Is fluorescence-guided surgery with 5-ala in eloquent areas for malignant gliomas a reasonable and useful technique?

INTRODUCTION: High-grade gliomas surgery in eloquent areas must achieve two pivotal aims: oncological efficacy and preservation of unimpaired neurological functions or improvement of impaired neurological functions. Here, we evaluated the safety and the usefulness of 5-ALA fluorescence-guided surgery in eloquent areas.

MATERIAL AND METHODS: Single center, retrospective and consecutive series of adult patients operated on for a supratentorial glioblastoma between November 2012 and November 2015.

RESULTS: Fifty-one patients with a glioblastoma located within an eloquent area were included: 24 patients operated on with 5-ALA (5-ALA group), and 27 patients operated on under white light (control group). Preoperative motor and language deficits were similar in the 5-ALA group (50%, 37.5%) as in the control group (59.3%, 55.6%) (P=0.510; P=0.200). Three-month postoperative motor and language deficits rates were similar in the 5-ALA group (12.5%, 12.5%) as in the control group (29.6%, 14.8%) (P=0.180; P=0.990). The extent of resection did not significantly vary between groups (P=0.280). The overall survival did not significantly vary between groups (P=0.080) but the progression-free survival was significantly higher in the 5-ALA group than in the control group (P=0.020). The 12-month progression-free survival was significantly higher in 5-ALA group (60%) than in control group (21%; P=0.006). In multivariate analysis, the 5-ALA was an independent prognostic factor associated with progression-free survival (P=0.030).

CONCLUSION: 5-ALA fluorescence-guided surgery for glioblastoma located in eloquent areas is effective to improve progression-free survival. To preserve functional outcomes, it requires the routine use of intraoperative functional mapping to respect functional boundaries.