Behandlungsunterschiede bei Glioblastom-Rezidiven: Eine Umfrage unter deutschen neuroonkologischen Spezialisten

The treatment of newly diagnosed glioblastomas follows standardized recommendations based on guidelines. Despite close interdisciplinary collaboration within the neuro-oncological tumor boards, there is uncertainty regarding the optimal treatment modality in patients with a recurrent glioblastoma due to limited evidence. This study aimed to investigate practice variation between neuro-oncology specialists and to identify patient characteristics that determine specific therapies.

We conducted an online survey using a structured questionnaire via the e-mail distribution lists of the German Society for Neurosurgery (DGNC), the Neurooncological Working Group (NOA) and the German Society for Radiooncology (DEGRO). Six recurrent glioblastoma cases with different patient characteristics were presented to neurosurgeons, neuro-oncologists, medical oncologists and radiation oncologists. In addition, we asked for practice characteristics of the participants.

The survey was filled in by 180 respondents of which 74 (41%) were neurosurgeons, 15 (8%) neuro-oncologists, 3 (2%) medical oncologists and 88 (49%) radiation oncologists. 49% of the participants were from university centres. 78% of the hospitals had participated in clinical oncology studies in the last 2 years. In the case of recurrence in young and clinical intact patients, most respondents were in favour of another tumour resection (88%) and of further adjuvant therapy (89%). There was no difference between the underlying specialties (89% of neurosurgeons, 88% of radiation oncologists, 93% of neurologists opted for another resection). However, there was substantial practice variation regarding the choice of adjuvant therapy (radiation vs. type of chemotherapy vs. experimental treatment options) between cases and specialties, but even within specialties. The clinical condition of the patient had the strongest influence on the decision to have another resection (only 53% were in favour of another resection in patients with low Karnofsky Performance Index), followed by age (only 70% were in favour with another resection in patients with higher age).

Our data show that the majority of specialists opts for re-resection and adjuvant therapy in recurrent glioblastoma in young patients without neurologic deficits. However, with regard to adjuvant therapy there was a high degree of treatment heterogeneity. This underlines the need for new evidence-based treatment standards.