Application of Dynamic [18F]-FDG PET/CT Multiparametric Imaging Leads to an Improved Differentiation of Benign and Malignant Lung Lesions

Purpose To evaluate the potential of whole-body dynamic (WBD) 2-deoxy-2-[¹⁸F]fluoro-D-glucose positron emission tomography/computed tomography ([¹⁸F]-FDG PET/CT) multiparametric imaging in the differential diagnosis between benign and malignant lung lesions. Procedures We retrospectively analyzed WBD PET/CT scans from patients with lung lesions performed between April 2020 and March 2023. Multiparametric images including standardized uptake value (SUV), metabolic rate (MR_FDG) and distribution volume (DV_FDG) were visually interpreted and compared. We adopted SUV_max, metabolic tumor volume (MTV) and total lesion glycolysis (TLG) for semi-quantitative analysis, MR_max and DV_max values for quantitative analysis. We also collected the patients’ clinical characteristics. The variables above with P-value < 0.05 in the univariate analysis were entered into a multivariate logistic regression. The statistically significant metrics were plotted on receiver-operating characteristic (ROC) curves. Results A total of 60 patients were included for data evaluation. We found that most malignant lesions showed high uptake on MR_FDG and SUV images, and low or absent uptake on DV_FDG images, while benign lesions showed low uptake on MR_FDG images and high uptake on DV_FDG images. Most malignant lesions showed a characteristic pattern of gradually increasing FDG uptake, whereas benign lesions presented an initial rise with rapid fall, then kept stable at a low level. The AUC values of MR_max and SUV_max are 0.874 (95% CI: 0.763–0.946) and 0.792 (95% CI: 0.667–0.886), respectively. DeLong’s test showed the difference between the areas is statistically significant (P < 0.001). Conclusions Our study demonstrated that dynamic [¹⁸F]-FDG PET/CT imaging based on the Patlak analysis was a more accurate method of distinguishing malignancies from benign lesions than conventional static PET/CT scans.