Diagnosis of solitary pulmonary nodule with ¹⁸F-FDG and ¹⁸F-FLT PET/CT

Objective To study the diagnostic value of combined ¹⁸F-fluorothymidine（¹⁸F-FDG） and ¹⁸F-fluorodeoxiglucose（¹⁸FFLT） PET/CT imaging for solitary pulmonary nodule（SPN）. Methods ¹⁸F-FDG and ¹⁸F-FLT PET/CT imaging were performed for patients with SPN.Final diagnosis of SPN was made based on the findings of pathological examination and 6-month follow-up.The diagnostic value of ¹⁸F-FDG and ¹⁸F-FLT PET/CT for SPN was compared using semi-quantitative SUV_max and FLT/FDG ratio. Results Malignant and benign tumors were found in 6 and 9 of the 15 SPN patients,respectively.The SUV_max was significantly lower on ¹⁸F-FLT imaging than on ¹⁸F-FDG imaging.However,the SUV_max was greater for malignant tumor than for benign tumor on either ¹⁸F-FDG or on ¹⁸F-FLT image.The diagnostic accuracy,sensitivity and specificity of SUV_max were 66.7%,83.3%,55.6% on ¹⁸F-FDG PET/CT imaging and 80%,66.7%,88.9% on ¹⁸F-FLT imaging. Conclusion ¹⁸F-FLT,as a novel imaging tracer of PET/CT for the characteristics of cell proliferation is of certain diagnostic value for SPN.¹⁸F-FDG combined with ¹⁸F-FLT can increase the diagnostic value for SPN.