HYPOFRACTIONATED RADIOSURGERY FOR LARGE OR IN CRITICAL SITE INTRACRANIAL MENINGIOMA: RESULTS OF A PHASE II PROSPECTIVE STUDY
Mené entre 2011 et 2016 sur 178 patients atteints d'un méningiome intracrânien (durée médiane de suivi : 53 mois), cet essai de phase II évalue la sécurité, du point de vue des événements indésirables, d'une radiochirurgie hypofractionnée
Background: Radiosurgery is a well-known, safe and effective technique in the treatment of intracranial meningiomas. However, single fraction radiosurgery can lead to high rate of toxicity when large-volume or critically located lesions are targeted. Multisession, also called hypofractionated, radiosurgery (hypo-RS) might overcome these limitations. Accordingly, we carried out a prospective phase II trial, aiming to establish whether a fractionated-RS schedule of 25 Gy in 5 fractions would be safe and effective in treating large (≥ 3 cm) and/or critically located (less than 3 mm from critical structures) grade I intracranial meningiomas. Methods: We prospectively enrolled patients diagnosed with grade I meningiomas, large size and/or critically located lesions, either histologically diagnosed or imaging-defined; signed informed consent; age ≥ 18 years; Karnofsky Performance Status (KPS) ≥ 70. The main aim was to evaluate the safety of hypo-RS in terms of absence of adverse events (AEs). The secondary aim was to evaluate tumor response in terms of local control (LC), defined as stability or reduction of lesion volume. Results: Between 2011 and 2016, 178 patients were consecutively enrolled. The median follow-up was 53 months (range, 4-101 months). Overall, the toxicity rate was 12.7% (21/166 patients). At a minimum 5-year follow-up, the patient's toxicity rate was 11.7 % (9/77 patients). Symptom evaluation at both 3-year and last follow-up showed an improvement in most of the patients. Five-year local tumor control was 97% (95% confidence interval, CI, 92%-99%). Conclusions: hypo-RS schedule of 25Gy in 5 fractions is a well-tolerated option in the treatment of large-volume and/or critically located benign meningiomas. Early results suggest favorable local control, though longer term follow-up is required.
International Journal of Radiation Oncology, Biology, Physics 2022