18F-FDG PET/CT-related metabolic parameters and their value in early prediction of chemotherapy response in a VX2 tumor model.

摘要

OBJECTIVE: This study acquired fluorine-18-deoxyglucose (FDG) kinetic parameters prior and subsequent to cisplatin chemotherapy so as to define the optimal parameters for early prediction of chemotherapy response. METHODS: A total of 12 non-tumor-bearing rabbits were used to obtain noninvasive input function, five VX2 tumor-bearing rabbits were used for validation and 32 tumor-bearing rabbits underwent 4 mg kg(-1) cisplatin chemotherapy. Dynamic FDG PET/CT was performed at pretherapy, Day 0, Day 1, Day 7 and Day 14 after cisplatin administration. With the application of a three-compartment model, influx index (Ki), k1, k2, k3 and k4 were noninvasively obtained. RESULTS: Sensitive (SG) and insensitive groups (ISG) were defined based on their volume on Day 7. k1, Ki, SUVmean, and SUVmax showed significant decreases in SG vs. ISG at Day 0 (P<.076-0.0001). k1 demonstrated sustained (up to Day 7) differences (P<.028-0.0072), and k2, k3 and k4 showed no significant differences at any time point (P>.05). Soon after cisplatin administration, GLUT-1 expression was greatly decreased in SG vs. ISG. CONCLUSIONS: The parameters of SUVmax, SUVmean, Ki and k1 were valuable for the early prediction of chemotherapy response. k1 had a wider observation window compared to SUVmean, SUVmax and Ki, and k1 also reflected the changes in GLUT-1 expression.