Annals of Nuclear Medicine and Sciences

False positive 18F-FDG utake in mediastinal lymph nodes for a patient with pulmonary adenocarcinoma: a case report


Yai-Chin Tsai1, Yung-Chie Lee2, Yih-Leong Chang3, Mei-Hsiu Pan1, Kai-Yuan Tzen1, Ruoh-Fang Yen1


1Department of Nuclear Medicine; 2Department of Surgery; 3Department of Pathology, National Taiwan University Hospital and National Taiwan University College of Medicine, Taipei, Taiwan



With 18F-FDG PET has been widely used for staging non-small cell lung cancer. We report herein a case of right-middle-lobe adenocarcinoma with multiple 18F-FDG-avid lymph nodes in mediastinum. The patient is a 73-year-old housewife who has received right middle lobe lobectomy and extensive dissection of mediastinal lymph nodes. Pathologic examination of all the forty-two lymph nodes dissected reveals anthracosis with reactive lymphoid hyperplasia. This example illustrates that 18F-FDG uptake of mediastinal lymph nodes in patients with non-small cell lung cancer may not be caused by malignancy.