 24; p=0.01), worse physiological parameters (NEWS2 at presentation 3 vs 2; p=0.0.23) and had a longer length of hospital stay (median 5 days vs 0 days; p = 0.044). There were no deaths at 30 or 90 days. Two patients in the PC-EC/Pembro group required organ support in ICU for management of neutropenic sepsis. One patient in the PC-EC group required ICU monitoring following thrombolysis for a massive PE with concomitant FN.

Conclusions

This analysis suggests that amongst patients treated with PC-EC/Pembro FN presentations are more severe resulting in longer lengths of stay. This has potential implications for the acute care resources required to manage patients in this cohort both in terms of emergency oncology and intensive care services. This may necessitate greater caution in pathways for ambulatory management for this cohort.

Clinical trial identification

Editorial acknowledgement

Legal entity responsible for the study

The authors.

Funding

Has not received any funding.

Disclosure

A. Lewis: Financial Interests, Personal, Speaker’s Bureau: Novartis, Servier, BMS; Financial Interests, Personal, Other, Educational material development: Novartis. A.C. Armstronh: Financial Interests, Institutional, Research Funding: AstraZeneca; Financial Interests, Personal, Other, travel and conference support: Novartis; Financial Interests, Personal, Other, Conference fees: MSD; Financial Interests, Personal, Advisory Board: AstraZeneca, Roche. All other authors have declared no conflicts of interest.