[Study on three patients with malignant glioma showing tumor reduction during maintenance therapy with MCNU].

Tumor regression occurred in three of 19 patients (15.8%) with malignant glioma during maintenance therapy using MCNU. In two patients, the tumor reduced 5 and 8 months after the initial treatment, respectively. In the remaining patient, though the maintenance therapy was interrupted for a while and consequently the tumor size increased, readministration of MCNU reduced the tumor size two months later. Therefore, since the antitumor activity of MCNU against malignant glioma seems to require a certain time depending on the case, it is recommended that MCNU be given as maintenance therapy for at least half a year.