Survival after Stereotactic Radiosurgery for Recurrent Glioblastoma Multiforme

This retrospective analysis details the experience of a tertiary care center with survival and results for patients with recurrent glioblastoma multiforme (GBM) treated with stereotactic radiosurgery (SRS). Between August 1990 and June 1999, 23 patients were treated for recurrent GBM with SRS using either modified 6-MV linear accelerator (linac) or -knife. Twenty-two patients (96%) had an initial histological diagnosis of GBM, while 1 patient had an initial diagnosis of anaplastic astrocytoma that was biopsied at recurrence and found to have upgraded to GBM. The median Karnofsky performance score at the time of SRS was 80; the median age was 53. The median-treated tumor volume was 9.9 cm³, with a dose of 15 Gy delivered to the 60% isodose line. Median progression-free survival was 4.7 months. Median survival time after SRS was 10.3 months. No prognostic factors were found to be significant. Patients with a KPS of 80 or higher had longer median survival times than those with lower KPS scores, but this was not found to be statistically significant. Our results suggest that for selected patients with recurrent GBM, SRS appears to be an appropriate salvage therapy.