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

Objective Meningiomas are the second most common tumors in neurofibromatosis type 2 (NF-2). Microsurgery is challenging in NF-2 patients presenting with skull base meningiomas due to the intrinsic risks and need for multiple interventions over time. We analyzed treatment outcomes and complications after primary Gamma Knife radiosurgery (GKRS) to delineate its role in the management of these tumors. Methods An international multicenter retrospective study approved by the International Radiosurgery Research Foundation was performed. NF-2 patients with at least one growing and/or symptomatic skull base meningioma and 6-month follow-up after primary GKRS were included. Clinical and radiosurgical parameters were recorded for analysis. Results In total, 22 NF-2 patients with 54 skull base meningiomas receiving GKRS as primary treatment met inclusion criteria. Median age at GKRS was 38 years (10-79 years). Most lesions were located in the posterior fossa (55.6%). Actuarial progression free survival (PFS) rates were 98.1% at 2 years and 90.0% at 5 and 10 years. The median follow-up time after initial GKRS was 5.0 years (0.6-25.5 years). Tumor volume at GKRS was a predictor of tumor control. Lesions >5.5 cc presented higher chances to progress after radiosurgery ( p = 0.043). Three patients (13.64%) developed adverse radiation effects. No malignant transformation or death due to meningioma or radiosurgery was reported. Conclusions GKRS is effective and safe in the management of skull base meningiomas in NF-2 patients. Tumor volume deserve greater relevance during clinical decision-making regarding the most appropriate time to treat. GKRS offers a minimally invasive approach of particular interest in this specific group of patients.

• Klíčová slova
• gamma knife radiosurgery, meningioma, neurofibromatosis type 2, skull base,
• 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

PURPOSE: We reviewed the survival time for patients with primary brain tumors undergoing treatment with stereotactic radiation methods at the Masaryk Memorial Cancer Institute Brno. We also identified risk factors and characteristics, and described their influence on survival time. METHODS: In summarizing survival data, there are two functions of principal interest, namely, the survival function and the hazard function. In practice, both of them can depend on some characteristics. We focused on nonparametric methods, propose a method based on kernel smoothing, and compared our estimates with the results of the Cox regression model. The hazard function is conditional to age and gross tumor volume and visualized as a color-coded surface. A multivariate Cox model was also designed. RESULTS: There were 88 patients with primary brain cancer, treated with stereotactic radiation. The median survival of our patient cohort was 47.8 months. The estimate of the hazard function has two peaks (about 10 months and about 40 months). The survival time of patients was significantly different for various diagnoses (p≪0.001), KI (p = 0.047) and stereotactic methods (p = 0.033). Patients with a greater GTV had higher risk of death. The suitable threshold for GTV is 20 cm3. Younger patients with a survival time of about 50 months had a higher risk of death. In the multivariate Cox regression model, the selected variables were age, GTV, sex, diagnosis, KI, location, and some of their interactions. CONCLUSION: Kernel methods give us the possibility to evaluate continuous risk variables and based on the results offer risk-prone patients a different treatment, and can be useful for verifying assumptions of the Cox model or for finding thresholds of continuous variables.

• MeSH
• dospělí MeSH
• Kaplanův-Meierův odhad MeSH
• lidé středního věku MeSH
• lidé MeSH
• meningeom mortalita   patologie   chirurgie   MeSH
• mladiství MeSH
• mladý dospělý MeSH
• nádory mozku mortalita   patologie   chirurgie   MeSH
• prognóza MeSH
• proporcionální rizikové modely MeSH
• radiochirurgie MeSH
• senioři nad 80 let MeSH
• senioři MeSH
• tumor burden 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
• práce podpořená grantem MeSH
• srovnávací studie MeSH