Between 1985 and 1995, 46 patients underwent craniotomy for glioblastoma multiforme. The mean age was 47, varying from 9 to 71 years. The influence of such prognostic factors as age, preoperative Karnofsky score, extent of resection, tumour site, tumour size, radiotherapy, reoperation as well as initial symptoms upon survival were studied. Of these, gross complete removal, radiotherapy, preoperative Karnofsky score, and reoperation were shown to be statistically significant to the survival time according to logrank and univariate tests. However, age, preoperative Karnofsky score, tumour size and temporal localisation remained as significant factors in multivariate analysis. The overall median survival was 53 weeks, with no patients surviving more than 3 years. Of the patients, 41% survived over a year and 8.6% lived over two years. Twenty-six patients developed a recurrent mass after an interval of 32 weeks. The median interval time from operation to recurrence was longer in those patients who underwent gross removal than in those who had a subtotal resection, 28.2 against 20 weeks (P < 0.05). Of patients who had a recurrent mass, 16 were reoperated on, with a subsequent median survival time of 26.5 weeks. Our experience suggests that the survival of patients with glioblastoma depends on many factors, including radical surgery as an initial step. In addition, the gross total removal of the tumour also delays the development of recurrence. (C) 1997 Elsevier Science B.V.