{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,20]],"date-time":"2026-07-20T14:17:55Z","timestamp":1784557075719,"version":"3.55.0"},"reference-count":16,"publisher":"Bioscientifica","issue":"1","license":[{"start":{"date-parts":[[2024,1,1]],"date-time":"2024-01-01T00:00:00Z","timestamp":1704067200000},"content-version":"unspecified","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["edm.bioscientifica.com"],"crossmark-restriction":true},"short-container-title":[],"published-print":{"date-parts":[[2024,1,1]]},"abstract":"<jats:sec>\n                    <jats:title>Summary<\/jats:title>\n                    <jats:p>Unlike medullary thyroid carcinomas, follicular cell-derived thyroid malignancies have rarely been associated with paraneoplastic endocrine syndromes. An ultrarare case of a middle-aged man with heavily treated broadly metastatic radioactive iodine-refractory widely invasive H\u00fcrthle cell carcinoma (HCC) of the thyroid with two synchronous paraneoplastic endocrine syndromes, T3 thyrotoxicosis and hypercalcemia of malignancy, is discussed here. The levothyroxine-induced T3 thyrotoxicosis was a gradual process that became more noticeable as the tumor burden, refractory to different modalities of therapy, expanded. The 1,25-dihydroxyvitamin-D-mediated hypercalcemia, on the other hand, developed in a manner of weeks, as it usually happens. It is important to emphasize that in patients with metastatic H\u00fcrthle cell and follicular carcinomas of the thyroid, on TSH suppressive therapy, the unexplained and progressive decline in FT4 and rise in FT3 levels, resulting in an elevated FT4\/FT3 ratio, could be an indication of augmented type 1 (D1) and\/or type 2 (D2) deiodinase expression in tumoral tissue, causing an increased conversion from the prohormone T4 into the active metabolite T3 via outer ring deiodination.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Learning points<\/jats:title>\n                    <jats:list list-type=\"bullet\">\n                      <jats:list-item>\n                        <jats:p>Albeit extremely rare, some patients with thyroid cancer can present with more than one concomitant paraneoplastic syndrome.<\/jats:p>\n                      <\/jats:list-item>\n                      <jats:list-item>\n                        <jats:p>Although medullary thyroid carcinoma is the thyroid malignancy that is usually associated with paraneoplastic endocrine syndromes, follicular cell-derived thyroid cancers have been rarely described as being the culprit.<\/jats:p>\n                      <\/jats:list-item>\n                      <jats:list-item>\n                        <jats:p>In patients with metastatic H\u00fcrthle cell and follicular thyroid carcinomas, the unexplained and progressive decline in FT4 and rise in FT3 levels could be an indication of augmented type 1 (D1) and\/or type 2 (D2) deiodinase expression in tumoral tissue, causing an increased conversion from T4 into T3 leading to T3 thyrotoxicosis.<\/jats:p>\n                      <\/jats:list-item>\n                    <\/jats:list>\n                  <\/jats:sec>","DOI":"10.1530\/edm-23-0118","type":"journal-article","created":{"date-parts":[[2024,1,31]],"date-time":"2024-01-31T09:41:57Z","timestamp":1706694117000},"update-policy":"https:\/\/doi.org\/10.1530\/crossmarkpolicy-2","source":"Crossref","is-referenced-by-count":1,"title":["Two synchronous paraneoplastic endocrine syndromes in a 53-year-old male with broadly metastatic widely invasive H\u00fcrthle cell carcinoma"],"prefix":"10.1530","volume":"2024","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-0396-5946","authenticated-orcid":true,"given":"John J","family":"Orrego","sequence":"first","affiliation":[{"name":"Department of Endocrinology and Metabolism, Kaiser Foundation Health Plan of Colorado, Denver, Colorado, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Joseph A","family":"Chorny","sequence":"additional","affiliation":[{"name":"Department of Pathology, Kaiser Foundation Health Plan of Colorado, Denver, Colorado, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"416","reference":[{"key":"bib1","series-title":"European