Turkish Neurosurgery
Could Fluorescein Staining in Low Grade Glial Tumors Guide for Peroperative Differentiation of Pathological Types?
Mahmut Ozden1, Orkhan Mammadkhanli2, Murat Zaimoğlu3, Eyüp Bayatlı4, Melih Bozkurt5
1Memorial Hospital, Neurosurgery, Istanbul,
2Trakya University, Neurosurgery, Edirne,
3Ankara University, Neurosurgery, Ankara,
4Ankara University, Neurosurgery, Ankara,
5Arel University, Neurosurgery, Istanbul,
DOI: 10.5137/1019-5149.JTN.42622-22.2

Aim:To enhance survival rates, the peroperative distinction of low-grade glioma subtypes (LGGs) is important in providing gross total resection. Especially if the pathological tumour diagnosis is diffuse astrocytoma or pre-glioblastoma, the prognostic contribution of gross total resection is direct. Nonetheless, the methods to understand the lesion types are limited, and it is impossible to distinguish the subtypes of LGGs with direct intraoperative vision. One of the potential tools may be fluorescein staining, yet the efficacy of fluorescein in determining LGG tumour borders is not clear yet. In this study, we aimed to define the characteristics of fluorescein staining in 3 different subtypes of WHO Grade-2 gliomas. Material and Methods:We studied 46 patients with supratentorial newly diagnosed non-contrast enhancing LGGs removed by fluorescent guidance under the YELLOW 560 nm filter. Patients between July 2019 and 2022 were retrospectively analysed. Clinical data were collected from patient records. Patients’ intraoperative video recordings, pathological examination and preoperative magnetic resonance imaging (MRI) were analysed and compared for each patient after the operation. Histopathologically, patients were divided into WHO Grade-2 oligodendrogliomas, diffuse astrocytomas (IDH mutant, 1p19q negative tumours) and pre-glioblastomas (IDH wild type, 1p19q negative tumours). Resection margins were checked by using control contrast-enhanced cranial MRI at the postoperative 24-72 hours. Results:Our observations indicate that fluorescein primarily stains diffuse astrocytomas (IDH mutant, 1p19q negative tumours) and pre-glioblastomas (IDH wild type, 1p19q negative tumours) rather than WHO Grade-2 oligodendrogliomas. Conclusion:Fluorescein staining might be an option to determine tumour borders in WHO Grade-2 glial tumours, especially for those with a higher malignancy potential.

Corresponding author : Melih Bozkurt