Tumour hypoxia imaging with 18F-fluoroazomycinarabinofuranoside PET/CT in patients with locally advanced rectal cancer

Objective: The aim of this study was to investigate the feasibility of 18F-fluoroazomycinarabinofuranoside ( 18F-FAZA) positron emission tomography (PET)/computed tomography (CT) in patients with locally advanced rectal cancer. Materials and Methods: The study included 14 patients with locally advanced rectal cancer. Before chemoradiotherapy, PET/CT with F-FAZA was performed with static 15 min images 2 h after injection of 18F-FAZA. Attenuation correction was obtained with a low-dose CT, and a contrast-enhanced CT was performed immediately after the PET scan. Results: 18F-FAZA uptake [mean and maximum standardized uptake value (SUVmean) and (SUVmax)] was significantly higher in rectal tumours than in both muscles (Pmax, SUV mean, T/M and T/I values were significantly higher in the entire tumour volume compared with the tumour volume adjusted for scatter from the urinary bladder (P18F-FAZA PET/CT is feasible for visualization of hypoxia in patients with rectal cancer, but scattered activity from the urinary bladder should be taken into consideration.