Fluorescence-guided resection of primary and recurrent malignant gliomas with 5-aminolevulinic acid. Preliminary results

Background and purpose: Extent of resection plays a key role in the treatment of malignant gliomas (MGs). Patients with complete glioma removal, followed by chemoradiation, obtain the longest overall and progression-free survival. Fluorescence-guided resection of MGs enables intraoperative visualization of glioma tissue and increases control of the resection. The authors present preliminary results of 5-aminolevulinic acid (5-ALA) application during the resection of primary and recurrent MGs. Material and methods: Six patients with either a suspected malignant glioma based on magnetic resonance imaging (MRI) or with recurrent glioblastoma multiforme were enrolled in the study. The extent of resection was calculated according to the postoperative MRI performed within 72 hours. Preoperative and early postoperative neurological status and Karnofsky Performance Scale (KPS) were compared. Results: Fluorescence of tumour tissue was observed in 5/6 patients (five with the histopathological diagnosis of glioblastoma multiforme and one with neurotoxoplasmosis and AIDS). Complete tumour resection was achieved in 5 patients. Postoperative KPS and neurological status deteriorated in 2 cases. Radiotherapy and chemotherapy did not interfere with the sensitivity of the fluorescence guided tumour visualization. Conclusions: Fluorescence-guided resection of primary and recurrent MGs with 5-ALA improves control of the tumour resection. It enables the cytoreduction to be maximized but experience in neuro-oncological surgery is required to avoid serious, postoperative neurological deficits.