The treatment of recurrent glioblastoma is, beside of its abundance in clinical practice,
still under discussion. Patients presenting with recurrent disease are therefore treated
within individual concepts, largely based on small prospective trials, retrospective
evaluations or case reports. Therefore, the treatment ranges from best supportive care over
primary systemic treatments towards local therapies such as radiotherapy or surgical
resection. Even if there might be a large selection bias, local therapies with or without
concomitant or adjuvant chemotherapy seem to promise the largest prognostic benefit. Whether
the combination of surgical resection and adjuvant radiotherapy improves survival, as it does
within the primary situation, is unknown.
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).
Whether patients might benefit from a postoperative radiotherapy of the resection cavity
after complete extirpation of all macroscopic tumor is key question of this protocol.
To answer this question, the considered standard of care after complete resection, namely
observation with or without adjuvant systemic therapy, will be compared to a postoperative
normofractionated stereotactic radiotherapy towards the resection cavity within an open
label, randomized trial. The prescribed total dose will be 46 Gy in 2 Gy fractions of 36 Gy
in 3 Gy fractions depending on the treatment volume.
Concerning safety, side effects will be monitored prospectively. Safety parameters will be
compared between both arms of the study. Furthermore, measures for quality of life,
neurocognitive function as well as neuroimaging features will be evaluated prospectively.