18F-fluorothymidine (FLT) PET-CT for early response assessment in advanced pancreatic cancer.

e21093 Background: Advanced pancreatic cancer has a poor prognosis with a median survival of 6-10 months. There is a need for early non-invasive assessment of treatment response. We evaluated FLT PET-CT combined with a kinetic spatial filtering method (FLT-PETKSF) for detecting response to gemcitabine-based chemotherapy in advanced pancreatic cancer. Methods: Dynamic FLT PET-CT data were collected from patients with confirmed locally advanced or metastatic pancreatic cancer before and 2 weeks after the first cycle of chemotherapy. Changes in tumor FLT-PET variables with treatment were determined. Standardized uptake value (SUV) reduction of 18% was taken as cut-off for response. Voxel quantification of each tumor volume was performed on the filtered data. Each voxel-intensity was normalised by injected dose, body weight and decay corrected to obtain the SUV for the voxel. Changes in high intensity voxels (HiVox: SUV ≥ 2) - were computed. Results: Results of the first 5 patients are discussed. There were 4...