Gastropet: Phase Ii Academic Clinical Trial Evaluating Sequential Fdgpet Driven Preoperative Treatment Strategy In Locally Advanced Oesophago-Gastric Cancer In The Context Of Mirna- And Immune-Based Biomarkers.

TPS202Background: The standard treatment approach in locally advanced oesophago-gastric cancer (OGC) contains surgery with perioperative chemotherapy (CXT). Nonetheless according to sequential 18FDG-PET-CT only 40–50% of the patients respond to CTX and non-responding patients would perhaps profit from concurrent radiotherapy (CRT). This phase II trial evaluates the sequential FDG-PET driven preoperative treatment strategy of early histopathological response and improved survival. Methods: Approximately 70 pts with resectable locally advanced OGC will be enrolled in this interventional, prospective, non-randomized multicenter trial. Pts will undergo baseline FDG-PET scan and will be given 1 cycle of CXT (FLOT or FOLFOX). FDG-PET scan will be repeated after 14 days and FDG-PET responders with ≥ 35% reduction in SUVmax from baseline to initial treatment will continue with CXT prior to surgery. FDG-PET non-responders will switch to the CRT (weekly carboplatin and paclitaxel with concurrent radiotherapy (45 Gy...