Fluorescence-guided resections of malignant gliomas--an overview

Radical resections of contrast-enhancing tumour in patients with malignant gliomas may be pertinent for survival but are often difficult to achieve due to uncertainties in distinguishing tumour margins intra-operatively. In this respect a number of novel methods are being examined which aim at enhancing resections. Among these methods, resections that exploit the accumulation of fluorescent porphyrins within malignant glioma tissue in response to exogenous administration of a metabolic percursor, 5-aminolevulinic acid, may offer particular advantages. This article summarises the clinical background and current status of 5-ALA drug development for fluorescence-guided resections of malignant gliomas and analyses the available literature with regard to possible mechanisms that govern the highly specific accumulation of fluorescent porphyrins in malignant glioma tissue in response to 5-ALA administration.