Objective: 18 F-fluorodeoxyglucose positron emission tomography/computed tomography (18 F-FDG PET/CT) not only gives information about anatomical features of lung lesions but also about their metabolic activity. This study aimed to... more
Objective: 18 F-fluorodeoxyglucose positron emission tomography/computed tomography (18 F-FDG PET/CT) not only gives information about anatomical features of lung lesions but also about their metabolic activity. This study aimed to determine the mediastinal and parenchymal pathologies of the lung with false-positive FDG involvement and characteristics that could benefit differential diagnosis. Materials and Methods: This study retrospectively analyzed 1,924 subjects that underwent 18 F-FDG PET/CT from December 2010 to January 2015. Subjects with a maximum standardized uptake value (SUV max) value of ≥2.5 in the lung tissue, mediastinal lymph nodes with no primary lung malignancy, and a benign pathology result were included. Results: The mean age of the 143 subjects was 61.7±11.0 years. The pathologies anthracosis, granulomatous inflammatory events, and organized pneumonia (OP) were 64 (45%), 36 (25%), and 18 (13%) cases, respectively, in order of frequency. The median SUV max value of all lesions was 5.2 (min-max, 2.5-37.6). Moreover, mediastinal lymph node involvement was frequent (59%). The median SUV max value of anthracotic lesions was significantly lower than the median SUV max value of granulomatous and OP lesions (p<0.001 and p=0.007, respectively). No significant difference in the median SUV max value was noted between granulomatous and OP lesions. Conclusion: Anthracosis and tuberculosis should be considered as benign causes of mediastinal lymph node positivity in developing countries. 18 F-FDG PET/BT is an unreliable method for the differential diagnosis of benign diseases characterized by inflammation. Thus, metabolic activity evaluation is more suitable.
The combined use of PET scan with CT and fluorodeoxyglucose ([18F]FDG) can modify, in selected oncologic patients, the clinical management and care. We report here the case of a 63-year old female who showed increase serum level of CEA 3... more
The combined use of PET scan with CT and fluorodeoxyglucose ([18F]FDG) can modify, in selected oncologic patients, the clinical management and care. We report here the case of a 63-year old female who showed increase serum level of CEA 3 years following left colectomy for cancer. Ultrasound and CT (computed tomography) of the abdomen showed a single lesion in the segment II of the liver with portal thrombosis. [18F] FDG PET/CT revealed two lesions (the first area was histologically proven to be a colorectal carcinoma metastasis, the second one corresponded to the portal thrombosis). No antithrombotic drugs were administered and patient underwent chemotherapy for 4 courses (eloxatin plus 5-fluorouracil anf leucovorin). Liver resection was performed 2 weeks after the end of chemotherapy, and intraoperative ultrasound revealed a normal portal flow
