Assessment of indeterminate pulmonary nodules detected in lung cancer screening: Diagnostic accuracy of FDG PET/CT. (July 2016)

• Record Type: Journal Article
• Authors: Garcia-Velloso, Maria J.; Bastarrika, Gorka; de-Torres, Juan P.; Lozano, Maria D.; Sanchez-Salcedo, Pablo; Sancho, Lidia; Nuñez-Cordoba, Jorge M.; Campo, Arantza; Alcaide, Ana B.; Torre, Wenceslao; Richter, Jose A.; Zulueta, Javier J.
• Is Part Of: Lung cancer. Volume 97(2016)
• Page Start: 81
• Page End: 86
• Publication Date: 2016-07
• Subjects: AUC area under the curve -- I-ELCAP international early lung cancer action project -- FDG 2-[fluorine-18]-fluoro-2-deoxy-d-glucose -- FNA fine needle aspiration -- IQR interquartile range -- LDCT low dose computed tomography -- NLST national lung cancer screening trial -- PET positron emission tomography -- ROC receiver operating characteristic -- SUVmax maximum standardized uptake value; 18F-FDG -- PET/CT -- Lung nodule -- Lung cancer screening -- Diagnostic accuracy; Lungs -- Cancer -- Periodicals; Lung Neoplasms -- Abstracts; Lung Neoplasms -- Periodicals; Poumons -- Cancer -- Périodiques; Lungs -- Cancer; Periodicals; Electronic journals; Electronic journals; 616.99424
• DOI: 10.1016/j.lungcan.2016.04.025
• Languages: English
• ISSNs: 0169-5002

Abstract

Highlights: PET is accurate in characterizing indeterminate lung nodules detected in lung cancer screening. A nodule is likely to be benign or represent an indolent cancer if is PET negative. A lung cancer is highly suspected if the nodule is PET positive. Semi-quantitative analysis does not improve the accuracy of visual analysis for nodule assessment. Abstract: Background: A major drawback of lung cancer screening programs is the high frequency of false-positive findings on computed tomography (CT). We investigated the accuracy of selective 2-[fluorine-18]-fluoro-2-deoxy-d -glucose (FDG) Positron Emission Tomography/Computed Tomography (PET/CT) scan in assessing radiologically indeterminate lung nodules detected in lung cancer screening. Methods: FDG PET/CT was performed to characterize 64 baseline lung nodules >10 mm and 36 incidence nodules detected on low-dose CT screening in asymptomatic current or former smokers (83 men, age range 40–83 years) at high risk for lung cancer. CT images were acquired without intravenous contrast. Nodules were analyzed by size, density, and metabolic activity and visual scored on a 5-point scale for FDG uptake. Nodules were classified as negative for malignancy when no FDG uptake was observed, or positive when focal uptake was observed in the visual analysis, and the maximum standardized uptake value (SUVmax) was measured. Final diagnosis was based on histopathological evaluation or at least 24 months of follow-up. Results: A total of 100 nodules were included. The prevalence of lung cancer was 1%. The sensitivity, specificity, NPV and PPV of visual analysis to detect malignancy were 84%, 95%, 91%, and 91%, respectively, with an accuracy of 91% (AUC 0.893). FDG PET/CT accurately detected 31 malignant tumors (diameters 9–42 mm, SUVmax range 0.6–14.2) and was falsely negative in 6 patients. With SUVmax thresholds for malignancy of 1.5, 2, and 2.5, specificity was 97% but sensitivity decreased to 65%, 49%, and 46% respectively, and accuracy decreased to 85%, 79%, and 78% respectively (AUC 0.872). Conclusions: The visual analysis of FDG PET/CT scan is highly accurate in characterizing indeterminate pulmonary nodules detected in lung cancer screening with low-dose CT. Semi-quantitative analysis does not improve the accuracy of FDG PET/CT over that obtained with a qualitative method for lung nodule characterization.