Imaging biological activity of a glioblastoma treated with an individual patient-tailored, experimental therapy regimen

Purpose To monitor the metabolic effects of an individual patient-tailored, experimental glioma therapy regimen that included repetitive multiple neurosurgical resections, radiosurgical interventions, and an adjuvant maintenance therapy based on the tyrosine kinase inhibitor imatinib in combination with the chemotherapeutic agent hydroxyurea (HU). Procedures Therapeutic effects were monitored in a 26-year-old male patient with a glioblastoma multiforme by multimodal imaging using sequential l-[methyl-(11)C]-methionine positron emission tomography (MET-PET) and MRI. The normalized MET uptake and volume of the metabolically active tumor were assessed sequentially. Results The individual patient-tailored, experimental glioma therapy caused a continuous decline of metabolically active tumor volume, associated with clinical remission over a period of more than two years. Conclusions MET-PET seems to be useful for monitoring patient-tailored, experimental glioma therapy regimens, especially when patients are treated with a multi-step therapeutic regimen. Monitoring and guidance of those experimental therapy regimens by MET-PET in a larger patient group are needed to confirm its clinical value.