Fluorescein-guided surgery for the resection of pilocytic astrocytomas: A multicentric retrospective study

Abstract

ObjectivePilocytic astrocytomas (PAs) are relatively benign tumors, usually enhancing on post-contrast MRI and often characterized by a mural nodule within a cystic component. Surgical resection represents the mainstay of treatment, and extent of resection (EOR) is associated with improved survival. In this study, we analyzed the effect of sodium fluorescein (SF) on the visualization and resection of these circumscribed astrocytic gliomas.MethodsSurgical databases at two neurosurgical departments (Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy and Department of Neurosurgery, University Medical Center Regensburg, Regensburg, Germany) were retrospectively reviewed to identify the cohort of patients with pilocytic astrocytoma who had undergone fluorescein-guided tumor resection at any of the centers between March 2016 and February 2022. SF was intravenously injected (5 mg/kg) immediately after the induction of general anesthesia. Tumors were removed using a microsurgical technique with the YELLOW 560 filter (Carl Zeiss Meditec, Oberkochen, Germany).ResultsForty-four patients (25 males and 19 females; 26 pediatric patients, mean age of 9.77 years, range 2 to 17 years; and 18 adult patients, mean age of 34.39 years, range 18 to 58 years) underwent fluorescein-guided surgery. No side effects related to SF occurred. In all tumors, contrast enhancement on preoperative MRI was correlated with intense, heterogeneous yellow fluorescence with bright fluorescent cystic fluid. Fluorescein was considered helpful in distinguishing tumors from viable tissue in all cases except three patients due to faint fluorescein enhancement. Biopsy was intended in two operations, and partial resection was intended in three operations. Gross total resection was achieved in 24 cases out of 39 patients scheduled for tumor removal (61.54%), in five cases a minimal residual volume was highlighted by postoperative MRI despite the intraoperative subjective evaluation of complete tumor removal (12.82%); in the other 10 cases, the resection was subtotal with fluorescent residual spots to avoid neurological worsening (25.64%).ConclusionsThe use of SF is a valuable method for safe fluorescence-guided tumor resection. Our data showed a positive effect of fluorescein-guided surgery on intraoperative visualization during resection of Pas, suggesting a possible role in improving the extent of resection of these lesions.

Fluorescein sodium in the surgical treatment of pleomorphic xanthoastrocytomas: Results from a retrospective study

“…During the last years SF has emerged as intraoperative tracer able to improve brain-tumor visualization ( 14 – 16 ), due to its vascular, non-specific mechanism of action related to the accumulation in brain regions with BBB disruption ( 9 , 12 ): these areas present an altered permeability that seems to correlate consistently with the contrast enhanced portions of T1-weighted MRI sequences, accounting for the staining capacity of this fluorescent tracer with tumors that uptake contrast ( 21 ). Previous experiences had suggested that the use of SF could be associated with a bright fluorescence of the tumor area in primary and recurrent high-grade gliomas ( 14 , 15 , 20 , 29 ), in brain metastases ( 17 ), in primary CNS lymphomas ( 18 ), in gangliogliomas ( 16 ), and recently in the similar entity of circumscribed astrocytic gliomas which are the pilocytic astrocytomas ( 30 ): this was also associated with good results in term of extent of resection as well as PFS and OS. In particular, in the heterogeneous group of PA, a maximal safe resection was reached in more than 80% of cases.…”

The role of sodium fluorescein in pediatric supratentorial intra-axial tumor resection: new insights from a monocentric series of 33 consecutive patients

“…Additionally, the recent availability of an integrated and speci c lters in the surgical microscope has contributed to the wide diffusion of uorescein [14][15][16]. Previous experiences suggested that the use SF could be associated with a bright uorescence of the tumor area in HGG [20], in metastases [27], in gangliogliomas [28], in pilocytic astrocytomas [29] and in spinal intramedullary lesions [30]. This was also associated with good results in term of extent of resection as well as progression free and overall survival.…”

Sodium fluorescein in pediatric oncological neurosurgery: a pilot study on 50 children

“…4). The role of SF in low-grade tumors is still debated in the literature, although a progressive number of series are reporting positive results in these groups [19], [21]. SF appears as one amongst several new tools, like intraoperative imaging and monitoring, helping to enhance the accuracy of tumor resection.…”

“…extravasation [14]. Its role in high-grade gliomas (HGG) has been repeatedly suggested [15], but some literature articles also reported its use in other malignant or benign conditions [16]- [21], as well as in exclusively pediatric populations [22], [23], generally without any type of adverse reaction. However, a de nitive statement about feasibility and utility of SF in pediatrics has not been formulated yet.…”