Combined modality approach to treatment of malignant gliomas--re-evaluation of RTOG 7401/ECOG 1374 with long-term follow-up: a joint study of the Radiation Therapy Oncology Group and the Eastern Cooperative Oncology Group

Abstract

The Radiation Therapy Oncology Group (RTOG) and the Eastern Cooperative Oncology Group (ECOG) conducted a phase III trial in patients with malignant gliomas to evaluate 4 treatment arms: 1) 60 Gy to the whole brain; 2) 60 Gy plus 10-Gy boost; 3) 60 Gy plus carmustine (BCNU); and 4) 60 Gy plus semustine plus dacarbazine. Between September 1974 and March 1979, 626 patients with malignant gliomas were treated on protocol RTOG 7401/ECOG 1374. Each institution chose a subset of the treatments to which the patients would be randomized. Patients were stratified according to subset and randomized to the 4 treatment arms. There were no differences in survival among treatment arms. For patients greater than 60 years of age, the addition of chemotherapy to radiation therapy did not improve survival. For patients aged 40-60 years, there was a statistically significant increase in overall survival when BCNU was added to 60 Gy (P less than .01), with an increase in 2-year survival from 8% to 23%. This beneficial effect of BCNU is apparent in both histological groups (astrocytoma with atypical or anaplastic foci and glioblastoma multiforme). Although few confirmatory autopsies are available, long-term survival in patients with astrocytomas with atypical and anaplastic foci who were treated with 60 Gy plus BCNU (5-yr survival, 22%) suggests no significant late CNS toxicity, compared to 60 Gy alone (5-yr survival, 15%). This is confirmed by comparable neurological function in long-term survivors.