P03.12 Complete versus incomplete resection in newly diagnosed Glioblastoma: Impact on functional Outcome

Abstract

Abstract BACKGROUND Surgical resection of (GBM) has three goals: Tissue acquision to establish a histological and molecular diagnosis, prolongation of survival and improvement of neurological impairment. Regarding survival gain, complete resection is superior to incomplete resection. However, no data are available, whether complete resection also has a higher impact on neurological improvement rates compared to incomplete resection. The goal of our study was to compare the reduction of focal neurological deficits and improvement of functional independency in newly diagnosed GBM patients receiving a complete vs. incomplete resection. MATERIAL AND METHODS A cohort of 299 patients (mean age 60.6 year; female/male ratio 124/175) were included. Neurological and functional independence status was measured by the medical research neurological performance status (NPS), the Karnofsky performance score (KPS) and the presence of seizures. Focal neurological impairment regarding hemiparesis, aphasia visual field (VFD) and cranial nerve deficits (CND) was recorded and semi - quantitatively rated pre- and postoperatively as well as at follow up. The extent of resection (EOR) was analyzed using early postoperative MRI scanning and was classified in either complete (CR), incomplete (IR) resection. RESULTS The complete and incomplete resection groups were balanced regarding gender, age, preoperative KPS, MGMT and IDH1 status. Median overall survival (OS) was 14.5 months, showing a significant benefit of complete resection (17.9 vs. 11.5; p = 0.0001). Impaired KPS was detected in 87.9%, epileptic seizures were displayed by 31.4% of all patients, the most frequent focal deficit was aphasia with 25.1%, followed by CND (20.1%) and hemiparesis (17.1%). KPS was improved in 45.6%, seizures were reduced in 91.5%, the highest improvement of focal deficit was achieved in CND (71.7%) the lowest in VFD (44.8%). Complete resection did achieve a higher improvement rate in hemiparesis (79.1% vs. 49.8%; p = 0.03) and seizure activity (97.7% vs. 86.3%; p = 0.04). In all other domains the improvement rates after complete resection were not significantly different to incomplete resection. Finally, complete resection did not show a higher rate of postsurgical worsening rate in any of the domains. CONCLUSION Complete resection is safe and does convey superior improvement rates of epileptic seizures and hemiparesis.