Neoplastic transformation after radiosurgery or radiotherapy: risk and realities.

In recent years, the use of radiosurgery or radiotherapy for benign brain tumors has increased significantly. Although long-term follow-up from several centers suggests that radiosurgery or radiotherapy is effective and safe, there are particular concerns regarding development of radiation-induced tumors. This article reviews the use of radiosurgery and fractionated radiation therapy with particular regard to new tumor induction and malignant transformation. The authors have found that the risk of radiation associated tumors after radiosurgery or radiotherapy for benign brain tumors is very low. All patients should be informed about the risks and consequences of radiation and microsurgery. The current practice standards for radiosurgery should not be modified because of this very low risk.