P14.01.B 5-ALA FLUORESCENCE-GUIDED SURGERY VERSUS WHITE-LIGHT CONVENTIONAL MICROSURGERY FOR THE RESECTION OF NEWLY-DIAGNOSED GLIOBLASTOMAS (RESECT STUDY): A FRENCH MULTICENTER RANDOMIZED PHASE-III STUDY
Authors: Picart T , Pallud J , Berthiller J , Dumot C , Berhouma M , Ducray F , Armoiry X , Margier J , Guerre P , Varlet P , Meyronet D , Metellus P , Guyotat J ,   RESECT Study group
Published: October 2024

Abstract

BACKGROUND
The performances of 5-ALA-fluorescence-guided surgery for glioblastoma resection have been assessed by only one phase-III prospective randomized study, published in 2006. The aim of the RESECT study was to compare the onco-functional results associated to 5-ALA-fluorescence and to white-light conventional microsurgery in glioblastoma patients managed according to the current standards of cares.

MATERIAL AND METHODS
This phase-III prospective randomized single-blinded study involved 21 French neurosurgical centers and compared 5-ALA-fluorescence-guided resection with white-light conventional microsurgery in glioblastoma patients managed according to the current standards of cares, including neuronavigation use and post-operative radio-chemotherapy. 5-ALA (20 mg/kg) or placebo (ascorbic acid) were administered orally 3 to 5 hours before the incision. An independent committee blindly assessed the rate of Gross Total Resection (GTR) as a primary endpoint. (ClinicalTrials.gov Identifier: NCT01811121).

RESULTS
Between March 2013 and August 2016, a total of 171 patients were assigned to the 5-ALA-fluorescence group (n=88) or to the placebo group (n=83). Twenty-four patients were excluded because the WHO histological criteria of grade 4 glioma were not met. The proportion of GTR was significantly higher in the 5-ALA-fluorescence group (53/67, 76.8%) than in the placebo group (33/69, 47.8%; p=0.0002). After adjustment on age, preoperative KPS score, and tumor location, GTR was still associated with 5-ALA-fluorescence (OR [95%CI]: 4.13 [1.94;8.79]). The mean 7-day postoperative KPS score (≥80% in 49/71, 69.0% 5-ALA; 50/71, 70.4% placebo, p=0.86) and the proportion of patients with a worsened neurological status 3 months postoperatively (9/68, 13.2% 5-ALA; 9/70, 12.9% placebo, p=0.95) did not differ. Adverse events related to 5-ALA intake were rare and consisted of photosensitization in 4/87 (4.6%) patients and hepatic cytolysis in 1/87 (1.1%) patients. The 6-month PFS (70.2 [57.7;79.6]% and 68.4 [55.7;78.1]%; p=0.39) and 24-month OS (30.1 [18.9;42.0]% and 37.7 [25.8;49.5]%; p=0.89) did not differ. In multivariate analysis, GTR was an independent predictor of PFS (HR=0.56 [0.36;0.86], p=0.008) and OS (HR=0.65 [0.42; 1.01], p=0.05). 5-ALA-fluorescence-guided surgery generated a significant extra-cost of 2732.36€, 95%CI [1658.40;3794.11].

CONCLUSION
The quality of glioblastoma resection remains a strong predictor of survival. 5-ALA-fluorescence-guided surgery is cost-effective and safely optimizes the extent of resection in patients harboring glioblastoma amenable to large resection.

FUNDING
The RESECT study was founded by a grant from the Directorate of Health Care Supply (DGOS, Direction Générale, de l’Offre de Soins) of the French ministry of health via the program for innovative and costly techniques