Imaging Response in Malignant Glioma, RTOG 90-06:

Objective: The purpose of this study was to determine if radiographic response correlates with survival for patients treated patients with malignant gliomas treated on Radiation Therapy Oncology Group (RTOG) protocol 90-06. This study compared patients treated with hyperfractionated radiation and 1,3-bis(2-chloroethyl)1-nitrosourea (BCNU) to standard fractionation and BCNU. Methods: There were 453 patients evaluable. Histology included anaplastic astrocytoma (60) (AA), and glioblastoma multiforme (312) (GBM). All scans were forwarded to the RTOG central office and evaluated by a single reviewer without knowledge of outcome. Response at 4 months post initiation of therapy was evaluated by computed tomography or magnetic resonance image and compared with overall survival. Results: For patients with no tumor on the 4 month scan the median survival was 20.3 months and the 2 year survival 43%. Patients with partial or minor response had a median survival of 18.1 and 14.2 months and 2 year survival of 37% and 29%. Patients with progression had a median survival of 8.6 months and 2 year survival of 10%. Conclusions: Response rates were similar in both arms.