The result of surgical resection might have an impact as well. Several case reports, retrospective evaluations and prospective studies have also included patients with remaining gross tumor after maximum save resection. In these trials, radiotherapy was associated with improvements in progression free as well as overall survival. Therefore, the influence of neuroimaging on prognosis is currently evaluated within the GLIA-A trial. Furthermore, stereotactic radiotherapy with or without an experimental systemic therapy is currently investigated within another multicenter randomized trial (NOA-12).