The object of this study is to evaluate the efficacy of a high dose of carboplatin in 20 patients operated on for high grade glioma (Group A) compared with a matched control (Group B) treated with BCNU administered after radiotherapy. The toxicity profile has been evaluated during the therapy. The survival of patients entering this study was measured in terms of months: the mean survival time was 10.45 months and the median 11.0 months in the group treated with carboplatin (8 patients are still alive); the 18-month survival rate was 10%. The mean survival time of the control group was 9.85 months and the median 10.5 months; no patients are still alive and the 18-month survival rate was 0%. On the basis of our phase II clinical study, we could conclude that i.v. administration of high-doses of carboplatin in high grade gliomas is generally well tolerated and the results are better than those of a matched control treated with 1-2 courses of BCNU (low-dose). The adjuvant treatment and the role of carboplatin in the therapy of high grade gliomas is discussed.