Diagnostic value of 18F-FDG PET/CT for subsolid pulmonary nodules / 中华核医学与分子影像杂志

ABSTRACT

Objective To determine the value of 18F-FDG PET/CT in the detection of subsolid pulmonary nodules.Methods The 18F-FDG PET/CT imaging data of 44 patients (35 males,9 females,mean age (68.05±9.89) years) with 49 subsolid pulmonary nodules were retrospectively analyzed.There were 28 pure ground-glass nodules (pGGN) and 21 part-solid nodules (PSN),which were all confirmed by postsurgical pathology or imaging results during follow-up.The lesion size (dmax),ground-glass opacity (GGO) percentage,SUV retention index (RI),and the positive rates on PET images were accessed.The correlation between SUVmax and lesion size and GGO percentage was analyzed by Pearson correlation analysis.The SUVmax between benign and malignant pGGN,and that between malignant pGGN and PSN,were compared using two-sample t test.The diagnostic accuracy was compared using x2 test.Results (1) Six pGGN were benign while 43 nodules (including 22 pGGN and 21 PSN) were malignant among the 49 nodules.(2) SUVmax was positively correlated with lesion size (r=0.500,P＜0.05) and was negatively correlated with GGO percentage (r=-0.605,P＜0.05) for PSN,while SUVmax was positively correlated with lesion size (r=0.375,P＜0.05) for pGGN.(3) SUVmax was not significantly different (t =-0.813,P＞0.05) between 6 benign pGGN (0.78±0.25,range0.50-1.20) and 22 malignant pGGN (0.91±0.34,range0.40-1.70);SUVmax of 21 malignant PSN (2.10±1.16,range0.60-5.60) was higher than that of 22 malignant pGGN (t=-4.645,P＜0.05).(4) When a nodule's activity being equal to or greater than that of mediastinal blood-pool was defined as malignancy,the accuracy rate of PSN (66.7％,14/21) was significantly higher than that of pGGN (9.1％,2/22; x2 =15.244,P ＜0.05).Based on the criteria for malignancy of RI＞10％,the accuracy rates for PSN and pGGN were 65.0％ (13/20) and 45.8％ (11/24),respectively (x2 =1.616,P＞0.05).Conclusion 18F-FDG PET/CT shows no clear advantage for diagnosis of pGGN,but is helpful for PSN.