The purpose of this study is to compare any good and bad effects of using radiation to treat a meningioma that has been completely removed compared with the more common approach of observing the tumor and treating it with radiation if it returns. Using radiation before the tumor returns could prevent it from returning but it could also cause side effects. This study will allow the researchers to know whether this usual approach (treating you with radiation) is better, the same, or worse than the other usual approach (observation after surgery). Surgery alone has resulted in tumor control of about 50% to 75% and 3 to 5 years. We will be looking carefully at the 3-year results, and expect surgery with complete removal alone to control a WHO grade II meningioma in around 70% of patients at that interval. To be better, the use of radiation after surgery and before the tumor returns should improve the likelihood that the tumor does not grow back by at least 15% at 3 years, as compared to the surgery alone.
There will be about 148 people taking part in this study.