BACKGROUND AND PURPOSE: Radiotherapy (RT) may be a safe alternative to surgery for selected intracranial meningiomas, particularly in eloquent or high-risk surgical locations. Reported studies of stereotactic RT have utilized stereotactic radiosurgery (SRS), fractionated stereotactic radiotherapy (hFSRT), or conventional radiotherapy. This retrospective study aimed to compare toxicity in a large international cohort. MATERIALS AND METHODS: A total of 473 consecutive patients were treated for intracranial meningioma at two radiation oncology clinics. The patients underwent various treatment modalities, including stereotactic radiosurgery (SRS), hypofractionated stereotactic radiotherapy (hFSRT, 2-5 fractions), or normofractionated stereotactic radiotherapy (nFSRT, 28-30 fractions) using CT-linac or Cyberknife radiation techniques. The evaluation of potential brain edema and radiation necrosis (RN) was conducted using magnetic resonance imaging (MRI). RESULTS: Radiation-induced brain edema occurred in 11.0% of patients, including 4.9% with symptomatic edema requiring corticosteroid therapy, and 4.0% of patients developed radiation necrosis. Despite a smaller irradiated tumor volume, the risk of radiation-related toxicity was higher with SRS compared to hFSRT and nFSRT, for both brain edema (hazard ratio [HR] = 4.10, 95% confidence interval (CI; 2.02; 8.26), p < 0.001) and RN (HR = 11.07, 95% CI (2.65; 46.24), p < 0.001). Cox regression showed a 33 and 28% increased risk of brain edema and RN per 1 cm3 of tumor volume (HR = 1.33, 95% CI (1.21; 1.46), p < 0.001 and HR = 1.28, 95% CI (1.13; 1.46), p < 0.001). For tumor volumes above the median (2.05 cm3), the risk of toxicity following SRS was significantly higher for edema (HR = 9.70, 95% CI (2.90; 32.40), p < 0.001) and RN (HR = 13.34, 95% CI (1.73; 102.80), p = 0.013). CONCLUSION: Stereotactic radiotherapy and radiosurgery are safe treatment options for intracranial meningiomas. However, our data indicate a significantly increased risk of radiation necrosis and edema after SRS for tumors larger than 2 cm3 (diameter > 1.55 cm). This study also highlights the safety of both nFSRT and hFSRT in the treatment of larger tumors, supporting treatment selection based on tumor volume.

• Klíčová slova
• Brain tumor, Cyberknife, Meningioma, Radiation necrosis, Radionecrosis, Radiosurgery,
• Publikační typ
• časopisecké články MeSH

BACKGROUND: Stereotactic radiosurgery (SRS) is increasingly used for management of perioptic meningiomas. OBJECTIVE: To study the safety and effectiveness of SRS for perioptic meningiomas. METHODS: From 12 institutions participating in the International Radiosurgery Research Foundation (IRRF), we retrospectively assessed treatment parameters and outcomes following SRS for meningiomas located within 3 mm of the optic apparatus. RESULTS: A total of 438 patients (median age 51 yr) underwent SRS for histologically confirmed (29%) or radiologically suspected (71%) perioptic meningiomas. Median treatment volume was 8.01 cm3. Median prescription dose was 12 Gy, and median dose to the optic apparatus was 8.50 Gy. A total of 405 patients (93%) underwent single-fraction SRS and 33 patients (7%) underwent hypofractionated SRS. During median imaging follow-up of 55.6 mo (range: 3.15-239 mo), 33 (8%) patients experienced tumor progression. Actuarial 5-yr and 10-yr progression-free survival was 96% and 89%, respectively. Prescription dose of ≥12 Gy (HR: 0.310; 95% CI [0.141-0.679], P = .003) and single-fraction SRS (HR: 0.078; 95% CI [0.016-0.395], P = .002) were associated with improved tumor control. A total of 31 (10%) patients experienced visual decline, with actuarial 5-yr and 10-yr post-SRS visual decline rates of 9% and 21%, respectively. Maximum dose to the optic apparatus ≥10 Gy (HR = 2.370; 95% CI [1.086-5.172], P = .03) and tumor progression (HR = 4.340; 95% CI [2.070-9.097], P < .001) were independent predictors of post-SRS visual decline. CONCLUSION: SRS provides durable tumor control and quite acceptable rates of vision preservation in perioptic meningiomas. Margin dose of ≥12 Gy is associated with improved tumor control, while a dose to the optic apparatus of ≥10 Gy and tumor progression are associated with post-SRS visual decline.

• Klíčová slova
• Gamma Knife, Outcomes, Perioptic meningioma, Progression-free survival, Stereotactic radiosurgery, Visual outcomes,
• MeSH
• doba přežití bez progrese choroby MeSH
• dospělí MeSH
• internacionalita * MeSH
• lidé středního věku MeSH
• lidé MeSH
• magnetická rezonanční tomografie metody   MeSH
• meningeální nádory diagnóza   chirurgie   MeSH
• meningeom diagnóza   chirurgie   MeSH
• mladiství MeSH
• mladý dospělý MeSH
• následné studie MeSH
• nervus opticus chirurgie   MeSH
• radiochirurgie metody   MeSH
• retrospektivní studie MeSH
• senioři nad 80 let MeSH
• senioři MeSH
• výsledek terapie MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladiství MeSH
• mladý dospělý MeSH
• mužské pohlaví MeSH
• senioři nad 80 let MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• multicentrická studie MeSH