Abstract: Diffuse low grade gliomas (DLGG) are continuously progressive primary brain neoplasms that lead to neurological deficits and death. Treatment strategies are controversial. Randomized trials establishing the prognostic value of surgery do not exist. Here, we report the results of a nine-year near-randomized patient distribution between resection and biopsy. Until 2012, the Department of Neurosurgery and the Department of Stereotactic Neurosurgery at the University Medical Center Freiburg were organized as separate administrative units both coordinating DLGG patient treatment independently. All consecutive adult patients with a new diagnosis of DLGG by either stereotactic biopsy or resection were included. Pre- and post-operative tumor volumetry was performed. 126 patients, 87 men (69%), 39 women (31%), median age 41 years, were included. 77 (61%) were initially managed by biopsy, 49 (39%) by resection. A significant survival benefit was found for patients with an initial management by resection (5-year OS 82% vs. 54%). The survival benefit of patients with initial resection was reserved to patients with a residual tumor volume of less than 15 cm3. Maximum safe resection is the first therapy of choice in DLGG patients if a near-complete tumor removal can be achieved. Accurate prediction of the extent-of-resection is required for selection of surgical candidates

Abstract: Leptomeningeal metastasis (LM) of high grade gliomas (HGG) can lead to devastating diseasecourses. Understanding of risk factors for LM is important to identify patients at risk. We reviewedpatient records and magnetic resonance imaging (MRI) of all patients with a first diagnosis ofHGG who underwent surgery in our institution between 2008 and 2012. To assess the influence ofpotential risk factors for LM and the impact of LM on survival multivariate statistics were performed.239 patients with a diagnosis of HGG and at least 6 months of MRI and clinical follow-up wereincluded. LM occurred in 27 (11%) patients and was symptomatic in 17 (65%). A strong correlationof surgical entry to the ventricle and LM was found (HR: 8.1). Ventricular entry was documentedin 137 patients (57%) and LM ensued in 25 (18%) of these. Only two (2%) of 102 patients withoutventricular entry developed LM. Median overall survival of patients after diagnosis of LM (239 days)was significantly shorter compared to patients without LM (626 days). LM is a frequent complicationin the course of disease of HGG and is associated with poor survival. Surgical entry to the ventricle isa key risk factor for LM