An extent of resection threshold for newly diagnosed glioblastomas

The authors identified 500 consecutive newly diagnosed patients with supratentorial GBM treated at the University of California, San Francisco between 1997 and 2009. Clinical, radiographic, and outcome parameters were measured for each case, including MR imaging-based volumetric tumor analysis.

The patients had a median age of 60 years and presented with a median Karnofsky Performance Scale (KPS) score of 80. The mean clinical follow-up period was 15.3 months, and no patient was unaccounted for. All patients underwent resection followed by chemotherapy and radiation therapy. The median postoperative tumor volume was 2.3 cm(3), equating to a 96% EOR. The median overall survival was 12.2 months. Using Cox proportional hazards analysis, age, KPS score, and EOR were predictive of survival (p