Resection of the contrast-enhancing tumor in diffuse gliomas bordering eloquent areas using electrophysiology and 5-ALA fluorescence: evaluation of resection rates and neurological outcome—a systematic review and meta-analysis

Abstract

Independently, both 5-aminolevulinic acid (5-ALA) and intraoperative neuromonitoring (IONM) have been shown to improve outcomes with high-grade gliomas (HGG). The interplay and overlap of both techniques are scarcely reported in the literature. We performed a systematic review and meta-analysis focusing on the concomitant use of 5-ALA and intraoperative mapping for HGG located within eloquent cortex. Using PRISMA guidelines, we reviewed articles published between May 2006 and December 2022 for patients with HGG in eloquent cortex who underwent microsurgical resection using intraoperative mapping and 5-ALA fluorescence guidance. Extent of resection was the primary outcome. The secondary outcome was new neurological deficit at day 1 after surgery and persistent at day 90 after surgery. Overall rate of complete resection of the enhancing tumor (CRET) was 73.3% (range: 61.9–84.8%, p < .001). Complete 5-ALA resection was performed in 62.4% (range: 28.1–96.7%, p < .001). Surgery was stopped due to mapping findings in 20.5% (range: 15.6–25.4%, p < .001). Neurological decline at day 1 after surgery was 29.2% (range: 9.8–48.5%, p = 0.003). Persistent neurological decline at day 90 after surgery was 4.6% (range: 0.4–8.7%, p = 0.03). Maximal safe resection guided by IONM and 5-ALA for high-grade gliomas in eloquent areas is achievable in a high percentage of cases (73.3% CRET and 62.4% complete 5-ALA resection). Persistent neurological decline at postoperative day 90 is as low as 4.6%. A balance between 5-ALA and IONM should be maintained for a better quality of life while maximizing oncological control.

Microsurgical resection of gliomas of the cingulate gyrus: a systematic review and meta-analysis

“…Such variations are explained by the different involved anatomical regions of the cingulate gyrus, as well as the extensions of gliomas in adjacent eloquent areas. Although neuronavigation, 5-ALA (in selected cases), and electrophysiology are important adjuncts in modern neurooncology, functional sparing by maximal safe resection is a core principle [ 11 ]. The anatomical cingulum segregation further explains the heterogenous symptoms and signs at initial presentation and also the potential postoperative deficit, including the most commonly reported SMA syndrome, with an overall rate of 18% (range 10–26%).…”

Automated online safety margin (GLIOVIS) for glioma surgery model

“…The clinical outcome of glioblastoma patients is poor with a median overall survival of approximately 15-18 months (1)(2)(3)(4). The extent of resection defined as the removal of the contrast-enhancing (CE) tumor is directly correlated with overall survival and progression-free survival (5)(6)(7)(8).…”