5-Aminolevulinic Acid False-Positive Rates in Newly Diagnosed and Recurrent Glioblastoma: Do Pseudoprogression and Radionecrosis Play a Role? A Meta-Analysis

• Published in: Frontiers in oncology Vol. 12; p. 848036
• Main Authors: Ricciardi, Luca, Sturiale, Carmelo Lucio, Scerrati, Alba, Stifano, Vito, Somma, Teresa, Ius, Tamara, Trungu, Sokol, Acqui, Michele, Raco, Antonino, Miscusi, Massimo, Della Pepa, Giuseppe Maria
• Format: Journal Article
• Language: English
• Published: Switzerland Frontiers Media S.A 17.02.2022
• Subjects: 5-ALA fluorescence; glioblastoma; high-grade glioma (HGG); Oncology; pseudoprogression; radionecrosis; recurrent glioblastoma; pseudoprogression; recurrent glioblastoma; high-grade glioma (HGG); 5-ALA fluorescence; glioblastoma; radionecrosis
• ISSN: 2234-943X; 2234-943X
• DOI: 10.3389/fonc.2022.848036

Several studies have confirmed the impact of 5-aminolevulinic acid (5-ALA) on the extent of resection in newly diagnosed glioblastoma (GBM). However, there are controversies on the 5-ALA fluorescence status in recurrent GBM surgery, with specific reference to pseudoprogression or radionecrosis; therefore, the safety and accuracy of surgical planning in 5-ALA-assisted procedures in the recurrent context are still unclear. This is a systematic review and meta-analysis of comparative studies on the use of 5-ALA in newly diagnosed and recurrent GBM, consistently conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. Data on fluorescence status and correlation between fluorescence and histological findings were collected. We performed a meta-analysis of proportions to estimate the pooled rates of each outcome. Three online medical databases (PubMed, Scopus, Cochrane Library) were screened, 448 articles were evaluated, and 3 papers were finally included for data analysis. Fluorescence rate was not different between newly diagnosed and recurrent GBM [p = 0.45; odds ratio (OR): 1.23; 95% CI: 0.72-2.09; I = 0%], while the rate of 5-ALA fluorescence-positive areas not associated with histological findings of GBM cells was higher in recurrent GBM (p = 0.04; OR: 0.24; 95% CI: 0.06-0.91; I = 19%). Furthermore, there were no cases of radionecrosis in false-positive samples, while inflammation and signs of pseudoprogression were found in 81.4% of the cases. Therefore, a robust awareness of 5-ALA potentialities and pitfalls in recurrent GBM surgery should be considered for a cognizant surgical strategy. Further clinical trials could confirm the results of the present meta-analysis.