Clinical and radiological data were retrospectively collected from magnetic resonance imaging (MRI) tests performed on 200 patients with recurrent GBM (confirmed histologically) at Gustave Roussy Cancer Campus (Villejuif, France) between 2006 and 2016 (based on the World Health Organization (WHO) classification of central nervous system tumours, Grade IV [26]). All enrolled patients must have received bevacizumab for the treatment of recurrent GBM after a first-line treatment failure, which consisted most often in surgery (72% patients) followed by post-operative chemoradiotherapy or chemoradiotherapy alone. Patients under 18 years or above 80 years of age were excluded from the analysis. Further cohort characteristics are detailed in Table 1.

Patient characteristic.

1 Patient data retrieved from clinical examination at the start of the bevacizumab treatment. 2 Delay between GBM diagnosis and start of bevacizumab treatment.

The study was approved by the institutional review board per RGPD provisions. The study was declared on the Health Data Hub site and the CNIL per RGPD recommendations. Additionally, all patients were informed of their enrolment in the study.