P11.42.a long- and shortime survivors with glioblastoma identified by flt pet/mr and metabolomics

Abstract BACKGROUND Patients with glioblastoma still have a dismal prognosis despite multimodal treatment with surgery and radiochemotherapy. Sometimes these patients also suffer from difficulties in the interpretation of outcome from treatment. Since most patients affected by glioblastoma have a short survival it is of outermost importance that ineffective treatment is discontinued in time to spare them from unwanted side effects. MATERIAL AND METHODS 48 patients with suspected glioblastoma were included in a clinical study at Umeå University Hospital between the years 2015-2019. Patients were treated according to clinical routines with surgery and radiochemotherapy and within the framework of the study they performed up to four 18F-flourothymidine (FLT) PET/MR and serial blood-tests for metabolomics. Blood samples were analyzed at Metabolon, USA and the metabolomic pattern were compared with clinical and radiomic data. RESULTS The measures of standardized uptake values (SUV) and tumor volumes show a higher SUV for short-time survivals compared to long-time survivors but only a significant difference for the MR-measures Vtumor, Vtotal after 6 weeks of treatment. Regarding blood samples the metabolite patterns could separate patients living long (>3 years) and patients living short (<500 days) in blood samples taken both preoperatively and after six weeks of radiochemotherapy. CONCLUSION New methods are needed to accurate assess prognosis and outcome of treatment for patients with glioblastoma. This clinical study gives new insights in foreseeing prognosis for patients with glioblastoma by using 18F-flourothymidine (FLT) PET/MR and also by serial blood sampling during treatment. Both results of FLT PET/MR and the impact of metabolomics will be presented and discussed at the conference.