Eight of 57 patients (14%) with malignant astrocytomas lived at least 2 years. The mean survival time was 143 weeks (range, 104 to 250 weeks). All of the patients were treated with operation, radiation, and chemotherapy. Four of the 8 patients died because of tumor recurrence, 1 died from a second primary tumor, 2 died of causes unrelated to the tumor, and 1 is still alive. Diffuse cortical dysfunction associated with cortical atrophy that could not be related to tumor regrowth and was not explained by focal deficits, psychotic or depressive thought disorders, metabolic or endocrine abnormalities, or hydrocephalus developed in the 3 longest-surviving patients. The diffuse dysfunction was initially apparent only through psychometric testing, but eventually became so disabling as to result in 2 of the 3 patients retiring from work. Although small, but gratifying, gains have been made in the treatment of patients with malignant brain tumors, accompanying these gains have been problems of a magnitude that is only now beginning to be appreciated.