P09.45 Impact of extent of resection for long-term survival in patients with glioblastoma

Abstract

AbstractOBJECTIVES: Survivors who live more than three years after diagnosis of glioblastoma (GBM), are referred as long-term survivors. Only 3-5% of glioblastoma patients are reported to survive longer than three years. However, we are having an increasing number of long-term survivors owing to advances in treatment. Our study explored the efficiency of the currently identified prognostic factors on the long-term survival of GBM patients. The authors reviewed all patients with newly diagnosed brain GBM who underwent surgery followed by combined chemoradiotherapy between 2005 and 2013, with a minimum of 3 years of follow-up. Clinical information was compared between long-term and short-term survivors. Fifty-two (26.8%) patients survived more than three years. When gross total resection was achieved, 34.6% (44/127) of the patients survived more than three years, compared to 16.0% (20/125) patients survived more than three years when gross total resection was not achieved (p < 0.001). The median overall survival was 20.8 (95% confidence interval [CI] 17.7-23.9) months, and progression-free survival was 12.7 months. In univariate analysis, patients who are younger than 50 years, underwent gross total resection in initial surgery, with tumors smaller than 3.5cm, 1p/19q co-deleted, Isocitrate dehydrogenase (IDH) mutated, o6-DNA-methylguanine methyltransferase (MGMT) promoter methylated, Karnofsky performance scale more than 70, without cerebrospinal dissemination were significantly related to long-term survivors. In multivariate analysis, Age (<50), MGMT methylation, gross total resection were significant factors for long-term survival. In GBM patients who received current best treatment with temozolomide, more than one-fourth of patients survived more than three years. The extent of resection is a powerful predictor of long-term survival which can be controlled by the surgeon.