In a study activated in 1983 and closed in 1987, the Brain Tumor Research Center of the University of California and the Northern California Cancer Center evaluated the effect of bromodeoxyuridine in the treatment of glioblastoma multiforme. A total of 160 patients were evaluable of 173 entered. Patients were to receive a bromodeoxyuridine infusion of 0.8 g/m2 daily over 24 hours for 4 days of each of 6 weeks of radiotherapy directed to the tumor plus a margin delivering a total of 60 Gy. Eligibility requirements included Karnofsky performance status greater than or equal to 70, biopsy or resection and central pathology review by one of the authors. Following radiotherapy patients were to receive chemotherapy with procarbazine, CCNU, and vincristine for 1 year. Median survival was 55.7 weeks and time to failure, 34.5 weeks for the evaluable group of 160 patients. In a univariate analysis the variables that influence survival and time to failure were: age, Karnofsky performance status, bromodeoxyuridine dose and the delivery of at least one procarbazine, CCNU, and vincristine cycle following radiotherapy. In multivariate analysis, age, Karnofsky performance status, and bromodeoxyuridine dose remain significant for time to failure; age and Karnofsky performance status remain significant for survival.