Archives of Oto-Rhino-Laryngology","first-page":"32","article-title":"Paraneoplastic syndromes in patients with primary malignancies of the head and neck: four cases and a review of the literature","volume":"263","author":"Baijens","year":"2006","unstructured":"Baijens LW & Manni JJ. Paraneoplastic syndromes in patients with primary malignancies of the head and neck: four cases and a review of the literature. European Archives of Oto-Rhino-Laryngology200626332\u201336. (https:\/\/doi.org\/10.1007\/s00405-005-0942-1)"},{"key":"bib2","series-title":"Endocrine Pathology","first-page":"303","article-title":"Paraneoplastic endocrine syndromes: a review","volume":"14","author":"DeLellis","year":"2003","unstructured":"DeLellis RA & Xia L. Paraneoplastic endocrine syndromes: a review. Endocrine Pathology200314303\u2013317. (https:\/\/doi.org\/10.1385\/ep:14:4:303)"},{"key":"bib3","series-title":"WHO Classification of Tumours of Endocrine Organs","first-page":"65","author":"Lloyd","year":"2017","unstructured":"Lloyd RVOsamura RYKloppel G & Rosai JWHO Classification of Tumours of Endocrine Organs, 4th ed., pp. 65\u2013143. Lyon: International Agency for Research on Cancer (International Arctic Research Center)2017."},{"key":"bib4","series-title":"Journal of Clinical Endocrinology and Metabolism","first-page":"55","article-title":"Clinical and molecular features of H\u00fcrthle cell carcinoma of the thyroid","volume":"100","author":"Chindris","year":"2015","unstructured":"Chindris AMCasler JDBernet VJRivera MThomas CKachergus JMNecela BMHay IDWestphal SAGrant CS, et al.Clinical and molecular features of H\u00fcrthle cell carcinoma of the thyroid. Journal of Clinical Endocrinology and Metabolism201510055\u201362. (https:\/\/doi.org\/10.1210\/jc.2014-1634)"},{"key":"bib5","series-title":"Endocrine-Related Cancer","first-page":"32","article-title":"Deiodinases in thyroid tumorigenesis","volume":"30","author":"Angela De Stefano","year":"2023","unstructured":"Angela De Stefano MPorcelli TSchlumberger M & Salvatore D. Deiodinases in thyroid tumorigenesis. Endocrine-Related Cancer20233032\u201336. (https:\/\/doi.org\/10.1530\/ERC-23-0015)"},{"key":"bib6","series-title":"Nuklearmedizin","first-page":"186","article-title":"T3-Hyperthyreose bei metastasierendem follikul\u00e4ren Schilddr\u00fcsenkarzinom unter Substitutionstherapie [T3 hyperthyroidism with metastatic follicular thyroid carcinoma in substitution therapy]","volume":"35","author":"Lang","year":"1996","unstructured":"Lang M & Flesch M. T3-Hyperthyreose bei metastasierendem follikul\u00e4ren Schilddr\u00fcsenkarzinom unter Substitutionstherapie [T3 hyperthyroidism with metastatic follicular thyroid carcinoma in substitution therapy]. Nuklearmedizin199635186\u2013189. (https:\/\/doi.org\/10.1055\/s-0038-1629806)"},{"key":"bib7","series-title":"Journal of Clinical Endocrinology and Metabolism","first-page":"594","article-title":"Overexpression of type 2 iodothyronine deiodinase in follicular carcinoma as a cause of low circulating free thyroxine levels","volume":"88","author":"Kim","year":"2003","unstructured":"Kim BWDaniels GHHarrison BJPrice AHarney JWLarsen PR & Weetman AP. Overexpression of type 2 iodothyronine deiodinase in follicular carcinoma as a cause of low circulating free thyroxine levels. Journal of Clinical Endocrinology and Metabolism200388594\u2013598. (https:\/\/doi.org\/10.1210\/jc.2002-020921)"},{"key":"bib8","series-title":"Thyroid","first-page":"615","article-title":"Thyroxine to triiodothyronine hyperconversion thyrotoxicosis in patients with large metastases of follicular thyroid carcinoma","volume":"16","author":"Takano","year":"2006","unstructured":"Takano TMiyauchi AIto Y & Amino N. Thyroxine to triiodothyronine hyperconversion thyrotoxicosis in patients with large metastases of follicular thyroid carcinoma. Thyroid200616615\u2013618. (https:\/\/doi.org\/10.1089\/thy.2006.16.615)"},{"key":"bib9","series-title":"Journal of Clinical Endocrinology and Metabolism","first-page":"2239","article-title":"3,5,3\u2032-triiodothyronine thyrotoxicosis due to increased conversion of administered