Diagnostic value of 18F-FDG PET/CT for subsolid pulmonary nodules

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, SUVmax, 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 χ2 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) between 6 benign pGGN (0.78±0.25, range: 0.50-1.20) and 22 malignant pGGN (0.91±0.34, range: 0.40-1.70); SUVmax of 21 malignant PSN (2.10±1.16, range: 0.60-5.60) was higher than that of 22 malignant pGGN (t=-4.645, P 10%, the accuracy rates for PSN and pGGN were 65.0%(13/20) and 45.8%(11/24), respectively (χ2=1.616, P>0.05). Conclusion 18F-FDG PET/CT shows no clear advantage for diagnosis of pGGN, but is helpful for PSN. Key words: Lung neoplasms; Tomography, emission-computed; Tomography, X-ray computed; Deoxyglucose