FET-PET-Guided Management of Pseudoprogression in Glioblastoma

Korábbi kezelés

• Previous treatment for recurrence of disease
• Any other concomitant disease that may influence PET imaging or clinical outcomes of this study, this includes but is not limited to: cerebral inflammatory diseases and other cancers with brain- or leptomeningeal metastases

Egyéb

• An enhanced lesion size of less than 1 cm on the index MRI. In the newest RANO PET criteria, it is advised to use FET-PET for increasing lesions only in cases with a minimum lesion size.
• Life expectancy of less than 6 months, determined by the treating physician
• Contra-indications for PET (claustrophobia, inability to lay still)
• Women of childbearing potential without adequate contraception

• Patients with a glioblastoma, IDH-wildtype, World Health Organization (WHO) grade 4, according to WHO 2021 criteria.
• Age ≥18 years
• New or increased enhancement within the high-dose radiation field (defined as within the 80% isodose line) on follow-up MRI
• Follow up MRI ≥3 months after the end of the standard-of-care temozolomide-based concomitant chemoradiation (60 Gy/30 fractions or 40 Gy/15 fractions). Of note, very early increase - within 3 months of last radiation - will not be grounds for inclusion because of the high rate of pseudoprogression and slightly lower diagnostic performance of FET-PET compared to the situation of increase beyond 3 months after last radiation. Patients with such very early increase may have subsequent further increase after 3 months post-radiation, causing (further) diagnostic doubt; these may be included at that later timepoint if they meet the other inclusion criteria.
• First moment of clinicoradiological uncertainty regarding the diagnosis (≥3 months after the end of chemoradiation): pseudoprogression or tumor recurrence. The determination of 'uncertainty' is made by the treating physician, preferably in the multidisciplinary tumor board, based on available clinical and standard-of-care MRI-data, which generally includes perfusion-MRI.
• Previous usage of bevacizumab as a symptom treatment is allowed. However, inclusion is only allowed at the first moment of clinical doubt between pseudoprogression and tumor recurrence, not at later timepoints.