levothyroxine in patients with massive metastatic follicular thyroid carcinoma","volume":"93","author":"Miyauchi","year":"2008","unstructured":"Miyauchi ATakamura YIto YMiya AKobayashi KMatsuzuka FAmino NToyoda NNomura E & Nishikawa M. 3,5,3\u2032-triiodothyronine thyrotoxicosis due to increased conversion of administered levothyroxine in patients with massive metastatic follicular thyroid carcinoma. Journal of Clinical Endocrinology and Metabolism2008932239\u20132242. (https:\/\/doi.org\/10.1210\/jc.2007-2282)"},{"key":"bib10","series-title":"Endocrine Journal","first-page":"303","article-title":"Anaplastic thyroid carcinoma with humoral hypercalcemia of malignancy (HHM): an autopsy case report","volume":"51","author":"Iwai","year":"2004","unstructured":"Iwai HOhno Y & Aoki N. Anaplastic thyroid carcinoma with humoral hypercalcemia of malignancy (HHM): an autopsy case report. Endocrine Journal200451303\u2013310. (https:\/\/doi.org\/10.1507\/endocrj.51.303)"},{"key":"bib11","series-title":"Journal of Clinical Ultrasound","first-page":"438","article-title":"Occult anaplastic thyroid carcinoma associated with marked hypercalcemia","volume":"18","author":"Takashima","year":"1990","unstructured":"Takashima SMorimoto SIkezoe JKokado Y & Kozuka T. Occult anaplastic thyroid carcinoma associated with marked hypercalcemia. Journal of Clinical Ultrasound199018438\u2013441. (https:\/\/doi.org\/10.1002\/jcu.1870180513)"},{"key":"bib12","series-title":"Internal Medicine","first-page":"584","article-title":"Thyroid anaplastic carcinoma producing granulocyte-colony-stimulating factor and parathyroid hormone-related protein","volume":"34","author":"Yazawa","year":"1995","unstructured":"Yazawa SToshimori HNakatsuru KKatakami HTakemura J & Matsukura S. Thyroid anaplastic carcinoma producing granulocyte-colony-stimulating factor and parathyroid hormone-related protein. Internal Medicine199534584\u2013588. (https:\/\/doi.org\/10.2169\/internalmedicine.34.584)"},{"key":"bib13","series-title":"Journal of Clinical Endocrinology and Metabolism","first-page":"2653","article-title":"Hypercalcemia caused by ectopic production of parathyroid hormone in a patient with papillary adenocarcinoma of the thyroid gland","volume":"83","author":"Iguchi","year":"1998","unstructured":"Iguchi HMiyagi CTomita KKawauchi SNozuka YTsuneyoshi M & Wakasugi H. Hypercalcemia caused by ectopic production of parathyroid hormone in a patient with papillary adenocarcinoma of the thyroid gland. Journal of Clinical Endocrinology and Metabolism1998832653\u20132657. (https:\/\/doi.org\/10.1210\/jcem.83.8.5025)"},{"key":"bib14","series-title":"Gan No Rinsho","first-page":"55","article-title":"A case report of thyroid papillary cancer that manifested leukocytosis and hypercalcemia after radiotherapy in bone metastasis","volume":"35","author":"Kobayashi","year":"1989","unstructured":"Kobayashi HEndo KNishimura KKasagi KYamamoto IKonishi JAbe M & Shimizu Y. A case report of thyroid papillary cancer that manifested leukocytosis and hypercalcemia after radiotherapy in bone metastasis. Gan No Rinsho19893555\u201362."},{"key":"bib15","series-title":"Advanced Biomedical Research","first-page":"92","article-title":"A case of functional metastatic follicular thyroid carcinoma that presented with hip fracture and hypercalcemia","volume":"7","author":"Karimifar","year":"2018","unstructured":"Karimifar M. A case of functional metastatic follicular thyroid carcinoma that presented with hip fracture and hypercalcemia. Advanced Biomedical Research2018792. (https:\/\/doi.org\/10.4103\/abr.abr_160_17)"},{"key":"bib16","series-title":"AACE Clinical Case Reports","first-page":"e204","article-title":"Metastatic H\u00fcrthle cell carcinoma presenting with low free thyroxine, severe hypercalcemia and spurious growth hormone production","volume":"5","author":"Rehman","year":"2019","unstructured":"Rehman S & Dhatariya KK. Metastatic H\u00fcrthle cell carcinoma presenting with low free thyroxine, severe hypercalcemia and spurious growth hormone production. AACE Clinical Case Reports20195e204\u2013e209. 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