Abstract
With the recent advances in technology, the role of radiation therapy is increasing in the treatment of benign brain tumors. In this article, charactristics and potentials of various high-technology radiotherapy modalities and machines are discussed. Gammaknife and cyberknife treatment can minimize irradiation to normal brain tissues, while tomotherapy and new linac-based image-guided radiotherapy (IGRT) machines can produce better dose distribution in the tumor. Nevertheless, all these modalities yield acceptable dose distribution for the treatment of benign brain tumors. One important issue in choosing a new radiation modality is the dose fractionation schedule.
Gammaknife treatment is usually completed in one fraction, while any fractionation schedule is available with tomotherapy and new linac-based IGRT machines. The optimal dose fractionation remains unclear for benign brain tumors, and future studies are expected to clarify the issue. Then, the optimal radiation modality would become clearer.
Using stereotactic irradiation or intensity-modulated radiation, long-term local control rates of over 90% have been reported for relatively small (<10 cm3) benign brain tumors (acoustic neuroma, craniopharyngioma, pituitary adenoma and meningioma). However, local control rates decrease with an increase in tumor size. Therefore, optimal radiation dose and fractionation schedule should be further investigated, especially for tumors with a large volume. In the future, stereotactic proton therapy and intensity-modulated proton therapy are expected to become popular, with the further development of particle therapy technologies.
