Methods
133 and 72 consecutive patients aged 65 years and older who underwent surgery and needle biopsy for intracranial primary (de
novo) GBM between 1997 and 2007 were retrospectively reviewed. Among these patients, 40 who underwent surgical resection were
matched with 40 who underwent needle biopsy alone for factors consistently shown to be associated with survival [age, Karnofsky
Performance Scale (KPS) indexing, eloquent involvement, radiation, temozolomide]. Survival was expressed as estimated Kaplan–Meier
plots, and log-rank analysis was used to compare survival curves.