11C-methionine

Glioblastoma multiforme (GBM) is the most common primary brain cancer. The treatment of GBM consists of a combination of surgery and subsequent oncological therapy, i.e. radiotherapy, chemotherapy, or combination of both at te same time. If post-operative oncological therapy involves irradiation, magnetic resonance imaging (MRI) is planned. Unfortunately, in some cases, a very early worsening (progression) or return (recurrence) of the disease is observed several weeks after the surgery, i.e. rapid early progression (REP). Radiotherapy planning is based on this MRI in all patients. However, a subset of patients with REP have a less favorable prognosis with this treatment management. The investigators therefore assume that these patients need a more thorough examination to form a precise radiotherapy plan. The project focuses on this group of patients with a less favorable prognosis (with a more aggressive disease). Patients who develop REP within approximately 6 weeks after surgery will have PET/CT (positron emission tomography in combination with computed tomography) examinations using the radiopharmaceutical 11C-methionine in addition to standard practice. PET is one of the most modern methods of molecular imaging, a non-invasive in vivo method that allows physicians to study processes in the human body using radiolabeled radiopharmaceuticals. 11C-methionine is an example of a radiolabeled (carbon 11) amino acid - a source of energy for tumor cells and a building material for new proteins. This radiopharmaceutical is commonly used in the diagnosis of brain tumors and in the evaluation of response to treatment. For patients who undergo this examination, the radiotherapy planning will be adjusted based on it. The purpose of clinical trial is to improve the prospects of patients with REP.