Efficacy of external fractionated radiation therapy in the treatment of meningiomas: a 20-year experience

Background: This is a retrospective analysis of a series of meningiomas tre ated by radiotherapy. Materials and methods: From 1978 to 1997, 45 patients with intracranial men ingiomas were referred for external fractionated radiotherapy at Centre Ale xis Vautrin. All patients were given 50-70 Gy to the tumor bed (median: 56 Gy) 1.8-2 Gy per fraction. Results: Evaluation was performed in June 1999 using the Kaplan-Meyer actua rial method with a median follow-up of 30 months (range: 1-166), relapse-fr ee survivals (RFSs) were 75% at 5 years and 67% at 8 years; overall surviva l (OS) was 74% at 5 and 8 years. For the 26 benign histologically documente d lesions, RFSs were 95% at 5 years and 81% at 8 years; OS was 85% at 5 and 8 years. One major radiation-induced complication occurred in this series (decline of cognitive function). According to the indication of radiotherap y, we divided the series into four groups: postoperative irradiation after a first subtotal resection (11 patients), 5-year RFS was 90%; after first r ecurrence (+/- salvage surgery, 14 patients), 73%; after further recurrence ( +/- salvage surgery, 11 patients), 67%; as exclusive treatment (nine pat ients), 80%. Atypical and malignant lesions (n = 7) all relapsed before 24 months of follow-up, all patients but one died before 42 months. Age at the time of irradiation (greater than or equal to 60 vs. <60 years) and radiot herapy dose (<greater than or equal to>60 vs. <60 Gy) did not influence loc al control or OS. Atypical and malignant lesions (WHO grades II and III) me ningiomas had a worse outcome than benign lesions (WHO grade I, P < 0.01). Conclusions: These results compare favorably with previously published data . External fractionated radiotherapy is well tolerated and effective. There is still a debate about the place of radiotherapy in the treatment of meni ngiomas: after subtotal resection, should radiotherapy be given postoperati vely or at the time of progression? Should radiotherapy replace surgery whe n the risk of postoperative sequellae is high? Prospective randomized trial s Would be required to address these issues. ((C) 2001 Elsevier Science h-e land Ltd. All rights reserved.