Pattern of F-18 FDG Uptake in Colon Cancer after Bacterial Cancer Therapy Using Engineered Salmonella Typhimurium: A Preliminary In Vivo Study

Figure 2

Three representative FDG PET/CT images after bacterial cancer therapy (BCT) using engineered Salmonella typhimurium. A tumor was generated in the right thigh of each mouse (BALB/c female mice, 6-weeks-old) using murine CT26 colon adenocarcinoma cells. After the tumor volume reached at least 180 mm³, BCT was performed by the intravenous injection of bacterial cells via the tail vein ( CFU/mouse in 100 μL PBS). FDG PET/CT images were acquired before and after BCT. Coronal PET/CT fusion images are shown. FDG uptake was measured as SUVmax. White arrows indicate FDG uptake in tumors before BCT (a–c). Yellow arrows (a & b) indicate decreased FDG uptake 1 day after BCT. The red arrow (c) indicates a tumor showing no decrease in FDG uptake after BCT. Abbreviations: FDG, 2-deoxy-2[¹⁸F]fluoro-D-glucose; dpi, days post-injection; SUVmax, maximum standardized uptake value; SUVmean, mean standardized uptake value; PBS, phosphate-buffered saline. CFU, colony-forming units.

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