5-Aminolevulinic acid fluorescence guided surgery for recurrent high-grade gliomas

Muhammad Omar Chohan, Mitchel S. Berger

Fluorescence guided surgery (FGS) with five-aminolevulinic acid (5-ALA) is expected to revolutionize neurosurgical care of patients with high-grade gliomas (HGG). After the recent landmark FDA approval, this optical agent is now available to neurosurgeons in the United States. This review is designed to highlight the evidence for the use of 5-ALA in recurrent HGG surgery for the neurosurgical community. The manuscript was prepared in accordance with the PRISMA guidelines. Intra-operatively, a strong fluorescent signal is highly correlated with the presence of cellular tumor in recurrent HGG, giving it a high positive predictive value (PPV). Similar to what is observed in primary HGG surgery, false-negative results can occur if tumor cells do not emit fluorescence. In addition, false-positive fluorescence signals in tissues devoid of tumor cells can be observed more frequently in recurrent HGG compared to the primary setting. However, these areas overwhelmingly contain reactive/regressive tissue, resection of which is unlikely to cause functional deficits. The safety profile of 5-ALA is similarly favorable in primary and recurrent HGG. 5-ALA FGS is a powerful adjunct in the resection of recurrent HGG with a high PPV and favorable safety profile. It is therefore the authors' opinion to routinely employ this fluorescent agent as a standard of care.