Progression of Focal to Diffuse Thyroid Uptake Detected by 18F-FDG PET/CT: Malignant Metastatic Disease or Benign Thyroiditis?. (September 2018)

• Record Type: Journal Article
• Authors: Thuillier, Philippe; Crouzeix, Geneviève; Descourt, Renaud; Salaun, Pierre-Yves; Abgral, Ronan
• Is Part Of: Clinical nuclear medicine. Volume 43:Number 9(2018)
• Publication Date: 2018-09
• Subjects: 18F-FDG PET/CT -- diffuse thyroid uptake -- metastasis -- lung cancer; Nuclear medicine -- Periodicals; Radioisotope scanning -- Periodicals; Nuclear Medicine -- Periodicals; 616.07575
• DOI: 10.1097/RLU.0000000000002168
• Languages: English
• ISSNs: 0363-9762

Abstract

Abstract : Abstract: A 49-year-old man was referred to our department for an assessment of a cerebral metastasis of unknown primary with 18 F-FDG PET/CT. This imaging led to detection of a suspected pulmonary primary carcinoma, as well as an incidental left focal thyroid uptake. An ultrasonography, performed a month later, revealed a thyroiditis aspect. An anti-PD1 immunotherapy was also proposed 2 months later after confirmation of a lung adenocarcinoma. A second baseline FDG PET/CT surprisingly showed a diffuse thyroid uptake. A fine-needle aspiration biopsy of thyroid parenchyma finally revealed a diffuse involvement from lung adenocarcinoma (ie, primary lung metastasis to the thyroid gland).