{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T00:57:02Z","timestamp":1760144222146,"version":"build-2065373602"},"reference-count":23,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2024,3,31]],"date-time":"2024-03-31T00:00:00Z","timestamp":1711843200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Cancers"],"abstract":"<jats:p>Background: 18F-FDG PET\/CT is performed for the assessment of radioactive iodine non-avid disease in patients with DTC. In patients prepared by THW, increased pituitary uptake of 18F-FDG in the absence of pituitary disease may reflect the physiological activation of pituitary thyrotroph cells by hypothyroidism. This study aimed to compare pituitary 18F-FDG uptake in patients with DTC under THW vs. rhTSH stimulation. Methods: A total of 57 patients with DTC undergoing 18F-FDG PET\/CT (40 under THW and 17 under rhTSH stimulation) were retrospectively analyzed. Pituitary metabolism was expressed as maximum standardized uptake value (SUVmax) and as SUVratio using the right cerebellum as reference. Results: Pituitary hypermetabolism (SUVmax \u2265 4.1) was present in more patients in the THW group compared to the rhTSH group (62.5% vs. 23.5%; p = 0.01). Pituitary metabolism was significantly higher in the THW group compared to the rhTSH group, as assessed by either SUVmax (mean \u00b1 SD: 4.61 \u00b1 1.22, 95%CI: 4.22\u20135.00 vs. 3.34 \u00b1 0.86, 95%CI: 2.9\u20133.8; p &lt; 0.001) or SUVratio (0.52 \u00b1 0.11, 95%CI: 0.49\u20130.56 vs. 0.42 \u00b1 0.07, 95%CI: 0.38\u20130.46; p &lt; 0.001). Serum TSH levels correlated positively with SUVmax (r = 0.41, p &lt; 0.01) and SUVratio (r = 0.44, p &lt; 0.01) in the THW group only. Conclusions: The present findings support the hypothesis that pituitary hypermetabolism on 18F-FDG PET\/CT in patients with DTC undergoing THW is a common physiological response to hypothyroidism. Awareness of this physiological hypermetabolism is important to avoid potential pitfalls in image interpretation.<\/jats:p>","DOI":"10.3390\/cancers16071382","type":"journal-article","created":{"date-parts":[[2024,3,31]],"date-time":"2024-03-31T13:28:00Z","timestamp":1711891680000},"page":"1382","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Increased Pituitary Fluorine-18-Fluorodeoxyglucose Uptake in Patients with Differentiated Thyroid Cancer in Hypothyroidism versus under Recombinant Human Thyroid-Stimulating Hormone Stimulation"],"prefix":"10.3390","volume":"16","author":[{"given":"Xinyi","family":"Shi","sequence":"first","affiliation":[{"name":"Service of Endocrinology, Diabetology and Metabolism, Lausanne University Hospital, University of Lausanne, 1011 Lausanne, Switzerland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ilaria","family":"Giordani","sequence":"additional","affiliation":[{"name":"Service of Endocrinology, Diabetology and Metabolism, Lausanne University Hospital, University of Lausanne, 1011 Lausanne, Switzerland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4886-0611","authenticated-orcid":false,"given":"Marie","family":"Nicod Lalonde","sequence":"additional","affiliation":[{"name":"Service of Nuclear Medicine and Molecular Imaging, Lausanne University Hospital, University of Lausanne, 1011 Lausanne, Switzerland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9565-4941","authenticated-orcid":false,"given":"Gerasimos P.","family":"Sykiotis","sequence":"additional","affiliation":[{"name":"Service of Endocrinology, Diabetology and Metabolism, Lausanne University Hospital, University of Lausanne, 1011 Lausanne, Switzerland"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2024,3,31]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Klain, M., Zampella, E., Nappi, C., Nicolai, E., Ambrosio, R., Califaretti, E., Lamartina, L., Schlumberger, M., Deandreis, D., and Salvatore, D. 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