Introduction: Sodium fluorescein capability to accumulate in cerebral areas with blood-brain barrier damage makes it an ideal dye for intraoperative visualization of high-grade gliomas (HGG). A fluorescein-guided technique for HGG removal with a dedicated filter on the surgical microscope is presented (FLUOGLIO trial).

Methods: The FLUOGLIO study is a prospective phase II-trial to evaluate safety and obtain indications about efficacy of fluorescein-guided surgery for HGG. Until January 2015, 36 patients (mean age 62, range 40-74) were enrolled. Fluorescein was intravenous injected after intubation (5-10 mg/Kg). Tumor was removed with microsurgical technique and fluorescence visualization by BLU400 or YELLOW560 filters on the Pentero microscope (Carl Zeiss, Germany). Degree of tumor resection was calculated on an early (within 72 hours of surgery) postoperative MRI. In 13 patients, biopsies were performed at the tumor margin to evaluate sensitivity and specificity of fluorescein in tumor tissue identification.

Results: Median pre-operative tumor volume was 29.68 cm3 (1.3-87.8 cm3). No adverse reaction related to the administration of fluorescein was registered. Contrast-enhanced tumor was completely removed in 86% of the patients on early postoperative MRI (31/36). The remaining patients had a mean tumor resection of 92.1%. With a median follow-up of 12 months (mean follow-up 13,71 months), the 6 months PFS rate was 55.5% and median survival was 12 months (mean survival 13,71 months). Estimation of sensitivity and specificity of fluorescein in identifying tumor tissue was 81% and 79% respectively.

Conclusions: Fluorescein-guided technique with a dedicated filter on the surgical microscope is safe and allows a high-rate of complete resection of HGG at the early post-operative MRI.

Patient Care: Fluorescein-guided technique seems to allow a complete resection of HGG, thus hopefully extending 6 months PFS and OS.

Learning Objectives: By the conclusion of this session, participants should be able to: 1) Describe the importance of complete resection of HGG 2) Discuss about the different options of fluorescent-guided technique for HGG surgery 3) Know pros and cons of the fluorescein-guided technique for HGG removal

References: 1. Acerbi F, Broggi M, Eoli M, Anghileri E, Cuppini L, Pollo B, Schiariti M, Visintini S, Orsi C, Franzini A, Broggi G, Ferroli P. Fluorescein- guided surgery for grade IV gliomas with a dedicated filter on the surgical microscope: preliminary results in 12 cases. Acta Neurochir (Wien). 2013 Jul;155(7):1277-1286. 2. Acerbi F, Broggi M, Eoli M, Anghileri E, Cavallo C, Boffano C, Cordella R, Cuppini L, Pollo B, Schiariti M, Visintini S, Orsi C, La Corte E, Broggi G, Ferroli P. Is fluorescein-guided technique able to help in resction of high-grade gliomas? Neurosurg Focus. 2014 Feb;36(2); E5 3. Schebesch KM, Proescholdt M, Höhne J, Hohenberger C, Hansen E, Riemenschneider MJ, et al: Sodium fluorescein-guided resection under the YELLOW 560 nm surgical microscope filter in malignant brain tumor surgery—a feasibility study. Acta Neurochir (Wien) 155:693–699, 2013