Abstract
INTRODUCTION: It is well appreciated that maximal resection of glioblastomas improves outcome but is difficult to achieve due to the invasive nature of gliomas. 5-aminolevulinic acid (5-ALA) improves tumour detection by selective conversion to a fluorophore in tumour tissue that is detected by fluorescence under blue light. This meta-analysis aims to assess the ability of 5-ALA as a tool for identifying tumour as well as the efficacy, safety and cost-effectiveness of 5-ALA resections. METHOD: A systematic review of PubMed and EMBASE was was supplemented with review of the trials registry and expert opinion. Case reports and reviews were excluded. Studies reporting diagnostic accuracy, clinical efficacy (extent of resection or progression free survival [PFS]), safety or cost effectiveness in adults with resected high grade gliomas were included. RESULTS: 52 studies were identified of which 21 fulfilled the search criteria. The diagnostic accuracy of fluorescence identifying tumour had 87% sensitivity, 93% specificity, 98% positive predictive value and 58% negative predictive value. 72.3% of patients had a complete resection of the enhancing tumour. Two studies demonstrated a prolonged PFS compared to a white light group. There were no increases in morbidity in patients without deficits pre-operatively. 5-ALA costs £1,241.56 more per patient and this is largely due to patients receiving more cycles of chemotherapy. The cost per QALY was £7,424.46 - well below the NICE threshold. CONCLUSION: This meta-analysis shows that 5-ALA is an accurate diagnostic tool, improves progression free survival but does not increase morbidity and is cost effective. This should now be considered as a standard of care.