Fluorescein Sodium-guided Resection of Glioblastoma Associated with Prolonged Survival: Retrospective Analysis from a Single-center

Introduction: Intraoperative fluorescence agents, including fluorescein-sodium (FS) and 5-aminolevulinic acid (5-ALA) have been shown to assist with surgical resection of glioblastoma multiforme (GBM). While 5-ALA is FDA-approved, FS is also used by neurosurgeons, and has shown comparable outcomes. In this study, we seek to provide additional evidence regarding the efficacy of FS in achieving gross total resection (GTR, ≥ 95% resection) and present the impact on the overall survival (OS) of patients.

Methods: We retrospectively identified patients with primary, solitary GBM that underwent tumor resection with or without FS-guidance (FSG) at our community hospital from 2010 through 2022. GTR or subtotal resection (STR) was determined based on surgeon and radiologist notes, and measurement of tumor diameters and volumes. A multivariate Cox regression was used to compare survival between both cohorts.

Results: 50 of the 57 patients identified in our analysis demonstrated IDH wild-type and unmethylated MGMT GBMs. 37 patients underwent FSG with 65% GTR (n = 24), 35% STR (n = 13). 20 patients underwent resection without the assistance of FSG with 55% GTR (n = 11) and 45% STR (n = 9). Baseline characteristics did not differ significantly among patients stratified by FS nor GTR. FSG was associated with a 12% greater incidence of survival, and with significantly prolonged survival, with an interaction hazard ratio (HR) of 0.13 (95% CI: 0.01 - 0.85, p = 0.034) with GTR. GTR was associated with an insignificantly greater overall survival among all patients (273 days (STR) versus 533 days (GTR), p = 0.142).

Conclusion : We present a preliminary retrospective analysis of patients with GBM who underwent FS-guided resection at our institution. The findings of this study are restricted by limited sample size and inclusion of only primary resections of GBM. This suggests the need for further investigation regarding the utility of FS on surgical resection.