Carbon ion radiation therapy for high-risk meningiomas

Background: We analyzed outcome after a carbon ion boost in combination with precision photon radiation therapy in patients with meningiomas. Patients and methods: Ten patients with meningiomas were treated with carbon ion RT as part of a Phase I/II trial. Carbon ion RT was conducted in conjunction with fractionated stereotactic RT (FSRT) or intensity-modulated RT (IMRT). Eight patients were treated as primary RT, in 2 patients carbon ion RT was performed as re-irradiation. Carbon ion RT was applied with a median dose of 18 Gy E, and photon RT was applied with a median dose of 50.4 Gy. Two patients with a history of former irradiation received 18 Gy E of carbon ion RT and a reduced dose of photon treatment. Results: The median follow-up time was 77 months. Five patients died during follow-up, of which four died of tumor progression. In the group treated in the primary situation, actuarial survival rates after RT were 75% and 63% at 5 and 7 years. After re-irradiation, both patients died at 10 and 67 months, respectively. Actuarial local control rates after primary RT were 86% and 72% at 5 and 7 years. Two patients developed tumor recurrence after re-irradiation, 6 and 67 months after treatment. Conclusion: In conclusion, carbon ion radiation shows promising results in patients with atypical or anaplastic meningiomas. Further evaluation in a larger, prospective study in comparison to proton RT or modern photon RT is needed to corroborate these results. (C) 2010 Elsevier Ireland Ltd. All rights reserved. Radiotherapy and Oncology 95 (2010) 54-59