Role of 5-ALA in improving extent of tumour resection in patients with Glioblastoma Multiforme.

Goal of surgery for patients with Glioblastoma Multiforme (GBM) is gross total resection with no new neurological deficits. Surgical resection is often restricted due the difficulty in differentiating the tumour from surrounding normal brain using either naked eye, or standard intra-operative white light microscopy. GBM uptakes orally administered 5-ALA becomes fluorescent when viewed by a special light, and this property has been used to improve intra-operative tumour identification. This technique should therefore allow better extent of tumour resection. The hypothesis has been tested through several studies and even though most studies are of low quality, they strongly favour the use of 5- ALA in improving the extent of resection when compared to white light microscopy. A systematic review on the topic had a similar conclusion. Few studies have also hinted on a high false negative rate with the use of this technique..