FMISO-PET in Brain Tumors and SCS Effect

Tumour ischaemia-hypoxia decreases the efficacy of radio-chemotherapy. Polarographic probe (and some 18F-FMISO-PET) studies have demonstrated prognostic value. Additionally hypoxia modification may increase survival. However, in high grade gliomas (HGG) there are not well established methods to evaluate and modify tumor hypoxia. We have previously described how spinal cord stimulation (SCS) can modify oxygenation, blood flow and metabolism in malignant gliomas. The aim of this study is to assess with 18F-FMISO PET: hypoxia in HGG and changes by spinal cord stimulation in a subset of patients. Additionally, the potential correlation with pathological, imaging and clinical parameters will be analyzed. 18F-FMISO PET will be performed in 20 patients with diagnosis of HGG: after surgery/biopsy and before radical treatment with 3D radiotherapy and temozolomide. A subset of 10 patients undergo two studies with 18F- FMISO-PET (one with SCS "off" and one with SCS "on"). In these patients, SCS will be connected from 1 hour before to 1 hour after each radiotherapy session, and in the day-time during the days of adjuvant temozolomide. 18F-FMISO PET results will not be taking into account for patient management. Patients will be followed at least until the end of adjuvant temozolomide (6 months after the end of concurrent radiochemotherapy).