Usefulness of fluorodeoxyglucose positron emission tomography in malignancy of pulmonary artery mimicking pulmonary embolism.

The role of (18) F-fluorodeoxyglucose positron emission tomography/computed tomography ((18) F-FDG PET/CT) in evaluating pulmonary artery lesions has not yet been established. The purpose of this study is to evaluate the usefulness of (18) F-FDG PET/CT imaging in differentiating malignant from benign pulmonary artery (PA) lesions. In this retrospective study, 18 subjects with 26 low-attenuated filling defects suspicious for PA malignancy on contrast-enhanced chest CT were enrolled; all of whom subsequently underwent (18) F-FDG PET/CT. The maximum standardized uptake value (SUVmax) for all PA lesions, defined as the (18) F-FDG uptake, was measured. The final diagnosis was then determined by pathological findings, follow-up chest CT or clinical follow-up, and compared with the PET imaging. In total, 6 PA sarcomas, 5 tumour embolism, and 15 pulmonary thromboembolism (PTE) occurred in this cohort. Not only was the SUVmax of the malignant PA lesions (10.2 ± 10.8) was significantly higher than that associated with PTE (1.7 ± 0.3; P < 0.001), no overlap occurred between groups. Conversely, no statistically significant difference in SUVmax occurred between PA sarcomas (12.8 ± 14.7) and tumour embolism (7.0 ± 1.32; P = 1.000).  (18) F-FDG PET/CT is a useful imaging modality for differentiating malignant from benign PA lesions in patients with inconclusive low-attenuation filling defects on contrast-enhanced chest CT. © 2012 The Authors. ANZ Journal of Surgery © 2012 Royal Australasian College of Surgeons.