Background: Re-irradiation (Re-RT) is offered widely in clinical routine, and has been established as a key element in the treatment of recurrent gliomas. At our center, generally re-resection is performed widely by an experienced neurosurgical team. Thus, Re-RT mostly offered to patients with macroscopic residuals or irresectable lesions, is applied later compared to other centers. Therefore, we sought to validate the Combs Prognostic Score developed in 2012 using our independent patient cohort. Patients and methods: We included 199 patients treated from 2002 until April 2016 for recurrent glioma at the Department of Radiation Oncology at the Klinikum Rechts der Isar, Munich. Different concepts of Re-RT were applied. Results: Median follow-up after Re-RT was 2.5 months. Median overall survival (OS) after Re-RT was 7.9 months for WHO IV gliomas, 11.3 months for WHO III gliomas, and 13.6 months for low-grade gliomas (WHO I/II). Univariate analyses confirmed the prognostic factors primary histology (p = 0.001), age (p = 0.002), and time between primary radiotherapy and Re-RT (p