par Costante, Giuseppe ;Lalami, Yassine ;Jungels, Christiane;Awada, Ahmad
Editeur scientifique Giovanella, Luca
Référence Atlas of Thyroid and Neuroendocrine Tumor Markers, Springer, Cham, page (133-150)
Publication Publié, 2018
Partie d'ouvrage collectif
Résumé : The neoplastic proliferation of parafollicular thyroid cells (C cells), generically defined as C cell disease, may occur as either medullary thyroid carcinoma (MTC) or C cell hyperplasia (CCH).The preoperative diagnosis of C cell disease is difficult. CCH, in fact, can only be recognized at surgical pathology. MTC, typically presenting as a thyroid nodule, may often be overlooked by traditional fine needle aspiration cytology (FNAC).Because neoplastic C cells maintain calcitonin (CT) expression, the hormone constitutes a very sensitive pre- and postoperative marker of C cell disease, with high prognostic value.MTC patients also present increased serum CEA levels. At variance with circulating CT, however, serum CEA displays a poor preoperative sensitivity for MTC diagnosis and a more limited efficacy as a prognostic factor.In the preoperative settings, in fact, circulating CT is the most specific and sensitive disease marker for MTC, while CEA displays a lower diagnostic accuracy, and both are of prognostic utility, allowing accurate estimation of tumor burden.During the postsurgical follow-up of MTC patients, the evolution of both CT and CEA levels allows a good estimate of MTC progression, and their increase reliably heralds persistence/relapse. Nevertheless, some patients may present discrepant results with disproportionately low circulating CT as compared to CEA levels. In such instance, the clinician should be alerted and consider the possibility of dedifferentiated, more aggressive MTC.In recent years, CT and CEA doubling times (DT) have been proposed as prognostic factors, being CT-DT a more precise indicator of MTC progression than CEA-DT.Circulating CT and CEA levels represent also accurate markers of response to local treatment in early and advanced/recurrent MTC, but their suitability for the evaluation of response to systemic therapy needs confirmation.