The purpose of this study is to determine the best radiation dose for participants with meningioma that has grown back after previous surgery, or which the surgeon has been unable to remove completely. This research study is designed to determine whether a higher dose of radiation will decrease the likelihood that the tumor will grow back, compared to the probability of re-growth that occurs after standard radiation doses.

• After initial interview and physical examination, an immobilization device (head mask, neck support, back support, etc.) will be made for the participant. A treatment planning CT will be performed and a radiation treatment plan will be based on this CT scan.
• The radiation dose will usually be given once a day, five days per week. The radiation treatment will take between 7 and 8 1/2 weeks, including treatment planning.
• Treatment doses will vary, and the dose each participant will receive will be made on the basis of random assignment. Participants will either receive the usual dose of 55.8 CGE in 31 treatments or 1.8 CGE, or 63 CGE in 35 treatments of 1.8 CGE.

Inclusion Criteria:

• Age 18 or over
• Histological documentation of benign meningioma
• Documentation by imaging studies (CT and/ or MRI) or residual or recurrent intracranial tumor
• Karnofsky performance status of ≥ 70
• Study specific informed consent

Exclusion Criteria:

• Malignant meningiomas
• Prior cranial irradiation, except treatment of localized skin cancer of the face or scalp
• Patients having a concurrent primary cancer (except skin)
• Patients having another cancer controlled < 3 years
• Pregnant patients

90 Days, 15 years

Patients were assessed for adverse events with Radiation Therapy Oncology Group Common Toxicity Criteria. Patients were assessed weekly during the course of treatment. Post treatment, participants were evaluated for interval history and neurological function routinely at one month, every three months during the first year, four month intervals during the second year, twice yearly through year 5, and then yearly for the remainder of follow-up.