case_images: PMC8130706_01
case_images: (a) Maximum intensity projection image - increased fluorodeoxyglucose avidity in the midline of the neck. (b) Fused axial image - markedly increased metabolic activity in left-sided mass lesion (large single arrow). Another large solid-cystic mass lesion arising from the right lobe of the thyroid gland with mildly increased fluorodeoxyglucose uptake (small double arrow). (c) Axial computed tomography scan of the neck - left-sided mass lesion is not separable from the isthmus of the thyroid, thyroid cartilage, and obstructing the supraglottic larynx. (d) Small soft-tissue parenchymal nodules in the lingular segment of the left lung with minimally increased metabolic activity
case_images: IJNM-36-56-g001.jpg
case_images: PMC8130706_01_IJNM-36-56-g001.jpg
case_images: F1
case_images: The scan also showed small soft-tissue parenchymal nodules in the middle lobe of the right lung and lingular segment of the left lung with minimally increased FDG avidity [Figure 1].
case_images: (a) Neck mass biopsy - H and E x 40 - Poorly differentiated carcinoma with rhabdoid cells. (b) Lung biopsy - H and E x 20 Metastatic follicular carcinoma of thyroid
case_images: IJNM-36-56-g002.jpg
case_images: PMC8130706_01_IJNM-36-56-g002.jpg
case_images: F2
case_images: PAX8 was equivocal [Figure 2].
case_images: Axial section of follow-up positron emission tomography/computed tomography scan shows the partial regression of the metabolically active thyroid mass. The benign lesion in the right lobe of thyroid remains unchanged
case_images: IJNM-36-56-g003.jpg
case_images: PMC8130706_01_IJNM-36-56-g003.jpg
case_images: F3
case_images: The benign adenomatous right thyroid nodule showed no significant change in the appearance [Figure 3].