Neuroendocrine lesions of the thyroid are rare. The most common types are medullary thyroid carcinomas (MTCs) and C-cell hyperplasia. MTCs originate from thyroid parafollicular cells that secrete calcitonin which serves as a serum marker of MTCs. Here, the rare case of a calcitonin-negative neuroendocrine tumor (NET) derived from follicular lesions of the thyroid is described. A 34-year-old man presented at our hospital for the surgical management of an incidental thyroid nodule that was observed on an ultrasound sonography (USG) of the neck. Initially, USG-guided aspiration cytology was performed, and a MTC was suspected. The expressions of thyroglobulin and thyroid transcription factor-1, which are thyroid follicular cell markers, and synaptophysin and chromogranin A, which are neuroendocrine markers, was confirmed following surgical pathology. However, the staining of calcitonin, a marker of MTCs, was not observed. A nonmedullary NET of the thyroid is uncommon, and the distinction between calcitonin-negative NETs and MTCs of the thyroid may be important due to differences in their clinical courses and management.

Citations

Citations to this article as recorded by  

• Calcitonin-Negative Neuroendocrine Carcinoma of the Thyroid Gland: Case Report and Literature Review
  Ricardo Fernández-Ferreira, Ildefonso Roberto De la Peña-López, Karla Walkiria Zamudio-Coronado, Luis Antonio Delgado-Soler, María Eugenia Torres-Pérez, Christianne Bourlón-de los Ríos, Rubén Cortés-González
  Case Reports in Oncology.2021; 14(1): 112.     CrossRef
• Calcitonin-negative neuroendocrine tumor of the thyroid with metastasis to liver-rare presentation of an unusual tumor: A case report and review of literature
  Huai-Jie Cai, Han Wang, Nan Cao, Bin Huang, Fan-Lei Kong, Li-Ren Lu, Ya-Yuan Huang, Wei Wang
  World Journal of Clinical Cases.2020; 8(1): 179.     CrossRef
• Medullary thyroid carcinoma with double negative calcitonin and CEA: a case report and update of literature review
  Claudio Gambardella, Chiara Offi, Guglielmo Clarizia, Roberto Maria Romano, Immacolata Cozzolino, Marco Montella, Rosa Maria Di Crescenzo, Massimo Mascolo, Angelo Cangiano, Sergio Di Martino, Giancarlo Candela, Giovanni Docimo
  BMC Endocrine Disorders.2019;[Epub]     CrossRef
• Calcitonin negative Medullary Thyroid Carcinoma: a challenging diagnosis or a medical dilemma?
  Claudio Gambardella, Chiara Offi, Renato Patrone, Guglielmo Clarizia, Claudio Mauriello, Ernesto Tartaglia, Francesco Di Capua, Sergio Di Martino, Roberto Maria Romano, Lorenzo Fiore, Alessandra Conzo, Giovanni Conzo, Giovanni Docimo
  BMC Endocrine Disorders.2019;[Epub]     CrossRef
• Calcitonin-Negative Neuroendocrine Tumor of the Thyroid
  Megan Parmer, Stacey Milan, Alireza Torabi
  International Journal of Surgical Pathology.2017; 25(2): 191.     CrossRef
• Clinical and pathological analysis of 19 cases of medullary thyroid carcinoma without an increase in calcitonin
  Qiufeng Zhou, Shuanglei Yue, Ye Cheng, Ju Jin, Haimiao Xu
  Experimental and Toxicologic Pathology.2017; 69(8): 575.     CrossRef
• Primary Calcitonin-negative Neuroendocrine Tumor
  Sabri Özden, Aysel Colak, Baris Saylam, Ömer Cengiz
  World Journal of Endocrine Surgery.2017; 9(3): 104.     CrossRef
• LONG-TERM RESULTS OF SURGICAL TREATMENT OF PATIENTS WITH FOLLICULAR TUMORS OF THE THYROID
  I. N. Zubarovskiy, M. V. Mikhailova, S. K. Osipenko
  Grekov's Bulletin of Surgery.2015; 174(5): 32.     CrossRef